Stock-based compensation (Tables)
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3 Months Ended |
Mar. 31, 2016 |
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| Schedule of stock-based compensation expense |
Total compensation cost recognized for all stock‑based compensation awards in the condensed consolidated statements of operations and comprehensive loss was as follows (in thousands):
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Three Months Ended
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March 31,
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2016
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2015
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Research and development
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$
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3,458
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$
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64
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General and administrative
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752
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1
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Total stock-compensation expense
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$
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4,210
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$
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65
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| Schedule of changes in unvested restricted stock |
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Weighted
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Average
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Grant Date
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Fair Value
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Shares
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Per Share
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Unvested Restricted Common Stock as of December 31, 2015
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1,596,853
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$
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0.0188
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Issued
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—
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—
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Vested
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(193,551)
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$
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0.0162
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Unvested Restricted Common Stock as of March 31, 2016
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1,403,302
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$
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0.0192
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| Schedule of stock option activity |
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Weighted Average
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Remaining
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Aggregate Intrinsic
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Shares
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Exercise Price
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Contractual Life
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Value (in thousands)
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Outstanding at December 31, 2015
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1,713,385
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$
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6.31
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9.6
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$
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15,580
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Granted
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695,312
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$
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18.68
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Exercised
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(8,673)
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$
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3.85
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Cancelled
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—
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—
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Outstanding at March 31, 2016
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2,400,024
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$
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9.90
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9.4
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$
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59,134
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Vested and expected to vest at March 31, 2016
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2,360,999
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$
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9.90
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9.4
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$
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58,172
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Exercisable at March 31, 2016
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113,801
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$
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4.88
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9.1
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$
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3,376
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| Employees and directors |
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| Schedule of assumptions used to value stock options |
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Three Months Ended
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March 31,
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2016
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2015
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Risk free interest rate
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1.5
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%
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1.6
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%
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Expected dividend yield
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—
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—
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Expected term (in years)
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6.25
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6.25
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Expected volatility
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80.0
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%
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83.7
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%
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| Non-employees |
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| Schedule of assumptions used to value stock options |
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Three Months Ended
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March 31,
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2016
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2015
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Risk free interest rate
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—
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1.9
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%
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Expected dividend yield
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—
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—
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Expected term (in years)
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—
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10.0
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Expected volatility
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—
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80.0
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%
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