Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2021

Equity [Abstract]

Summary of Estimated Fair Value of Stock Option Award

During the nine months ended September 30, 2021 and 2020, the Company granted stock options to purchase 1,682,000 and 1,172,000 shares of the Company’s common stock, respectively. Of the options granted in 2020, 437,500 did not begin vesting until June 19, 2020, 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 nine months ended September 30, 2021 and 2020:

	Nine Months Ended September 30,
	2021	2020
Common Stock Options
Risk free interest rate	0.57% - 1.08%	0.39%-0.96%
Expected option term	5.5 - 6.0 years	5.5-6.0 years
Expected volatility of common stock	103.45% - 107.53%	99.73%-103.99%
Expected dividend yield	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 three and nine months ended September 30, 2021 and 2020:

	Three Months Ended September 30,		Nine Months Ended September 30,
	2021	2020	2021	2020
Employee Stock Purchase Plan
Risk free interest rate	—	0.13%	0.13%	0.13% - 1.11%
Expected term	—	0.5 years	0.5 years	0.5 years
Expected volatility of common stock	—	111.98%	111.98%	69.72% - 111.98%
Expected dividend yield	—	0.0%	0.0%	0.0%

Summary of Recognized Stock-Based Compensation Expense

The Company recognized stock-based compensation expense to employees and directors in its research and development and its selling, general and administrative functions during the three and nine months ended September 30, 2021 and 2020 as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Research and development	$	7,310	$	31,186	$	99,510	$	286,148
Selling, general and administrative		456,685		447,388		1,325,244		865,543
Total stock-based compensation expense	$	463,995	$	478,574	$	1,424,754	$	1,151,691