Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

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

For the periods, 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:

	Year Ended December 31,
	2018		2017
Common stock subject to repurchase		18,791		45,000
Warrants to purchase common stock		2,713,561		2,744,500
Common stock options		3,017,624		2,131,624
Employee stock purchase plan		10,785		27,785
Total excluded securities		5,760,761		4,948,909

Summary of Calculation of Basic and Diluted Net Loss Per Share

The following table sets forth the calculation of basic and diluted net loss per share:

	Year Ended December 31,
	2018			2017
Net loss attributable to common shareholders for    basic net loss per share	$	(7,566,080	)	$	(12,229,512	)
Adjustment for gain from change in fair value of dilutive    warrants	—				(1,235,394	)
Net loss used for diluted net loss per share	$	(7,566,080	)	$	(13,464,906	)
Weighted-average shares used to compute basic net    loss per share		16,602,422			14,897,885
Adjustment to reflect assumed exercise of warrants	—				53,151
Weighted-average shares used to compute diluted    net loss per share		16,602,422			14,951,036
Net loss per share attributable to common shareholders:
Basic	$	(0.46	)	$	(0.82	)
Diluted	$	(0.46	)	$	(0.90	)