Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2020

Stockholders' Equity

Schedule of employee service share-based compensation, allocation of recognized period costs

	Year Ended
	2020		2019
Research and development	$	583,212	$	419,801
General and administrative		789,970		616,033
	$	1,373,182	$	1,035,834

Schedule of key assumption of fair value of stock options granted

	2020		2019
Expected term	5.83 years		5.67 years
Risk-free interest rate	0.93	%	1.82	%
Expected dividend yield	—		—
Expected volatility	100.32	%	80.38	%

Schedule of stock option activity

A summary of stock option activity is as follows:

	Outstanding stock options
	Number of	Weighted average
	shares	exercise price
Balance at December 31, 2019	2,310,485	$	4.81
Options granted	1,360,000		0.92
Options exercised	—		—
Options forfeited	(51,776)		0.88
Options cancelled	(54,251)		6.32
Balance at December 31, 2020	3,564,458		3.36
Options exercisable at December 31, 2020	2,122,086		4.98

Schedule of share-based compensation of stock options outstanding and exercisable

The following table summarizes information about stock options outstanding and exercisable at December 31, 2020:

Options outstanding						Options exercisable
	Weighted						Weighted
	average						average
	remaining	Weighted					remaining	Weighted
	contractual	average					contractual	average		Aggregate
Number	life	exercise		Aggregate intrinsic		Number	life	exercise		intrinsic
outstanding	(Years)	price		value		exerciseable	(Years)	price		value
3,564,458	6.64	$	3.36	$	576,889	2,122,086	4.77	$	4.98	$	564,443

Schedule of nonvested restricted stock units activity

A summary of restricted stock unit activity is as follows:

	Number of
	unvested restricted
	stock units
Balance at December 31, 2019	661,307
Granted	—
Vested	(628,807)
Forfeited	(32,500)
Balance at December 31, 2020	—

Schedule of fair value of warrants

	December 31,			December 31,			November 18,
	2020			2019			2019
Expected life in years		3.88			4.88			5.00
Risk-free interest rate		0.27	%		1.69	%		1.63	%
Dividend yield		—			—			—
Volatility		88.46	%		225.93	%		224.47	%
Stock price	$	1.36		$	0.39		$	0.41

Schedule of reconciliation of the warrant liability

The following table is a reconciliation of the warrant liability measured at fair value using level 3 inputs:

	Warrant
	Liability
Balance at December 31, 2018	$	—
Initial fair value of common stock warrants issued in November 2019 Offering		4,827,600
Change in fair value of common stock warrants		(236,400)
Balance at December 31, 2019		4,591,200
Settlement of liabilty on warrant exercise		(6,313,338)
Change in fair value of common stock warrants		2,892,189
Balance at December 31, 2020	$	1,170,051

Schedule of number of warrants outstanding and the weighted average exercise price

The following table summarizes the number of common stock warrants outstanding and the weighted average exercise price:

		Weighted
		Average
	Common Stock	Exercise
	Warrants	Price
Outstanding at December 31, 2019	12,000,000	$	0.50
Issued	5,042,017		0.53
Exercised	(15,097,651)		0.51
Expired	—		—
Cancelled	—		—
Forfeited	—		—
Balance at December 31, 2020	1,944,366	$	0.51

Warrants outstanding
	Weighted average remaining
Number exercisable	contractual life           (Years)	Weighted average exercise price		Aggregate intrinsic value
1,944,366	4.00	$	0.51	$	1,646,945