Share-Based Payments (Tables)

9 Months Ended

Sep. 30, 2014

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

Summary of Stock Option Activity and Related Information

A summary of the Company’s stock option activity and related information follows:

	Shares			Weighted-Average Exercise Price		Remaining Contractual Life (in years)
Outstanding at December 31, 2013		1,346,238		$	3.39		8.59
Granted		205,265			14.42
Exercised		(51,507	)		0.72
Cancelled or forfeited		(7,390	)		6.74
Outstanding at September 30, 2014		1,492,606		$	4.99		8.11
Exercisable at September 30, 2014		541,315		$	2.81		7.59
Vested and expected to vest at September 30, 2014(1)		1,159,965		$	5.39		8.29

(1) Represents the number of vested options, plus the number of unvested options expected to vest.

Summary of Status and Changes of Unvested Restricted Stock

A summary of the status of unvested restricted stock is presented below:

	Restricted Stock			Weighted-Average Grant Date Fair Value
Unvested at December 31, 2013		163,353		$	0.06
Granted		73,879			11.44
Vested		(84,129	)		1.33
Unvested at September 30, 2014		153,103		$	4.86

Summary of Stock-based Compensation Expense

During the three and nine months ended September 30, 2014 and 2013, the Company recorded stock-based compensation expense for employee and non-employee stock options and restricted stock, which was allocated as follows in the statements of operations (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2014		2013		2014		2013
Research and development expense	$	449	$	307	$	948	$	715
General and administrative expense		359		19		997		40
	$	808	$	326	$	1,945	$	755