1000000
P4Y
24209000
5000000
125000000
338000
17.00
23721219
18423000
23603000
1190000
23603000
3.67
3890000
3.66
440000
3856000
2.08
125000000
0.01
2582000
245515000
1609000
2739000
30358000
12155000
161270000
2821000
-84481000
25340000
38000
236000
234544000
73274000
2659000
42878000
1253000
230526000
1503000
228847000
234544000
228847000
1679000
9939000
2515000
3409000
440000
115007000
115007000
113840000
113840000
36000000
78000000
10000000
10000000
54000000
117000000
10000000
20000000
0.50
67708000
3
110000
0.95
238000
228847000
955000
955000
5282000
0.04
0
0
0.01
0
0
0
0.01
0
0
0
0.01
0
0
0
0.01
0
5000000
0
0.01
0
0
0
0
0.01
0
25604000
309000
309000
2.09
2201000
6512000
21511000
0.01
215000
15267000
2173000
4628000
-55747000
-73354000
340000
215000
46000
3000
69322000
5229000
340000
67784000
250000
67011000
69322000
67011000
773000
1288000
2115000
575000
5835000
215000
215000
215000
102000
53000000
53000000
14011000
14011000
155000
0.95
67011000
215000
39943000
39943000
0.01
39943000
12382000
115779000
115204000
0.01
115204000
40321000
12981000
18817000
0.01
12981000
2337000
22304000
22304000
0.01
22304000
7137000
0
0
0.01
120409000
120409000
0.01
120409000
60000000
BLUE
bluebird bio, Inc.
false
Non-accelerated Filer
2013
10-Q
2013-06-30
0001293971
--12-31
Q2
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>8.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Stock-based
compensation</b></font></td>
</tr>
</table>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">On June 3,
2013, the Company’s board of directors adopted its 2013 Stock
Option and Incentive Plan (“2013 Plan”), which was
subsequently approved by its stockholders and became effective upon
the closing of the Company’s initial public offering on
June 24, 2013. The 2013 Plan replaces the 2010 Stock Option
and Grant Plan (“2010 Plan”). Any options or awards
outstanding under the Company’s previous stock option plans,
including both the 2010 Plan and the Second Amended and Restated
2002 Employee, Director and Consultant Stock Plan (“2002
Plan”), at the time of adoption of the 2013 Plan remain
outstanding and effective. As of June 30, 2013, the total
number of common shares that may be issued under all equity award
plans is 5,282 and approximately 955 remain available for future
grants.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The 2013 Plan
allows for the granting of incentive stock options, non-qualified
stock options, and restricted stock awards to the Company’s
employees, members of the board of directors, and consultants of
the Company. The Company initially reserved 955 shares of its
common stock for the issuance of awards under the 2013 Plan. The
2013 Plan provides that the number of shares reserved and available
for issuance under the 2013 Plan will automatically increase each
January 1, beginning on January 1, 2014, by four percent
of the outstanding number of shares of common stock on the
immediately preceding December 31 or such lesser number of
shares as determined by the Company’s compensation
committee.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px; FONT-SIZE: 1px">
 </p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Stock-based
compensation expense</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Stock-based
compensation by award type is as follows:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="66%"></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Stock options</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,623</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">134</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">349</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Restricted stock
awards</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">34</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">18</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">56</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">36</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,657</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">152</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,318</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">385</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Total
compensation cost recognized for all stock-based compensation
awards in the consolidated statements of operations and
comprehensive loss is as follows:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="66%"></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Research and
development</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">912</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">105</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,259</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">223</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">General and
administrative</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">745</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">47</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,059</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">162</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,657</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">152</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,318</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">385</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">As of
June 30, 2013, there was $9,939 of unrecognized compensation
expense related to unvested stock options and restricted stock
awards that is expected to be recognized over a weighted-average
period of 2.8 years.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Restricted Common
Stock</i></b></font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="76%" align="center">
<tr>
<td width="74%"></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Shares</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b><font style="WHITE-SPACE: nowrap">Weighted-average</font><br />
grant date<br />
fair value</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Unvested balance at
December 31, 2012</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">155</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.95</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Granted</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Vested</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(45</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.04</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Forfeited</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Unvested balance at June
30, 2013</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">110</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.95</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Stock
options</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The following
table summarizes the stock option activity under the
Company’s equity award plans:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="76%" align="center">
<tr>
<td width="81%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Shares</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Weighted-<br />
average<br />
exercise<br />
price<br />
per share</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Outstanding at
December 31, 2012</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,201</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2.09</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Granted</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,723</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5.65</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Exercised</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(27</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2.34</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Canceled or
forfeited</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(7</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.05</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Outstanding at
June 30, 2013</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3,890</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.67</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Exercisable at
June 30, 2013</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,190</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2.08</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Vested and expected to vest
at June 30, 2013</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3,856</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.66</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
</table>
<p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px; FONT-SIZE: 1px">
 </p>
<p style="MARGIN-TOP: 0px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">There were 11
and 27 options exercised for the three and six months ended
June 30, 2013, respectively, and 5 for each of the three and
six months ended June 30, 2012, resulting in total proceeds of
$31, $65, and $8, respectively. In accordance with Company policy,
the shares were issued from a pool of shares reserved for issuance
under the stock plans described above.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Note
receivable</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">In November
2010, the Company received a non-recourse note from its Chief
Executive Officer (“CEO”) in exchange for the purchase
of 329 shares of restricted stock. Interest accrued on the note on
an annual basis at a rate of four percent. In May 2013, prior to
the initial filing of the registration statement in connection with
the Company’s IPO, the CEO repaid the note in full plus all
accrued interest. The Company recorded stock-based compensation
expense in connection with this restricted stock award of $16 and
$31 for the three and six months ended June 30, 2013,
respectively, and $16 and $31 for the three and six months ended
June 30, 2012, respectively.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Employee Stock
Purchase Plan</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">On June 3,
2013, the Company’s board of directors adopted its 2013
Employee Stock Purchase Plan (“2013 ESPP”), which was
subsequently approved by its stockholders and became effective upon
the closing of the Company’s initial public offering on
June 24, 2013. The 2013 ESPP authorizes the initial issuance
of up to a total of 238 shares of the Company’s common stock
to participating employees. Unless otherwise determined by the
administrator of the 2013 ESPP, the first offering will begin on
January 1 of the year designated by the administrator and end
on the following June 30.</font></p>
</div>
<div>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The warrant
liability measured at fair value as of December 31, 2012 is as
follow:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="52%"></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom" nowrap="nowrap">
<p style="BORDER-BOTTOM: #000000 1px solid; WIDTH: 39pt">
<font style="FONT-FAMILY: Times New Roman" size="1"><b>Description</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Total</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Quoted prices in<br />
active markets<br />
(Level 1)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Significant other<br />
observable inputs<br />
(Level 2)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Significant<br />
unobservable inputs<br />
(Level 3)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b>December 31,
2012</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Warrant
liability</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">215</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">215</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">215</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">215</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Recently adopted
accounting pronouncements</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">In February
2013, the FASB issued guidance to provide information about the
amounts reclassified out of accumulated other comprehensive income
(“AOCI”) by component. An entity is required to
present, either on the face of the financial statements or in the
notes, significant amounts reclassified out of AOCI by the
respective line items of net income, but only if the amount
reclassified is required to be reclassified in its entirety in the
same reporting period. For amounts that are not required to be
reclassified in their entirety to net income, an entity is required
to cross-reference to other disclosures that provide additional
details about those amounts. On January 1, 2013, the Company
adopted this standard, which had no impact on its financial
position or results of operations.</font></p>
</div>
1
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>5.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Commitments and
contingencies</b></font></td>
</tr>
</table>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">On June 3,
2013, the Company entered into a new nine-year building lease for
approximately 43,600 square feet of space in Cambridge,
Massachusetts, commencing on the earlier of the substantial
completion of the build-out work or January 1, 2014. The lease
has monthly lease payments of $209 the first 12 months with annual
rent escalations thereafter and provides a rent abatement of $209
per month for the first six months. The Company has the option to
extend this lease by an additional five years. In addition, the
lease provides a contribution from the landlord towards the initial
build-out of the space of up to $6,538. The total operating lease
obligation of the non-cancelable lease term of this agreement is
$24,209. Future minimum annual lease payments as of June 30,
2013, under this non-cancelable operating lease through the end of
the lease term are as follow: $1,253 in 2014; $2,582 in 2015;
$2,659 in 2016; $2,739 in 2017; $2,821 in 2018; and $12,155 in the
aggregate thereafter. In accordance with the lease, the Company
entered into a cash-collateralized irrevocable standby letter of
credit in the amount of $1,253, naming the landlord as beneficiary.
