Stock-based compensation (Tables)

3 Months Ended

Mar. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of stock option activity

The following table summarizes stock option activity for employees and non-employees for the three months ended March 31, 2015:

	Shares		Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
Outstanding at December 31, 2014	926,832		$	3.40
Granted	287,743		13.19
Exercised	(37,064	)	10.79
Cancelled or forfeited	(23,350	)	10.79
Outstanding at March 31, 2015	1,154,161		$	5.46	9.50	$	16,324,513
Exercisable at March 31, 2015	13,017		$	0.61	9.04	$	247,174
Vested or expected to vest at March 31, 2015	1,084,741		$	5.37	9.50	$	15,431,131

Summary of stock-based compensation expense

Total stock-based compensation expense recognized for employee and non-employee restricted common stock, and stock options granted to employees and non-employees is included in the Company's condensed consolidated statement of operations and comprehensive loss as follows:

	Three Months Ended March 31, 2015		Period from February 26, 2014 (Inception) to March 31, 2014
Research and development	$	957,210	$	6,558
General and administrative	788,550		5,377
Total	$	1,745,760	$	11,935