Stockholders' (Deficit) Equity (Tables)

12 Months Ended

Dec. 31, 2022

Equity [Abstract]

Summary of Option Activity under 2018 Plan, 2013 Plan and 2010 Plan

A summary of option activity under the 2018 Plan, 2013 Plan, and 2010 Plan for the year ended December 31, 2022 is as follows:

	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value (in Thousands)
Options outstanding at December 31, 2021		1,954,975		$	8.16		7.8
Granted		960,500		$	2.33
Cancelled/forfeited		(120,625	)	$	3.41
Options outstanding at December 31, 2022		2,794,850		$	6.36		7.4	$	211
Options exercisable at December 31, 2022		1,462,238		$	9.56		6.3	$	4

Summary of Stock-Based Compensation Expense

The fair value of shares vested during the years ended December 31, 2022 and 2021 was $2.2 million and $2.0 million, respectively. The amount of stock-based compensation expense recorded to research and development expenses and to general and administrative expenses is detailed in table below:

	Years Ended December 31,
	2022		2021
Stock-based compensation expense
Research and development	$	615,477	$	696,283
General and administrative		1,225,022		1,590,724
Total stock-based compensation expense	$	1,840,499	$	2,287,007

Summary of Warrants Issued

Warrants issued to SWK

	Year Ended December 31,
	2022				2021
	Number		Weighted Average Exercise Price		Number		Weighted Average Exercise Price
Outstanding at beginning of the period		—	$	—		—		—
Granted during the period		250,000		2.08		—		—
Outstanding at end of the period		250,000	$	2.08		—	$	—
Exercisable at end of the period		250,000	$	2.08		—	$	—
Weighted average remaining life	6.3 years					—