This letter of credit is reduced to $1,044, $835, and $627 upon the
rent commencement date and the first and second anniversaries of
the rent commencement date, respectively. The Company’s
current building lease in Cambridge, Massachusetts, expires on
March 31, 2015. The Company plans to relocate to the new space
prior to its expiration.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company is
party to various agreements, principally relating to licensed
technology, that require future payments relating to milestones not
met at June 30, 2013 and December 31, 2012 or royalties
on future sales of specified products.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company
enters into standard indemnification agreements in the ordinary
course of business. Pursuant to the agreements, the Company
indemnifies, holds harmless, and agrees to reimburse the
indemnified party for losses suffered or incurred by the
indemnified party, generally the Company’s business partners
or customers, in connection with any U.S. patent or any copyright
or other intellectual property infringement claim by any third
party with respect to the Company’s products. The term of
these indemnification agreements is generally perpetual any time
after execution of the agreement. The maximum potential amount of
future payments the Company could be required to make under these
indemnification agreements is unlimited. The Company has never
incurred costs to defend lawsuits or settle claims related to these
indemnification agreements.</font></p>
</div>
<div>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The following
table summarizes the stock option activity under the
Company’s equity award plans:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="76%" align="center">
<tr>
<td width="81%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Shares</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Weighted-<br />
average<br />
exercise<br />
price<br />
per share</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Outstanding at
December 31, 2012</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,201</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2.09</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Granted</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,723</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5.65</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Exercised</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(27</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2.34</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Canceled or
forfeited</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(7</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.05</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Outstanding at
June 30, 2013</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3,890</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.67</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Exercisable at
June 30, 2013</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,190</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2.08</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Vested and expected to vest
at June 30, 2013</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3,856</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.66</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
</table>
</div>
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>1.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Description of the
business</b></font></td>
</tr>
</table>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">bluebird bio,
Inc. (the “Company” or “bluebird bio”) was
incorporated in Delaware on April 16, 1992, and is
headquartered in Cambridge, Massachusetts. The Company was formed
to develop, manufacture and market therapies to safely and
effectively deliver genes useful in the treatment of serious human
diseases. Since its inception, the Company has devoted
substantially all of its resources to its development efforts
relating to its product candidates, including activities to
manufacture product in compliance with good manufacturing practices
(“GMP”), preparing to conduct clinical studies of its
product candidates, providing general and administrative support
for these operations and protecting its intellectual
property.</font></p>
</div>
<div>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The following
common stock equivalents were excluded from the calculation of
diluted net loss per share for the periods indicated because
including them would have had an anti-dilutive effect:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="66%"></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Preferred stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">10,041</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">10,041</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Outstanding stock
options</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3,890</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,075</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3,890</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,075</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Unvested restricted
stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">110</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">199</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">110</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">199</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">4,440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">12,755</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">4,440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">12,755</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>2.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Summary of significant
accounting policies and basis of presentation</b></font></td>
</tr>
</table>
<p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Initial public
offering</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">On
June 24, 2013, the Company completed its initial public
offering (“IPO”) whereby the Company sold 6,832 shares
of common stock (inclusive of 891 shares of common stock sold by
the Company pursuant to the full exercise of an overallotment
option granted to the underwriters in connection with the offering)
at a price of $17.00 per share. The shares began trading on the
Nasdaq Global Select Market on June 19, 2013. The aggregate
net proceeds received by the Company from the offering were
$104,921, net of underwriting discounts and commissions and
estimated offering expenses payable by the Company. Upon the
closing of the IPO, all outstanding shares of convertible preferred
stock converted into 16,389 shares of common stock; and warrants
exercisable for convertible preferred stock were automatically
converted into warrants exercisable for 338 shares of common stock,
resulting in the reclassification of the related convertible
preferred stock warrant liability of $655 to additional paid-in
capital. Additionally, the Company is now authorized to issue
125,000 shares of common stock and 5,000 shares of preferred
stock.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Basis of presentation
and principles of consolidation</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The
accompanying condensed consolidated financial statements are
unaudited and have been prepared by the Company in accordance with
accounting principles generally accepted in the United States
(“GAAP”) as found in the Accounting Standards
Codification (“ASC”) and Accounting Standards Update
(“ASU”) of the Financial Accounting Standards Board
(“FASB”). Certain information and footnote disclosures
normally included in the Company’s annual financial
statements have been condensed or omitted. These interim condensed
consolidated financial statements, in the opinion of management,
reflect all normal recurring adjustments necessary for a fair
presentation of the Company’s financial position and results
of operations for the interim periods ended June 30, 2013 and
2012.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The results of
operations for the interim periods are not necessarily indicative
of the results of operations to be expected for the full year.
These interim financial statements should be read in conjunction
with the audited financial statements as of and for the year ended
December 31, 2012, and the notes thereto, which are included
in the Company’s Prospectus that forms a part of the
Company’s Registration Statement on Form S-1 (File
No. 333-188605), which was filed with the Securities and
Exchange Commission (the “SEC”) pursuant to Rule 424 on
June 19, 2013 (the “Prospectus”).</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The
accompanying condensed consolidated financial statements include
the accounts of the Company and its wholly-owned subsidiaries,
bluebird bio France, SARL and bluebird bio Securities Corporation.
All intercompany balances and transactions have been eliminated in
consolidation. Any reference in these notes to applicable guidance
is meant to refer to GAAP. The Company views its operations and
manages its business in one operating segment. All material
long-lived assets of the Company reside in the United
States.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Reverse stock
split</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">On June 3,
2013, the board of directors and the stockholders of the Company
approved a one-for-18.967 reverse stock split of the
Company’s outstanding common stock, which was effected on
June 3, 2013. Stockholders entitled to fractional shares as a
result of the reverse stock split will receive a cash payment in
lieu of receiving fractional shares. The Company’s historical
share and per share information have been retroactively adjusted to
give effect to this reverse stock split. Shares of common stock
underlying outstanding stock options and other equity instruments
were proportionately reduced and the respective exercise prices, if
applicable, were proportionately increased in accordance with the
terms of the agreements governing such securities.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Summary of accounting
policies</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The significant
accounting policies described in the Company’s audited
financial statements as of and for the year ended December 31,
2012, and the notes thereto, which are included in the Prospectus,
have had no material changes during the six months ended
June 30, 2013, except as noted below:</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2"><i>Collaboration revenue</i></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">As of
June 30, 2013, the Company’s collaboration revenue is
generated exclusively from its collaboration arrangement with
Celgene Corporation (“Celgene”). The terms of this
arrangement contain multiple deliverables, which include at
inception: (i) discovery, research and development services,
(ii) participation on the joint steering committee and
(iii) participation on the patent committee. The collaboration
arrangement also provides Celgene with the option to obtain a
license to any product candidates resulting from the collaboration.
Moreover, Celgene has the option to extend the term of the
collaboration arrangement, first for a period of two years and then
for an additional period of one year. Additionally, the Company has
the sole right to manufacture or have manufactured supplies of
vectors and associated payloads manufactured for incorporation into
the associated product candidate in the event a product candidate
is licensed. Non-refundable payments to the Company under this
arrangement may include: (i) up-front research fees,
(ii) product candidate license fees, (iii) extension term
research fees, (iv) payments for the manufacture and supply of
vectors and payloads, (v) payments based on the achievement of
certain milestones and (vi) royalties on product sales.
Additionally, the Company may elect to share in the costs incurred
from the development, commercialization and manufacture of product
candidates licensed by its collaborators and earn its share of the
net profits or bear its share of the net losses generated from the
sale of product candidates licensed by its
collaborators.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company
analyzes multiple-element arrangements based on the guidance in
FASB ASC Topic 605-25, <i>Revenue Recognition-Multiple-Element
Arrangements</i> (“ASC 605-25”). Pursuant to the
guidance in ASC 605-25, the Company evaluates multiple-element
arrangements to determine (1) the deliverables included in the
arrangement and (2) whether the individual deliverables
represent separate units of accounting or whether they must be
accounted for as a combined unit of accounting. This evaluation
involves subjective determinations and requires management to make
judgments about the individual deliverables and whether such
deliverables are separable from the other aspects of the
contractual relationship. Deliverables are considered separate
units of accounting provided that: (i) the delivered item(s)
has value to the customer on a standalone basis and (ii) if
the arrangement includes a general right of return relative to the
delivered item(s), delivery or performance of the undelivered
item(s) is considered probable and substantially in the control of
the Company. In assessing whether an item has standalone value, the
Company considers factors such as the research, manufacturing and
commercialization capabilities of the collaboration partner and the
availability of the associated expertise in the general
marketplace. In addition, the Company considers whether the
collaboration partner can use the other deliverable(s) for their
intended purpose without the receipt of the remaining element(s),
whether the value of the deliverable is dependent on the
undelivered item(s) and whether there are other vendors that can
provide the undelivered element(s). The Company’s
collaboration arrangement does not contain a general right of
return relative to the delivered item(s).</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Arrangement
consideration that is fixed or determinable is allocated among the
separate units of accounting using the relative selling price
method. Then, the applicable revenue recognition criteria in ASC
605-25 are applied to each of the separate units of accounting in
determining the appropriate period and pattern of recognition. The
Company determines the selling price of a unit of accounting
following the hierarchy of evidence prescribed by ASC 605-25.
