Net loss per common stock (Tables)

3 Months Ended

Mar. 31, 2017

Earnings Per Share [Abstract]

Schedule of Antidilutive Securities Excluded from Computation of Basic and Diluted Net Loss Per Common Stock

The following have been excluded from the computation of basic and diluted net loss per common stock as their effect would have been antidilutive:

	THREE MONTHS ENDED MARCH 31,
	2017		2016
Outstanding stock options		2,015,389		1,255,573
Common stock warrants		—		11,363
Total		2,015,389		1,266,936