Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation (Tables)

v2.4.0.8
Stock-based Compensation (Tables)
 9 Months Ended
Sep. 30, 2013
Stock-based Compensation [Abstract]  
Weighted average assumptions
The fair value of the stock options granted was estimated based on the following weighted average assumptions for three and nine months ended September 30, 2013 and 2012:

 
  
Three Months Ended September 30,
    
Nine Months Ended September 30,
  
 
  
2013
    
2012
    
2013
    
2012
  
Dividend yield
    
0
%
    
0
%
    
0
%
    
0
%
Expected volatility
    
92
%
    
92
%
    
92
%
    
92
%
Risk-free interest rate
    
1.43
%
    
0.72
%
    
0.87
%
    
1.05
%
Expected term
  
5.6 years
    
5.6 years
    
5.6 years
    
5.6 years
  

Stock option activity
Stock option activity for the nine months ended September 30, 2013 was as follows:

 
  
Options
    
Weighted Average Exercise Price Per Share
    
Weighted Average Remaining Contractual Life (in years)
    
Aggregate Intrinsic Value (in thousands)
  
Options outstanding at December 31, 2012
    
6,788,383
    
$
8.99
      
7.36
    
$
1,531
  
Granted
    
1,144,403
    
$
3.10
                  
Exercised
    
(297,149
)
  
$
1.75
                  
Forfeited, expired or cancelled
    
(129,296
)
  
$
17.88
                  
Options outstanding at September 30, 2013
    
7,506,341
    
$
8.23
      
7.01
    
$
8,262
  
Options exercisable at September 30, 2013
    
4,817,306
    
$
11.13
      
6.03
    
$
4,050
  

Unvested RSU activity
 Unvested RSU activity for the nine months ended September 30, 2013 is summarized below:

 
  
   
Weighted-
  
 
      
Average
 
 
  
Number of
Shares
    
Grant-Date
 Fair Value
  
Unvested balance at December 31, 2012
    
1,459,853
    
$
2.75
  
Granted
    
958,385
    
$
2.96
  
Vested
    
(419,760
)
  
$
2.99
  
Forfeited
    
(45,434
)
  
$
2.29
  
Unvested balance at September 30, 2013
    
1,953,044
    
$
2.63
  

Stock-based compensation expense
 The following table shows total stock-based compensation expense included in the condensed consolidated statements of comprehensive loss for the three and nine months ended September 30, 2013 and 2012 (in thousands):

 
  
Three Months Ended September 30,
    
Nine Months Ended September 30,
  
 
  
2013
    
2012
    
2013
    
2012
  
Research and development
  
$
474
    
$
1,304
    
$
1,904
    
$
1,984
  
Selling, general and administrative
    
753
      
818
      
2,042
      
1,384
  
Total stock-based compensation expense
  
$
1,227
    
$
2,122
    
$
3,946
    
$
3,368