Accordingly, the Company determines the estimated selling price for
units of accounting within each arrangement using vendor-specific
objective evidence (“VSOE”) of selling price, if
available, third-party evidence (“TPE”) of selling
price if VSOE is not available, or best estimate of selling price
(“BESP”) if neither VSOE nor TPE is available. The
Company typically uses BESP to estimate the selling price, since it
generally does not have VSOE or TPE of selling price for its units
of accounting. Determining the BESP for a unit of accounting
requires significant judgment. In developing the BESP for a unit of
accounting, the Company considers applicable market conditions and
relevant entity-specific factors, including factors that were
contemplated in negotiating the agreement with the customer and
estimated costs. The Company validates the BESP for units of
accounting by evaluating whether changes in the key assumptions
used to determine the BESP will have a significant effect on the
allocation of arrangement consideration between multiple units of
accounting.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Options are
considered substantive if, at the inception of the arrangement, the
Company is at risk as to whether the collaboration partner will
choose to exercise the option. Factors that the Company considers
in evaluating whether an option is substantive include the overall
objective of the arrangement, the benefit the collaborator might
obtain from the arrangement without exercising the option, the cost
to exercise the option and the likelihood that the option will be
exercised. For arrangements under which an option is considered
substantive, the Company does not consider the item underlying the
option to be a deliverable at the inception of the arrangement and
the associated option fees are not included in allocable
arrangement consideration, assuming the option is not priced at a
significant and incremental discount. Conversely, for arrangements
under which an option is not considered substantive or if an option
is priced at a significant and incremental discount, the Company
would consider the item underlying the option to be a deliverable
at the inception of the arrangement and a corresponding amount
would be included in allocable arrangement consideration. All of
the options included in the Company’s collaboration
arrangement have been determined to be substantive, and none of the
options are priced at a significant and incremental
discount.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company
recognizes arrangement consideration allocated to each unit of
accounting when all of the revenue recognition criteria in ASC
605-25 are satisfied for that particular unit of accounting. The
Company will recognize as revenue arrangement consideration
attributed to licenses that have standalone value from the other
deliverables to be provided in an arrangement upon delivery. The
Company will recognize as revenue arrangement consideration
attributed to licenses that do not have standalone value from the
other deliverables to be provided in an arrangement over the
Company’s estimated performance period as the arrangement
would be accounted for as a single unit of accounting.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company
recognizes revenue from the Celgene arrangement associated with
discovery, research and development services, joint steering
committee services and patent committee services ratably over the
associated period of performance. If there is no discernible
pattern of performance and/or objectively measurable performance
measures do not exist, then the Company recognizes revenue under
the arrangement on a straight-line basis over the period the
Company is expected to complete its performance obligations.
Conversely, if the pattern of performance in which the service is
provided to the customer can be determined and objectively
measurable performance measures exist, then the Company recognizes
revenue under the arrangement using the proportional performance
method. Revenue recognized is limited to the lesser of the
cumulative amount of payments received or the cumulative amount of
revenue earned, as determined using the straight-line method or
proportional performance method, as applicable, as of the period
ending date.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">At the
inception of an arrangement that includes milestone payments, the
Company evaluates whether each milestone is substantive and at risk
to both parties on the basis of the contingent nature of the
milestone. This evaluation includes an assessment of whether:
(i) the consideration is commensurate with either the
Company’s performance to achieve the milestone or the
enhancement of the value of the delivered item(s) as a result of a
specific outcome resulting from the Company’s performance to
achieve the milestone, (ii) the consideration relates solely
to past performance and (iii) the consideration is reasonable
relative to all of the deliverables and payment terms within the
arrangement. The Company evaluates factors such as the scientific,
clinical, regulatory, commercial and other risks that must be
overcome to achieve the respective milestone and the level of
effort and investment required to achieve the respective milestone
in making this assessment. There is considerable judgment involved
in determining whether a milestone satisfies all of the criteria
required to conclude that a milestone is substantive. The Company
has concluded that all of the clinical and regulatory milestones
pursuant to its collaboration arrangement are substantive.
Accordingly, in accordance with FASB ASC Topic 605-28, <i>Revenue
Recognition-Milestone Method,</i> revenue from clinical and
regulatory milestone payments will be recognized in its entirety
upon successful accomplishment of the milestone, assuming all other
revenue recognition criteria are met. Milestones that are not
considered substantive would be recognized as revenue over the
remaining period of performance, assuming all other revenue
recognition criteria are met. Revenue from commercial milestone
payments will be accounted for as royalties and recorded as revenue
upon achievement of the milestone, assuming all other revenue
recognition criteria are met.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company
will recognize royalty revenue in the period of sale of the related
product(s), based on the underlying contract terms, provided that
the reported sales are reliably measurable and the Company has no
remaining performance obligations, assuming all other revenue
recognition criteria are met.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Use of
estimates</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The preparation
of financial statements in conformity with GAAP requires management
to make estimates and assumptions that affect the reported amounts
in the financial statements and accompanying notes. Actual results
could materially differ from those estimates. Management considers
many factors in selecting appropriate financial accounting policies
and controls, and in developing the estimates and assumptions that
are used in the preparation of these financial statements.
Management must apply significant judgment in this process. In
addition, other factors may affect estimates, including: expected
business and operational changes, sensitivity and volatility
associated with the assumptions used in developing estimates, and
whether historical trends are expected to be representative of
future trends. The estimation process often may yield a range of
potentially reasonable estimates of the ultimate future outcomes
and management must select an amount that falls within that range
of reasonable estimates. This process may result in actual results
differing materially from those estimated amounts used in the
preparation of the financial statements. Estimates are used in the
following areas, among others: stock-based compensation expense,
accrued expenses, valuation of warrants, revenue and income
taxes.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Fair value of
financial instruments</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company is
required to disclose information on all assets and liabilities
reported at fair value that enables an assessment of the inputs
used in determining the reported fair values. FASB ASC Topic 820,
<i>Fair Value Measurements and Disclosures</i>, establishes a
hierarchy of inputs used in measuring fair value that maximizes the
use of observable inputs and minimizes the use of unobservable
inputs by requiring that the observable inputs be used when
available. Observable inputs are inputs that market participants
would use in pricing the asset or liability based on market data
obtained from sources independent of the Company. Unobservable
inputs are inputs that reflect the Company’s assumptions
about the inputs that market participants would use in pricing the
asset or liability, and are developed based on the best information
available in the circumstances. The fair value hierarchy applies
only to the valuation inputs used in determining the reported fair
value of the investments and is not a measure of the investment
credit quality. The three levels of the fair value hierarchy are
described below:</font></p>
<p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">Level
1—Valuations based on unadjusted quoted prices in active
markets for identical assets or liabilities that the Company has
the ability to access at the measurement date.</font></p>
<p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">Level
2—Valuations based on quoted prices for similar assets or
liabilities in markets that are not active or for which all
significant inputs are observable, either directly or
indirectly.</font></p>
<p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">Level
3—Valuations that require inputs that reflect the
Company’s own assumptions that are both significant to the
fair value measurement and unobservable. To the extent that
valuation is based on models or inputs that are less observable or
unobservable in the market, the determination of fair value
requires more judgment. Accordingly, the degree of judgment
exercised by the Company in determining fair value is greatest for
instruments categorized in Level 3. A financial
instrument’s level within the fair value hierarchy is based
on the lowest level of any input that is significant to the fair
value measurement.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Items measured
at fair value on a recurring basis include the warrant liability
(Note 4). The carrying amounts of accounts payable and accrued
expenses approximate their fair values due to their short-term
maturities.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Recently adopted
accounting pronouncements</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">In February
2013, the FASB issued guidance to provide information about the
amounts reclassified out of accumulated other comprehensive income
(“AOCI”) by component. An entity is required to
present, either on the face of the financial statements or in the
notes, significant amounts reclassified out of AOCI by the
respective line items of net income, but only if the amount
reclassified is required to be reclassified in its entirety in the
same reporting period. For amounts that are not required to be
reclassified in their entirety to net income, an entity is required
to cross-reference to other disclosures that provide additional
details about those amounts. On January 1, 2013, the Company
adopted this standard, which had no impact on its financial
position or results of operations.</font></p>
</div>
<div>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Restricted Common
Stock</i></b></font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="76%" align="center">
<tr>
<td width="74%"></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Shares</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b><font style="WHITE-SPACE: nowrap">Weighted-average</font><br />
grant date<br />
fair value</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Unvested balance at
December 31, 2012</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">155</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.95</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Granted</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Vested</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(45</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.04</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Forfeited</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Unvested balance at June
30, 2013</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">110</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.95</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
1244000
<div>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The following
table reconciles net loss to net loss applicable to common
stockholders:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="66%"></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Numerator:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Net loss</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(4,583</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(4,563</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(11,127</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(9,631</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Accretion and dividends on
convertible preferred stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(1,285</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(2,570</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Net loss applicable to
common stockholders</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(4,583</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(5,848</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(11,127</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(12,201</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Denominator:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Weighted-average common
shares outstanding—basic and diluted</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,151</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">252</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,244</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">237</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Net loss per share
applicable to common stockholders—basic and
diluted</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(2.13</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(23.21</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(8.94</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(51.48</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
5.65
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>6.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Convertible preferred
stock</b></font></td>
</tr>
</table>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Upon the
closing of the IPO on June 24, 2013, all of the outstanding
shares of the Company’s convertible preferred stock were
converted into 16,389 shares of its common stock. As of
June 30, 2013, the Company does not have any convertible
preferred stock issued or outstanding.</font></p>
</div>
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>3.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Cash and cash
equivalents</b></font></td>
</tr>
</table>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company
considers all highly liquid securities with original final
maturities of three months or less from the date of purchase to be
cash equivalents. As of June 30, 2013 and December 31,
2012, cash and cash equivalents were comprised of funds in cash and
money market accounts. The following table presents the cash and
cash equivalents carried at fair value:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="50%"></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom" nowrap="nowrap">
<p style="BORDER-BOTTOM: #000000 1px solid; WIDTH: 39pt">
<font style="FONT-FAMILY: Times New Roman" size="1"><b>Description</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Total</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Quoted prices in<br />
active markets<br />
