Net Loss per Share (Tables)

12 Months Ended

Dec. 31, 2015

Net Loss per Share

Basic and diluted net loss per share attributable to common stockholders

	Year Ended
	December 31,
	2015		2014		2013
Numerator:
Net loss	$	(20,563)	$	(8,517)	$	(5,236)
Accretion of redeemable convertible preferred stock to redemption value		(2,566)		(2,054)		(1,740)
Net loss attributable to common stockholders	$	(23,129)	$	(10,571)	$	(6,976)
Denominator:
Weighted average shares of common stock outstanding		6,637,678		2,730,427		2,730,427
Less: Weighted average shares of unvested restricted common stock outstanding		(530,636)		(1,010,345)		(1,649,080)
Weighted average common shares outstanding used in calculating net loss per share attributable to common stockholders, basic and diluted		6,107,042		1,720,082		1,081,347
Net loss per share attributable to common stockholders, basic and diluted	$	(3.79)	$	(6.15)	$	(6.45)

Potential common shares excluded from the calculation of diluted net loss per share attributable to common stockholders

	Year Ended December 31,
	2015	2014	2013
Stock options to purchase common stock	1,738,524	500,262	—
Restricted stock unit awards	53,800	—	—
Unvested restricted common stock	—	759,538	1,239,247
Convertible preferred stock (as converted to common stock)	—	7,924,919	6,055,060
	1,792,324	9,184,719	7,294,307