Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Assets and Liabilities Measured at Fair Value on Recurring Basis

Assets and liabilities measured at fair value on a recurring and nonrecurring basis as of December 31, 2022 and 2021 are as follows:

($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2022		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	38,058	$	38,058	$	—	$	—

($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2021		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	75,222	$	75,222	$	—	$	—

Share-Based Compensation Expense Included in Statements of Operations

The following table presents share-based compensation expense included in the Company’s Statements of Operations:

	Year Ended December 31,
(in thousands)	2022		2021
Research and development		868		2,598
General and administrative		2,660		8,176
Stock-based compensation expense	$	3,528	$	10,774

Assumptions for Volatility, Expected life, Dividend Yield and Risk-free Interest Rate

The assumptions for volatility, expected life, dividend yield and risk-free interest rate are presented in the table below:

	Year Ended December 31,
	2022	2021
Risk-free interest rate	1.63 – 4.21%	0.50 – 1.36%
Expected life in years	5.27 – 6.25	5.50 – 6.25
Expected volatility	74.49 – 88.75%	72.53 – 74.80%
Expected dividend yield	—%	—%

Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method

Basic net loss per common share is computed by dividing net loss applicable to common stockholders by the weighted average number of shares of common stock outstanding for the period. Diluted net loss per share is computed using the weighted-average number of shares of common stock outstanding during the period, plus the dilutive effect of outstanding options and warrants, using the treasury stock method and the average market price of the Company’s common stock during the applicable period, unless their effect on net loss per share is antidilutive. The effect of computing diluted net loss per common share was antidilutive for any potentially issuable shares of common stock from the conversion of stock options, unvested restricted stock and warrants and, as such, have been excluded from the calculation.

The computation of basic and diluted net loss per share consists of the following:

	Year Ended December 31,
	2022			2021
Net loss	$	(37,730	)	$	(78,751	)
Weighted-average common shares outstanding, basic and diluted		217,130,311			214,399,074
Net loss per share, basic and diluted	$	(0.17	)	$	(0.37	)

Potentially Dilutive Shares Excluded from Computation of Diluted Net Loss Per Share

Such potential common shares on December 31, 2022 and 2021 consist of the following:

	December 31,
	2022		2021
Common stock options		10,408,622		10,665,869
Inducement stock options		-		32,500
Unvested restricted stock		939,062		1,198,580
Warrants		22,922,342		22,922,342
		34,270,026		34,819,291