(Level 1)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Significant other<br />
observable inputs<br />
(Level 2)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Significant<br />
unobservable inputs<br />
(Level 3)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b>June 30,
2013</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash held in
banks</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">113,840</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">113,840</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">115,007</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">115,007</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash and cash
equivalents</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">228,847</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">228,847</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr>
<td height="8"></td>
<td height="8" colspan="4"></td>
<td height="8" colspan="4"></td>
<td height="8" colspan="4"></td>
<td height="8" colspan="4"></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b>December 31,
2012</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash held in
banks</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">14,011</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">14,011</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">53,000</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">53,000</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash and cash
equivalents</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">67,011</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">67,011</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—</font></td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Stock-based
compensation expense</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Stock-based
compensation by award type is as follows:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="66%"></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Stock options</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,623</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">134</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">349</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Restricted stock
awards</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">34</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">18</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">56</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">36</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,657</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">152</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,318</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">385</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
57765000
-8.94
2.34
1723000
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>11.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Subsequent
events</b></font></td>
</tr>
</table>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company has
evaluated all events or transactions that occurred after
June 30, 2013. In the judgment of management, there were no
material events that impacted the unaudited condensed consolidated
financial statements or disclosures.</font></p>
</div>
P2Y9M18D
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>9.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Income
taxes</b></font></td>
</tr>
</table>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Deferred tax
assets and deferred tax liabilities are recognized based on
temporary differences between the financial reporting and tax basis
of assets and liabilities using statutory rates. A valuation
allowance is recorded against deferred tax assets if it is more
likely than not that some or all of the deferred tax assets will
not be realized. There were no significant income tax provisions or
benefits for the three or six months ended June 30, 2013 and
2012. Due to the uncertainty surrounding the realization of the
favorable tax attributes in future tax returns, the Company has
recorded a full valuation allowance against the Company’s
otherwise recognizable net deferred tax assets.</font></p>
</div>
7000
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>10.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Net loss per
share</b></font></td>
</tr>
</table>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The following
table reconciles net loss to net loss applicable to common
stockholders:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="66%"></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Numerator:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Net loss</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(4,583</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(4,563</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(11,127</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(9,631</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Accretion and dividends on
convertible preferred stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(1,285</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(2,570</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Net loss applicable to
common stockholders</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(4,583</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(5,848</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(11,127</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(12,201</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Denominator:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Weighted-average common
shares outstanding—basic and diluted</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,151</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">252</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,244</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">237</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Net loss per share
applicable to common stockholders—basic and
diluted</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(2.13</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(23.21</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(8.94</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(51.48</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Basic and
diluted net loss per common share is calculated by dividing net
loss by the weighted-average number of common shares outstanding
during the period, without consideration of common stock
equivalents. The Company’s potentially dilutive shares, which
includes preferred stock in the periods in which it was
outstanding, warrants to purchase common stock, outstanding stock
options and unvested restricted stock are considered to be common
stock equivalents and are only included in the calculation of
diluted net loss per share when their effect is dilutive. The
following common stock equivalents were excluded from the
calculation of diluted net loss per share for the periods indicated
because including them would have had an anti-dilutive
effect:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="66%"></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Preferred stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">10,041</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">10,041</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Outstanding stock
options</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3,890</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,075</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3,890</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,075</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Unvested restricted
stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">110</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">199</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">110</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">199</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">4,440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">12,755</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">4,440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">12,755</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
27000
3.05
4440000
<div>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Total
compensation cost recognized for all stock-based compensation
awards in the consolidated statements of operations and
comprehensive loss is as follows:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="66%"></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Research and
development</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">912</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">105</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,259</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">223</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">General and
administrative</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">745</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">47</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,059</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">162</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,657</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">152</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,318</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">385</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Use of
estimates</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The preparation
of financial statements in conformity with GAAP requires management
to make estimates and assumptions that affect the reported amounts
in the financial statements and accompanying notes. Actual results
could materially differ from those estimates. Management considers
many factors in selecting appropriate financial accounting policies
and controls, and in developing the estimates and assumptions that
are used in the preparation of these financial statements.
Management must apply significant judgment in this process. In
addition, other factors may affect estimates, including: expected
business and operational changes, sensitivity and volatility
associated with the assumptions used in developing estimates, and
whether historical trends are expected to be representative of
future trends. The estimation process often may yield a range of
potentially reasonable estimates of the ultimate future outcomes
and management must select an amount that falls within that range
of reasonable estimates. This process may result in actual results
differing materially from those estimated amounts used in the
preparation of the financial statements. Estimates are used in the
following areas, among others: stock-based compensation expense,
accrued expenses, valuation of warrants, revenue and income
taxes.</font></p>
</div>
<div>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Fair value of
financial instruments</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company is
required to disclose information on all assets and liabilities
reported at fair value that enables an assessment of the inputs
used in determining the reported fair values. FASB ASC Topic 820,
<i>Fair Value Measurements and Disclosures</i>, establishes a
hierarchy of inputs used in measuring fair value that maximizes the
use of observable inputs and minimizes the use of unobservable
inputs by requiring that the observable inputs be used when
available. Observable inputs are inputs that market participants
would use in pricing the asset or liability based on market data
obtained from sources independent of the Company. Unobservable
inputs are inputs that reflect the Company’s assumptions
about the inputs that market participants would use in pricing the
asset or liability, and are developed based on the best information
available in the circumstances. The fair value hierarchy applies
only to the valuation inputs used in determining the reported fair
value of the investments and is not a measure of the investment
credit quality. The three levels of the fair value hierarchy are
described below:</font></p>
<p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">Level
1—Valuations based on unadjusted quoted prices in active
markets for identical assets or liabilities that the Company has
the ability to access at the measurement date.</font></p>
<p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">Level
2—Valuations based on quoted prices for similar assets or
liabilities in markets that are not active or for which all
significant inputs are observable, either directly or
indirectly.</font></p>
<p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">Level
3—Valuations that require inputs that reflect the
Company’s own assumptions that are both significant to the
fair value measurement and unobservable. To the extent that
valuation is based on models or inputs that are less observable or
unobservable in the market, the determination of fair value
requires more judgment. Accordingly, the degree of judgment
exercised by the Company in determining fair value is greatest for
instruments categorized in Level 3. A financial
instrument’s level within the fair value hierarchy is based
on the lowest level of any input that is significant to the fair
value measurement.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Items measured
at fair value on a recurring basis include the warrant liability
(Note 4). The carrying amounts of accounts payable and accrued
expenses approximate their fair values due to their short-term
maturities.</font></p>
</div>
<div>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The following
table presents the cash and cash equivalents carried at fair
value:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="50%"></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom" nowrap="nowrap">
<p style="BORDER-BOTTOM: #000000 1px solid; WIDTH: 39pt">
<font style="FONT-FAMILY: Times New Roman" size="1"><b>Description</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Total</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Quoted prices in<br />
active markets<br />
(Level 1)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Significant other<br />
observable inputs<br />
(Level 2)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Significant<br />
unobservable inputs<br />
(Level 3)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b>June 30,
2013</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash held in
banks</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">113,840</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">113,840</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">115,007</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">115,007</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash and cash
equivalents</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">228,847</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">228,847</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr>
<td height="8"></td>
<td height="8" colspan="4"></td>
<td height="8" colspan="4"></td>
<td height="8" colspan="4"></td>
<td height="8" colspan="4"></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b>December 31,
2012</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash held in
banks</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">14,011</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">14,011</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">53,000</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">53,000</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash and cash
equivalents</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">67,011</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">67,011</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2"><i>Collaboration revenue</i></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">As of
June 30, 2013, the Company’s collaboration revenue is
generated exclusively from its collaboration arrangement with
Celgene Corporation (“Celgene”). The terms of this
arrangement contain multiple deliverables, which include at
inception: (i) discovery, research and development services,
(ii) participation on the joint steering committee and
(iii) participation on the patent committee. The collaboration
arrangement also provides Celgene with the option to obtain a
license to any product candidates resulting from the collaboration.
