Loss per Common Share

3 Months Ended

Mar. 31, 2018

Loss per Common Share

Loss per Common Share

4. Loss per Common Share

The following table presents the computations of basic and dilutive net loss per share:

	Three months ended March 31,
		2018		2017
Loss attributable to common shareholders — basic and diluted	$	(18,652)	$	(23,078)
Weighted-average number of common shares used in net loss per share - basic and diluted		32,903,674		29,350,268
Loss per share - basic and diluted	$	(0.57)	$	(0.79)

The following potentially dilutive securities, which represent all outstanding potentially dilutive securities, were excluded from the calculation of diluted net loss per share due to their anti-dilutive effect (in common stock equivalent shares):

	Three months ended March 31,
	2018	2017
Outstanding stock options	3,592,233	2,835,630
Warrants	2,445	2,445
Unvested restricted stock (1)	19,303	69,870
Restricted stock units	497,686	153,361
(1) - Includes shares of unvested restricted stock remaining from the early exercise of stock options.