Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2019

Earnings Per Share [Abstract]

Calculation of Historical Outstanding Dilutive Securities Not Included in Diluted Loss per Share

Potentially dilutive securities excluded from the diluted loss per share calculation are as follows:

	March 31,
	2019	2018
Outstanding options to purchase common stock	11,840,521	9,640,452
Outstanding warrants to purchase common stock	243,115	100,602
Total potentially dilutive shares excluded from loss per share	12,083,636	9,741,054