Moreover, Celgene has the option to extend the term of the
collaboration arrangement, first for a period of two years and then
for an additional period of one year. Additionally, the Company has
the sole right to manufacture or have manufactured supplies of
vectors and associated payloads manufactured for incorporation into
the associated product candidate in the event a product candidate
is licensed. Non-refundable payments to the Company under this
arrangement may include: (i) up-front research fees,
(ii) product candidate license fees, (iii) extension term
research fees, (iv) payments for the manufacture and supply of
vectors and payloads, (v) payments based on the achievement of
certain milestones and (vi) royalties on product sales.
Additionally, the Company may elect to share in the costs incurred
from the development, commercialization and manufacture of product
candidates licensed by its collaborators and earn its share of the
net profits or bear its share of the net losses generated from the
sale of product candidates licensed by its
collaborators.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company
analyzes multiple-element arrangements based on the guidance in
FASB ASC Topic 605-25, <i>Revenue Recognition-Multiple-Element
Arrangements</i> (“ASC 605-25”). Pursuant to the
guidance in ASC 605-25, the Company evaluates multiple-element
arrangements to determine (1) the deliverables included in the
arrangement and (2) whether the individual deliverables
represent separate units of accounting or whether they must be
accounted for as a combined unit of accounting. This evaluation
involves subjective determinations and requires management to make
judgments about the individual deliverables and whether such
deliverables are separable from the other aspects of the
contractual relationship. Deliverables are considered separate
units of accounting provided that: (i) the delivered item(s)
has value to the customer on a standalone basis and (ii) if
the arrangement includes a general right of return relative to the
delivered item(s), delivery or performance of the undelivered
item(s) is considered probable and substantially in the control of
the Company. In assessing whether an item has standalone value, the
Company considers factors such as the research, manufacturing and
commercialization capabilities of the collaboration partner and the
availability of the associated expertise in the general
marketplace. In addition, the Company considers whether the
collaboration partner can use the other deliverable(s) for their
intended purpose without the receipt of the remaining element(s),
whether the value of the deliverable is dependent on the
undelivered item(s) and whether there are other vendors that can
provide the undelivered element(s). The Company’s
collaboration arrangement does not contain a general right of
return relative to the delivered item(s).</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Arrangement
consideration that is fixed or determinable is allocated among the
separate units of accounting using the relative selling price
method. Then, the applicable revenue recognition criteria in ASC
605-25 are applied to each of the separate units of accounting in
determining the appropriate period and pattern of recognition. The
Company determines the selling price of a unit of accounting
following the hierarchy of evidence prescribed by ASC 605-25.
Accordingly, the Company determines the estimated selling price for
units of accounting within each arrangement using vendor-specific
objective evidence (“VSOE”) of selling price, if
available, third-party evidence (“TPE”) of selling
price if VSOE is not available, or best estimate of selling price
(“BESP”) if neither VSOE nor TPE is available. The
Company typically uses BESP to estimate the selling price, since it
generally does not have VSOE or TPE of selling price for its units
of accounting. Determining the BESP for a unit of accounting
requires significant judgment. In developing the BESP for a unit of
accounting, the Company considers applicable market conditions and
relevant entity-specific factors, including factors that were
contemplated in negotiating the agreement with the customer and
estimated costs. The Company validates the BESP for units of
accounting by evaluating whether changes in the key assumptions
used to determine the BESP will have a significant effect on the
allocation of arrangement consideration between multiple units of
accounting.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Options are
considered substantive if, at the inception of the arrangement, the
Company is at risk as to whether the collaboration partner will
choose to exercise the option. Factors that the Company considers
in evaluating whether an option is substantive include the overall
objective of the arrangement, the benefit the collaborator might
obtain from the arrangement without exercising the option, the cost
to exercise the option and the likelihood that the option will be
exercised. For arrangements under which an option is considered
substantive, the Company does not consider the item underlying the
option to be a deliverable at the inception of the arrangement and
the associated option fees are not included in allocable
arrangement consideration, assuming the option is not priced at a
significant and incremental discount. Conversely, for arrangements
under which an option is not considered substantive or if an option
is priced at a significant and incremental discount, the Company
would consider the item underlying the option to be a deliverable
at the inception of the arrangement and a corresponding amount
would be included in allocable arrangement consideration. All of
the options included in the Company’s collaboration
arrangement have been determined to be substantive, and none of the
options are priced at a significant and incremental
discount.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company
recognizes arrangement consideration allocated to each unit of
accounting when all of the revenue recognition criteria in ASC
605-25 are satisfied for that particular unit of accounting. The
Company will recognize as revenue arrangement consideration
attributed to licenses that have standalone value from the other
deliverables to be provided in an arrangement upon delivery. The
Company will recognize as revenue arrangement consideration
attributed to licenses that do not have standalone value from the
other deliverables to be provided in an arrangement over the
Company’s estimated performance period as the arrangement
would be accounted for as a single unit of accounting.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company
recognizes revenue from the Celgene arrangement associated with
discovery, research and development services, joint steering
committee services and patent committee services ratably over the
associated period of performance. If there is no discernible
pattern of performance and/or objectively measurable performance
measures do not exist, then the Company recognizes revenue under
the arrangement on a straight-line basis over the period the
Company is expected to complete its performance obligations.
Conversely, if the pattern of performance in which the service is
provided to the customer can be determined and objectively
measurable performance measures exist, then the Company recognizes
revenue under the arrangement using the proportional performance
method. Revenue recognized is limited to the lesser of the
cumulative amount of payments received or the cumulative amount of
revenue earned, as determined using the straight-line method or
proportional performance method, as applicable, as of the period
ending date.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">At the
inception of an arrangement that includes milestone payments, the
Company evaluates whether each milestone is substantive and at risk
to both parties on the basis of the contingent nature of the
milestone. This evaluation includes an assessment of whether:
(i) the consideration is commensurate with either the
Company’s performance to achieve the milestone or the
enhancement of the value of the delivered item(s) as a result of a
specific outcome resulting from the Company’s performance to
achieve the milestone, (ii) the consideration relates solely
to past performance and (iii) the consideration is reasonable
relative to all of the deliverables and payment terms within the
arrangement. The Company evaluates factors such as the scientific,
clinical, regulatory, commercial and other risks that must be
overcome to achieve the respective milestone and the level of
effort and investment required to achieve the respective milestone
in making this assessment. There is considerable judgment involved
in determining whether a milestone satisfies all of the criteria
required to conclude that a milestone is substantive. The Company
has concluded that all of the clinical and regulatory milestones
pursuant to its collaboration arrangement are substantive.
