Net Loss Per Share Attributable to Common Stockholders (Tables)

12 Months Ended

Dec. 31, 2014

Schedule of Basic and Diluted Net Loss Per Common Share

The following table summarizes the computation of basic and diluted net loss per share attributable to common stockholders of the Company (in thousands, except share data and per share data):

	Years Ended December 31,
	2014			2013			2012
Net loss	$	(23,342	)	$	(17,143	)	$	(22,101	)
Accretion of preferred stock issuance costs to redemption value		—			—			(73	)
Net loss attributable to common stockholders — basic and diluted	$	(23,342	)	$	(17,143	)	$	(22,174	)
Weighted-average number of common shares — basic and diluted		14,548,516			684,330			609,344
Net loss per share attributable to common stockholders — basic and diluted	$	(1.60	)	$	(25.05	)	$	(36.39	)

Potentially Dilutive Securities Excluded from Computation of Diluted Weighted-Average Shares Outstanding

The following potentially dilutive securities outstanding have been excluded from the computation of diluted weighted-average shares outstanding, because such securities had an antidilutive impact due to the losses reported (in common stock equivalent shares):

	As of December 31,
	2014		2013		2012
Options to purchase common stock		2,126,176		1,062,694		1,046,178
Warrants to purchase redeemable convertible preferred stock		—		128,663		128,663
Warrants to purchase common stock		128,663		—		—
Redeemable convertible preferred stock		—		6,826,004		6,992,694
Convertible notes payable		—		754,785		—