Net Loss Per Share Attributable to Common Stockholders (Tables)

9 Months Ended

Sep. 30, 2020

Earnings Per Share [Abstract]

Summary of Potentially Dilutive Securities Excluded from Computation of Diluted Net Loss Per Share

The following outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented, because including them would have been antidilutive:

	Nine Months Ended September 30,
	2020		2019
Redeemable convertible preferred stock (on an as-converted basis)		—		14,755,415
Options to purchase common stock		2,808,477		1,304,302
Restricted stock awards granted and not purchased		4,195		4,195
Unvested restricted shares		159,833		360,890
Total		2,972,505		16,424,802

Reconciliation of Numerator and Denominator Used in Calculation of Basic and Diluted Net Loss Per Share

A reconciliation of the numerator and denominator used in the calculation of the basic and diluted net loss per share attributable to common stockholders is as follows (in thousands, except share and per share amounts):

	Three Months Ended September 30,						Nine Months Ended September 30,
	2020			2019			2020			2019
Net loss per share:
Numerator
Net loss	$	(16,534	)	$	(13,255	)	$	(22,506	)	$	(42,800	)
Add: accretion to redemption value and cumulative    dividends on redeemable convertible preferred shares		—			(1,375	)		—			(4,078	)
Net loss attributable to common stockholders	$	(16,534	)	$	(14,630	)	$	(22,506	)	$	(46,878	)
Denominator
Weighted-average common shares outstanding used to    calculate net loss per share attributable to common    stockholders:
Basic		35,445,504			1,714,285			16,592,746			1,561,242
Diluted		35,445,504			1,714,285			16,592,746			1,561,242
Net loss per share attributable to common stockholders:
Basic	$	(0.47	)	$	(8.53	)	$	(1.36	)	$	(30.03	)
Diluted	$	(0.47	)	$	(8.53	)	$	(1.36	)	$	(30.03	)