Accordingly, in accordance with FASB ASC Topic 605-28, <i>Revenue
Recognition-Milestone Method,</i> revenue from clinical and
regulatory milestone payments will be recognized in its entirety
upon successful accomplishment of the milestone, assuming all other
revenue recognition criteria are met. Milestones that are not
considered substantive would be recognized as revenue over the
remaining period of performance, assuming all other revenue
recognition criteria are met. Revenue from commercial milestone
payments will be accounted for as royalties and recorded as revenue
upon achievement of the milestone, assuming all other revenue
recognition criteria are met.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company
will recognize royalty revenue in the period of sale of the related
product(s), based on the underlying contract terms, provided that
the reported sales are reliably measurable and the Company has no
remaining performance obligations, assuming all other revenue
recognition criteria are met.</font></p>
</div>
-22000
7461000
906000
-11127000
7291000
281000
-11127000
-452000
655000
10000
-10675000
-2000
1253000
-11127000
119841000
1265000
170000
611000
440000
18136000
5605000
106589000
65000
67539000
2318000
161836000
-1416000
-2518000
106180000
12531000
65000
344000
304000
0
<div>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The warrants
outstanding consist of the following:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="76%" align="center">
<tr>
<td width="68%"></td>
<td valign="bottom" width="12%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="12%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>June 30, 2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>December 31, 2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Warrants to purchase Series
A-1 Preferred Stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5,835</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Warrants to purchase Series
B Preferred Stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">575</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Warrants to purchase Common
Stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">102</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">6,512</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Initial public
offering</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">On
June 24, 2013, the Company completed its initial public
offering (“IPO”) whereby the Company sold 6,832 shares
of common stock (inclusive of 891 shares of common stock sold by
the Company pursuant to the full exercise of an overallotment
option granted to the underwriters in connection with the offering)
at a price of $17.00 per share. The shares began trading on the
Nasdaq Global Select Market on June 19, 2013. The aggregate
net proceeds received by the Company from the offering were
$104,921, net of underwriting discounts and commissions and
estimated offering expenses payable by the Company. Upon the
closing of the IPO, all outstanding shares of convertible preferred
stock converted into 16,389 shares of common stock; and warrants
exercisable for convertible preferred stock were automatically
converted into warrants exercisable for 338 shares of common stock,
resulting in the reclassification of the related convertible
preferred stock warrant liability of $655 to additional paid-in
capital. Additionally, the Company is now authorized to issue
125,000 shares of common stock and 5,000 shares of preferred
stock.</font></p>
</div>
1259000
<div>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Reverse stock
split</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">On June 3,
2013, the board of directors and the stockholders of the Company
approved a one-for-18.967 reverse stock split of the
Company’s outstanding common stock, which was effected on
June 3, 2013. Stockholders entitled to fractional shares as a
result of the reverse stock split will receive a cash payment in
lieu of receiving fractional shares. The Company’s historical
share and per share information have been retroactively adjusted to
give effect to this reverse stock split. Shares of common stock
underlying outstanding stock options and other equity instruments
were proportionately reduced and the respective exercise prices, if
applicable, were proportionately increased in accordance with the
terms of the agreements governing such securities.</font></p>
</div>
<div>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Basis of presentation
and principles of consolidation</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The
accompanying condensed consolidated financial statements are
unaudited and have been prepared by the Company in accordance with
accounting principles generally accepted in the United States
(“GAAP”) as found in the Accounting Standards
Codification (“ASC”) and Accounting Standards Update
(“ASU”) of the Financial Accounting Standards Board
(“FASB”). Certain information and footnote disclosures
normally included in the Company’s annual financial
statements have been condensed or omitted. These interim condensed
consolidated financial statements, in the opinion of management,
reflect all normal recurring adjustments necessary for a fair
presentation of the Company’s financial position and results
of operations for the interim periods ended June 30, 2013 and
2012.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The results of
operations for the interim periods are not necessarily indicative
of the results of operations to be expected for the full year.
These interim financial statements should be read in conjunction
with the audited financial statements as of and for the year ended
December 31, 2012, and the notes thereto, which are included
in the Company’s Prospectus that forms a part of the
Company’s Registration Statement on Form S-1 (File
No. 333-188605), which was filed with the Securities and
Exchange Commission (the “SEC”) pursuant to Rule 424 on
June 19, 2013 (the “Prospectus”).</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The
accompanying condensed consolidated financial statements include
the accounts of the Company and its wholly-owned subsidiaries,
bluebird bio France, SARL and bluebird bio Securities Corporation.
All intercompany balances and transactions have been eliminated in
consolidation. Any reference in these notes to applicable guidance
is meant to refer to GAAP. The Company views its operations and
manages its business in one operating segment. All material
long-lived assets of the Company reside in the United
States.</font></p>
</div>
<div>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The fair value
of each warrant to purchase shares of the Company’s Series
A-1 Preferred Stock as of June 30, 2012 was estimated using
the Black-Scholes option pricing model with the following
weighted-average assumptions:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="76%" align="center">
<tr>
<td width="64%"></td>
<td valign="bottom" width="16%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="16%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended<br />
June 30, 2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended<br />
June 30, 2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value of underlying
instrument</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.17</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.16</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected
volatility</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">80.3</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">79.9</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected term (in
years)</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5.04</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5.17</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Risk-free interest
rate</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.8</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.9</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected dividend
yield</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
</table>
<p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px; FONT-SIZE: 1px">
 </p>
<p style="MARGIN-TOP: 0px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The fair value
of each warrant to purchase shares of the Company’s Series B
Preferred Stock was estimated using the Black-Scholes option
pricing model with the following weighted-average
assumptions:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="64%"></td>
<td valign="bottom" width="7%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="7%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="7%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="7%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013*</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013*</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value of underlying
instrument</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.32</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.40</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.95</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.48</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected
volatility</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">81.6</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">77.1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">82.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">76.6</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected term (in
years)</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5.81</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">6.79</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5.93</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">6.92</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Risk-free interest
rate</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.2</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.2</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.4</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected dividend
yield</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
</table>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="2%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2">*</font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2">Series B warrants were
re-measured to fair value and then reclassified to additional
paid-in capital on June 24, 2013.</font></td>
</tr>
</table>
</div>
-8.94
<div>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Summary of accounting
policies</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The significant
accounting policies described in the Company’s audited
financial statements as of and for the year ended December 31,
2012, and the notes thereto, which are included in the Prospectus,
have had no material changes during the six months ended
June 30, 2013, except as noted below:</font></p>
</div>
<div>
<p style="MARGIN-TOP: 0px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The following
table sets forth a summary of changes in the fair value of the
Company’s preferred stock warrant liability which represents
a recurring measurement that is classified within Level 3 of the
fair value hierarchy wherein fair value is estimated using
significant unobservable inputs:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="68%" align="center">
<tr>
<td width="81%"></td>
<td valign="bottom" width="16%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended<br />
June 30, 2013*</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Beginning
balance</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">215</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Change in fair
value</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Reclassification to
equity</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(655</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Ending balance</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="2%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2">*</font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2">These warrants were
re-measured to fair value and then reclassified to additional
paid-in capital on June 24, 2013.</font></td>
</tr>
</table>
</div>
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>7.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Significant
agreements</b></font></td>
</tr>
</table>
<!-- xbrl,body -->
<p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Celgene
Corporation</i></b></font></p>
<p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2"><i>Summary of
the Collaboration Agreement</i></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">On
March 19, 2013, the Company entered into a Master
Collaboration Agreement (the “Collaboration Agreement”)
with Celgene to discover, develop and commercialize
disease-altering gene therapies in oncology. The collaboration is
focused on applying gene therapy technology to genetically modify a
patient’s own T cells, known as chimeric antigen receptor, or
CAR, T cells, to target and destroy cancer cells. Additionally, on
March 19, 2013, the Company entered into a Platform Technology
Sublicense Agreement (the “Sublicense Agreement”) with
Celgene pursuant to which the Company obtained a sublicense to
certain intellectual property from Celgene, originating under
Celgene’s license from Baylor College of Medicine, for use in
the collaboration.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Under the terms
of the Collaboration Agreement, the Company received a $75,000
up-front, non-refundable cash payment. The Company will be
responsible for conducting discovery, research and development
activities through completion of Phase I clinical studies, if any,
during the initial term of the agreement, or three years. The
collaboration will be governed by a joint steering committee
(“JSC”) formed by an equal number of representatives
from the Company and Celgene. The JSC will, among other activities,
review the collaboration program, review and evaluate product
candidates and approve regulatory plans. In addition to the JSC,
the Collaboration Agreement provides that the Company and Celgene
will each appoint representatives to establish a patent committee,
which will be responsible for managing the intellectual property
developed and used during the collaboration.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Prior to
expiration of the initial term of the Collaboration Agreement,
Celgene has two options to extend the term, through March 19,
2019, with the payment of significant extension fees. Separately,
Celgene has an option to license an unlimited number of product
candidates resulting from the collaboration during a period
commencing upon execution of the Collaboration Agreement and
continuing through a specified period following the completion of
Phase I clinical studies for each individual product candidate. In
the event such option is exercised, the Company would grant Celgene
an exclusive worldwide license to develop and commercialize such
product candidate. Upon exercise of the option to license a product
candidate, Celgene is required to pay an option fee, which is
subject to reduction if the Company elects to co-develop and
co-promote such product candidate in the United States. For any
product candidates licensed by Celgene, the Company may be
responsible, at Celgene’s election, to continue performing
certain development activities contemplated as part of the
collaboration plan. If Celgene does not exercise its option with
respect to a product candidate prior to the expiration of the
applicable option period (each a “declined product
candidate”), then the Company has the right to develop the
product candidate outside the scope of the collaboration, subject
to a Celgene opt-in right to obtain a license to that declined
product candidate for significant additional cash consideration.
