Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2020

Equity [Abstract]

Summary of Estimated Fair Value of Stock Option Award

During the six months ended June 30, 2020, the Company granted stock options to purchase 1,172,000 shares of the Company’s common stock. Of such options, 437,500 did not begin vesting until the date that FDA approved the Gimoti NDA. The estimated fair value of each stock option award granted was determined on the date of grant using the Black Scholes option-pricing valuation model with the following weighted-average assumptions for option grants during the three and six months ended June 30, 2020 and 2019:

	Three Months Ended June 30,		Six Months Ended June 30,
	2020	2019	2020	2019
Common Stock Options
Risk free interest rate	0.39%	1.80%-2.36%	0.39%-0.96%	1.80%-2.55%
Expected option term	5.5 years	4.27-5.77 years	5.5-6.0 years	4.27-6.0 years
Expected volatility of common stock	103.99%	101.46%-112.58%	99.73%-103.99%	90.34%-112.58%
Expected dividend yield	0.0%	0.0%	0.0%	0.0%

Summary of Estimated Fair Value of Shares to be Acquired under Employee Stock Purchase Plan

The estimated fair value of the shares to be acquired under the ESPP was determined on the initiation date of each six-month purchase period using the Black-Scholes option-pricing valuation model with the following weighted-average assumptions for ESPP shares to be purchased during the six months ended June 30, 2020 and 2019:

	Six Months Ended June 30,
	2020	2019
Employee Stock Purchase Plan
Risk free interest rate	1.11%	2.52%
Expected term	0.5 years	0.5 years
Expected volatility of common stock	69.72%	130.36%
Expected dividend yield	0.0%	0.0%

Summary of Recognized Non-Cash Stock-Based Compensation Expense

The Company recognized non-cash stock-based compensation expense to employees and directors in its research and development and its general and administrative functions during the six months ended June 30, 2020 and 2019 as follows:

	Three Months Ended June 30,				Six Months Ended June 30,
	2020		2019		2020		2019
Research and development	$	134,400	$	202,117	$	254,962	$	354,291
General and administrative		228,555		142,724		418,155		369,509
Total stock-based compensation expense	$	362,955	$	344,841	$	673,117	$	723,800