Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2017

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

For the periods presented, the following table sets forth the outstanding potentially dilutive securities that have been excluded from the calculation of diluted net loss per share because to do so would be anti-dilutive:

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Common stock subject to repurchase		45,000		45,000		45,000		45,000
Warrants to purchase common stock		1,970,492		118,881		2,384,026		118,881
Common stock options		2,131,624		1,275,624		2,131,624		1,275,624
Employee stock purchase plan		11,785		8,272		16,970		11,032
Total excluded securities		4,158,901		1,447,777		4,577,620		1,450,537