The opt-in right exists through a specified period following the
completion of a pivotal study for the specific declined product
candidate and functions in the same manner as the option to license
any other product candidates resulting from the
collaboration.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">In addition,
Celgene would be required to make certain milestone payments upon
the achievement of specified clinical, regulatory and commercial
events. For each product candidate that is licensed by Celgene, the
Company would be eligible to receive per product up to $20,000 in
option fees, up to $10,000 in clinical milestone payments, up to
$117,000 in regulatory milestone payments and up to $78,000 in
commercial milestone payments. Clinical milestone payments are
triggered upon initiation of a defined phase of clinical research
for a product candidate. Regulatory milestone payments are
triggered upon approval to market a product candidate by the FDA or
other global regulatory authorities. Commercial milestone payments
are triggered upon the first commercial sale of an approved
pharmaceutical product and when an approved pharmaceutical product
reaches certain defined levels of net sales by the licensee or
receives approval to be marketed by certain global regulatory
authorities in a specified number of countries outside of the
United States. In addition, to the extent any of the product
candidates licensed by Celgene are commercialized, the Company
would be entitled to receive tiered royalty payments ranging from
the mid-single digits to mid-teens based on a percentage of net
sales. Royalty payments are subject to certain reductions,
including for any royalty payments required to be made by Celgene
to acquire patent rights, with an aggregate minimum floor. The
Company is not eligible to receive either milestone payments or
royalty payments unless and until Celgene exercises its option to
license a product candidate resulting from the collaboration
whereupon the parties will execute a license agreement, the terms
of which are included as part of the collaboration
arrangement.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">Additionally,
the Company may elect to co-develop and co-promote product
candidates licensed by Celgene. If the Company elects to co-develop
and co-promote a product candidate, then the parties would share
equally in all costs incurred relating to the development,
commercialization and manufacture of the product candidate within
the United States and share equally in the profits generated by
such product candidate in the United States. Additionally, if the
Company elects to co-develop and co-promote a product candidate,
then the option fees, milestones and royalties would decrease
compared to those described above. Under this scenario, the Company
would receive per product up to $10,000 in option fees, up to
$10,000 in clinical milestone payments and outside of the United
States, up to $54,000 in regulatory milestone payments and up to
$36,000 in commercial milestone payments. Clinical milestone
payments are triggered upon initiation of a defined phase of
clinical research for a product candidate. Regulatory milestone
payments are triggered upon approval to market a product candidate
by global regulatory authorities. Commercial milestone payments are
triggered when an approved pharmaceutical product reaches certain
defined levels of net sales by the licensee or receives approval to
be marketed by certain global regulatory authorities in a specified
number of countries outside the United States. In addition, to the
extent any of the product candidates licensed by Celgene and
co-developed and co-promoted by the Company are commercialized, the
Company would be entitled to receive tiered royalty payments
ranging from the mid-single digits to mid-teens based on a
percentage of net sales from sales generated outside of the United
States. Royalty payments are subject to certain reductions,
including for any royalty payments required to be made by Celgene
to acquire patent rights, with an aggregate minimum floor. The
Company is not eligible to receive profit share payments, milestone
payments or royalty payments unless and until Celgene exercises its
option to license a product candidate resulting from the
collaboration whereupon the parties will execute a co-development,
co-promote and profit share agreement, the terms of which are
included as part of the collaboration arrangement.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">In the event
Celgene elects to license a product candidate discovered and
developed as part of the Collaboration Agreement, Celgene would be
solely responsible for all costs and expenses of manufacturing and
supplying any product candidates. Subject to customary back-up
supply rights granted to Celgene, the Company has the sole right to
manufacture or have manufactured supplies of vectors and associated
payloads manufactured for incorporation into the associated product
candidate. Celgene would reimburse the Company for the costs
incurred to manufacture and supply such vectors and associated
payloads, plus a modest mark-up. The Company is not obligated to
manufacture or have manufactured supplies of vectors and associated
payloads for incorporation into an optioned product candidate
unless and until Celgene exercises its option to license a product
candidate resulting from the collaboration whereupon the parties
will execute a separate manufacturing and supply
agreement.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The
Collaboration Agreement may be terminated by either the Company or
Celgene, upon written notice, in the event of the other
party’s uncured material breach. Celgene may terminate the
Collaboration Agreement for any reason upon written notice to the
Company. If the Collaboration Agreement is terminated, rights to
product candidates in development at the time of such termination
will be allocated to the parties through a mechanism included in
the Collaboration Agreement. In addition, if Celgene terminates the
Collaboration Agreement as a result of a breach by the Company,
then any then-existing co-development and co-promotion agreement
will be automatically terminated and replaced with a license
agreement for such product candidate and any amounts payable by
Celgene under any then-existing product license agreements will be
reduced.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2"><i>Call
Option</i></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">During the
initial three-year term of the collaboration and, if extended,
during the first two-year extension term of the collaboration, in
the event that the Company engages in a change in control
transaction, including for such purposes a merger or consolidation
of the Company or the sale of all or substantially all of the
Company’s assets, or if another person or entity or group of
persons or entities acquires at least 50% of the Company’s
voting capital stock, then Celgene has the right, but not the
obligation, to terminate the Collaboration Agreement and obtain
perpetual, non-terminable, worldwide, exclusive, fully paid-up
licenses to all, but not less than all, of the product candidates
previously identified under the Collaboration Agreement (the
“Call Option”). Under the Call Option, the product
candidates to which Celgene would have the right to acquire
licenses include any product candidate previously licensed out of
the collaboration during the term of the collaboration, any product
candidate for which the Company has exercised the right to
co-develop and co-promote within the United States, any product
candidate for which Celgene previously declined its option to
obtain a license and any product candidate for which at least in
vivo efficacy studies have been initiated or authorized by the JSC.
The purchase price for such licenses would be based on the fair
value of these rights received and obligations assumed determined
pursuant to a binding arbitration process.</font></p>
<p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px; FONT-SIZE: 1px">
 </p>
<p style="MARGIN-TOP: 0px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">In addition,
during the initial three-year term of the collaboration, but not
during any extension term, in the event that Celgene exercises the
Call Option, in addition to the right to acquire the fully paid-up
licenses described above, Celgene would obtain a perpetual,
non-terminable, worldwide, exclusive license to the Company’s
intellectual property to develop one or more CAR T cell products
targeting one or more oncology associated target antigens for the
remainder of the initial collaboration term. Following the initial
collaboration term, the license to the Company’s intellectual
property is limited to target antigens identified by Celgene
promptly following the initial collaboration term for which Celgene
reasonably intends to develop CAR T cell products. There is no
limit to the number of oncology-related target antigens Celgene may
select under this license. Upon commercialization of any such
product candidate so licensed by Celgene, Celgene would be
obligated to pay the Company a specified milestone payment upon
regulatory approval and a percentage of net sales as a
royalty.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company has
concluded that the value of the Call Option is immaterial based
primarily on the probability that the Call Option would become
exercisable.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2"><i>Accounting
Analysis</i></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The
Company’s arrangement with Celgene contains the following
deliverables: (i) discovery, research and development
services, (ii) participation on the JSC and
(iii) participation on the patent committee. The Company has
determined that the options to extend the term of the agreement and
the options to license product candidates, including those related
to Celgene’s opt-in right for a declined product candidate,
are substantive options. Celgene is not contractually obligated to
exercise the options. Additionally, as a result of the uncertain
outcome of the discovery, research and development activities, the
Company is at risk with regard to whether Celgene will exercise the
options. Moreover, the Company has determined that the options are
not priced at a significant and incremental discount. Accordingly,
the options are not considered deliverables at the inception of the
arrangement and the associated option fees are not included in
allocable arrangement consideration. The Company has determined
that the potential obligation to manufacture or have manufactured
supplies of vectors and associated payloads for incorporation into
an optioned product candidate is contingent upon Celgene exercising
its option to license a product candidate resulting from the
collaboration. Therefore, consistent with the treatment of the
options to license product candidates, the Company’s
potential obligation under a manufacturing and supply agreement is
not considered a deliverable at the inception of the arrangement
and the associated fees are not included in allocable arrangement
consideration.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company has
concluded that each of the three deliverables identified at the
inception of the arrangement (discovery, research and development
services, participation on the JSC and participation on the patent
committee) has standalone value from the other undelivered
elements. Additionally, the Collaboration Agreement does not
include return rights related to the initial collaboration term.
Accordingly, each deliverable qualifies as a separate unit of
accounting.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company has
identified the allocable arrangement consideration as the $75,000
up-front payment. The Company determined that each of the
identified deliverables have the same period of performance (the
three year initial term) and have the same pattern of revenue
recognition, ratably over the period of performance. As a result,
the $75,000 arrangement consideration will be recognized over the
three year initial term.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The Company has
evaluated all of the milestones that may be received in connection
with Celgene’s option to license a product candidate
resulting from the collaboration. In evaluating if a milestone is
substantive, the Company assesses whether: (i) the
consideration is commensurate with either the Company’s
performance to achieve the milestone or the enhancement of the
value of the delivered item(s) as a result of a specific outcome
resulting from the Company’s performance to achieve the
milestone, (ii) the consideration relates solely to past
performance and (iii) the consideration is reasonable relative
to all of the deliverables and payment terms within the
arrangement. All clinical and regulatory milestones are considered
substantive on the basis of the contingent nature of the milestone,
specifically reviewing factors such as the scientific, clinical,
regulatory, commercial and other risks that must be overcome to
achieve the milestone as well as the level of effort and investment
required. Accordingly, such amounts will be recognized as revenue
in full in the period in which the associated milestone is
achieved, assuming all other revenue recognition criteria are met.
All commercial milestones will be accounted for in the same manner
as royalties and recorded as revenue upon achievement of the
milestone, assuming all other revenue recognition criteria are
met.</font></p>
<p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px; FONT-SIZE: 1px">
 </p>
<p style="MARGIN-TOP: 0px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">During the
three and six months ended June 30, 2013, the Company
recognized $6,249 and $7,291, respectively, of revenue associated
with its collaboration with Celgene related to the recognition of
discovery, research and development services. As of June 30,
2013, there is $67,708 of deferred revenue related to the
Company’s collaboration with Celgene which is classified as
current or long-term in the accompanying balance sheet based on the
contractual term of the arrangement.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Association
Française contre les Myopathies</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">In January
2011, the Company entered into a research funding agreement with
the Association Française contre les Myopathies
(“AFM”), a nonprofit organization dedicated to curing
rare neuromuscular diseases and providing treatments to reduce the
associated disabilities of such diseases. As part of the agreement,
AFM funded the Company 1,000 Euros to be used to advance the
Company’s research, process development, manufacturing,
preclinical development, and clinical development in gene therapy
for beta-hemoglobinopathies in ß-thalassemia and/or in Sickle
Cell Disease.</font></p>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The funding, or
a portion thereof depending on timing, shall be repaid to AFM upon
any of the following events: (i) upon out-licensing or sale of
the program, (ii) upon obtaining the first product
authorization for the market, or (iii) upon sale of the
Company, provided that the development is active at the time of
such sale. The agreement is for a period of four years. The Company
believes that repayment of the funds paid under the agreement is
not probable at the date of the agreement, June 30, 2013 or
December 31, 2012. The Company recognizes the revenue under
this arrangement on a straight-line basis over the term of the
agreement. The Company will reassess the probability of repayment
at the end of each reporting period.</font></p>
<p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>California Institute
for Regenerative Medicine</i></b></font></p>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">In October
2012, the California Institute for Regenerative Medicine
(“CIRM”) approved an award of approximately $9,300, to
the Company. The award was conditioned upon terms and conditions by
CIRM generally applicable to its grant recipients and the
negotiation of a grant agreement with CIRM. No amounts have been
received under this award. The Company no longer expects it will
accept the CIRM award. The Company is currently exploring other
opportunities to engage in CIRM programs.</font></p>
</div>
-11127000
<div>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="4%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>4.</b></font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2"><b>Warrants</b></font></td>
</tr>
</table>
<p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">As of
December 31, 2012, the Company had outstanding warrants to
purchase 6,512 shares of capital stock. Upon the closing of the IPO
on June 24, 2013, all of the warrants exercisable for
convertible preferred stock were automatically converted into
warrants exercisable for 338 shares of common stock. The warrants
outstanding consist of the following:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="76%" align="center">
<tr>
<td width="68%"></td>
<td valign="bottom" width="12%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="12%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>June 30, 2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>December 31, 2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Warrants to purchase Series
A-1 Preferred Stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5,835</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Warrants to purchase Series
B Preferred Stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">575</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Warrants to purchase Common
Stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">102</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">6,512</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">In conjunction
with the closing of the Company’s IPO, all warrants
exercisable for convertible preferred stock were automatically
converted into warrants exercisable for common stock, resulting in
the reclassification of the related convertible preferred stock
warrant liability to additional paid-in capital as warrants to
purchase shares of common stock are accounted for as equity
instruments. The warrant liability was re-measured to fair value
prior to reclassification to additional paid-in capital. As of
June 30, 2013, the Company had no outstanding warrant
liability. The warrant liability measured at fair value as of
December 31, 2012 is as follow:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="52%"></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom" nowrap="nowrap">
<p style="BORDER-BOTTOM: #000000 1px solid; WIDTH: 39pt">
<font style="FONT-FAMILY: Times New Roman" size="1"><b>Description</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Total</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Quoted prices in<br />
active markets<br />
(Level 1)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Significant other<br />
observable inputs<br />
(Level 2)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Significant<br />
unobservable inputs<br />
(Level 3)</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b>December 31,
2012</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 3em"><font style="FONT-FAMILY: Times New Roman" size="2">Warrant
liability</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">215</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">215</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">215</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">215</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px; FONT-SIZE: 1px">
 </p>
<p style="MARGIN-TOP: 0px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The following
table sets forth a summary of changes in the fair value of the
Company’s preferred stock warrant liability which represents
a recurring measurement that is classified within Level 3 of the
fair value hierarchy wherein fair value is estimated using
significant unobservable inputs:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="68%" align="center">
<tr>
<td width="81%"></td>
<td valign="bottom" width="16%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended<br />
June 30, 2013*</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Beginning
balance</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">215</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Change in fair
value</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">440</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Reclassification to
equity</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(655</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Ending balance</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="2%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2">*</font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2">These warrants were
re-measured to fair value and then reclassified to additional
paid-in capital on June 24, 2013.</font></td>
</tr>
</table>
<p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The fair value
of each warrant to purchase shares of the Company’s Series
A-1 Preferred Stock as of June 30, 2012 was estimated using
the Black-Scholes option pricing model with the following
weighted-average assumptions:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="76%" align="center">
<tr>
<td width="64%"></td>
<td valign="bottom" width="16%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="16%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended<br />
June 30, 2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended<br />
June 30, 2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value of underlying
instrument</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.17</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.16</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected
volatility</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">80.3</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">79.9</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected term (in
years)</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5.04</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5.17</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Risk-free interest
rate</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.8</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.9</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected dividend
yield</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
</table>
<p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px; FONT-SIZE: 1px">
 </p>
<p style="MARGIN-TOP: 0px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px">
<font style="FONT-FAMILY: Times New Roman" size="2">The fair value
of each warrant to purchase shares of the Company’s Series B
Preferred Stock was estimated using the Black-Scholes option
pricing model with the following weighted-average
assumptions:</font></p>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="92%" align="center">
<tr>
<td width="64%"></td>
<td valign="bottom" width="7%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="7%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="7%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="7%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Six months ended June 30,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013*</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013*</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: #000000 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2012</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value of underlying
instrument</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.32</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.40</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.95</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.48</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected
volatility</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">81.6</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">77.1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">82.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">76.6</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected term (in
years)</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5.81</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">6.79</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5.93</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">6.92</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Risk-free interest
rate</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.2</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.2</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.4</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="TEXT-INDENT: -1em; MARGIN-LEFT: 1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected dividend
yield</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
</table>
<p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px">
 </p>
<table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%">
<tr>
<td valign="top" width="2%" align="left"><font style="FONT-FAMILY: Times New Roman" size="2">*</font></td>
<td valign="top" align="left"><font style="FONT-FAMILY: Times New Roman" size="2">Series B warrants were
re-measured to fair value and then reclassified to additional
paid-in capital on June 24, 2013.</font></td>
</tr>
</table>
</div>
27000
P5Y11M5D
0.820
0.011
0.000
0.95
440000
655000
31000
2019-03-19
7291000
2
P2Y
P3Y
1059000
1259000
110000
3890000
440000
0
56000
2262000
0
0
0
1.04
0
45000
237000
-10185000
-51.48
12755000
14000
170000
235000
-9631000
13000
-12201000
105000
2000
-9736000
40000
-9631000
471000
170000
517000
-89000
9906000
2694000
8000
8000
-170000
385000
-7181000
-1095000
2996000
7212000
8000
2570000
133000
3507000
0
-51.48
-12201000
5000
P5Y2M1D
0.799
0.009
0.000
0.16
P6Y11M1D
0.766
0.014
0.000
0.48
31000
162000
223000
199000
2075000
440000
10041000
36000
349000
75000000
P3Y
0.04
329000
9300000
P9Y
P5Y
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0.0527
209000
1253000
209000
43600
6538000
627000
1044000
835000
655000
104921000
891000
16389000
6832000
16389000
252000
-23.21
12755000
6000
85000
-4563000
-5848000
37000
1000
-4600000
-4563000
85000
-30000
4685000
1331000
8000
152000
3354000
1285000
0
-23.21
-5848000
5000
P5Y15D
0.803
0.008
0.000
0.17
P6Y9M15D
0.771
0.012
0.000
0.40
16000
47000
105000
199000
2075000
440000
10041000
18000
134000
2151000
-2.13
4440000
3000
6334000
-4583000
6249000
-4583000
-389000
7000
-4194000
-4583000
85000
399000
10528000
3281000
31000
1657000
7247000
0
-2.13
-4583000
11000
P5Y9M22D
0.816
0.012
0.000
1.32
16000
6249000
745000
912000
110000
3890000
440000
0
34000
1623000
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These warrants were re-measured to fair value and then reclassified to additional paid-in capital on June 24, 2013.
Series B warrants were re-measured to fair value and then reclassified to additional paid-in capital on June 24, 2013.