Stock-based Compensation (Tables)

9 Months Ended

Sep. 30, 2023

Share-Based Payment Arrangement [Abstract]

Schedule of Share-based Compensation Arrangements by Share-based Payment Award

The Company estimated the fair value of the Initial Loans based on assumptions used in the Monte Carlo simulation model using the following inputs as of the end of the reporting period:

	July Convertible Debenture			August Convertible Debenture			September Convertible Debenture
Expected term (in years)	0.92			1.01			1.16
Stock price	$0.49			$0.49			$0.49
Interest rate	3.0		%	3.0		%	3.0		%
Expected volatility	113.2		%	112.2		%	111.7		%
Expected dividend rate	$	—		$	—		$	—
Risk free rate	5.4		%	5.4		%	5.3		%

The following table summarizes the Company’s stock-based compensation expense by line item for the three and nine months ended September 30, 2023 and 2022 (in thousands):

	Three months ended September 30,				Nine months ended September 30,
	2023		2022		2023		2022
Research and development	$	626	$	8,217	$	4,970	$	23,342
Selling, general and administrative	6,282		11,310		18,481		37,638
Total	$	6,908	$	19,527	$	23,451	$	60,980

The fair value of the Warrants at the issuance date was measured using the Black-Scholes-Merton option pricing model. The key inputs used in the valuation were as follows:

Expected term (years)	10
Risk free interest rate	3.0	%
Expected volatility	91.3	%
Dividend yield	—	%

Exercise price	$	2.15
Stock price	$	3.63

The fair value of the warrants upon the expiration of the option period was measured using the Black-Scholes-Merton option pricing model. The key inputs used in the valuation were as follows:

Expected term (year)	0.9
Expected volatility	116.4		%
Expected dividend rate	—		%
Risk free rate	4.7		%
Estimated fair value per warrant	$	0.57
Exercise price	$	1.05
Stock price	$	1.20

The fair value of the warrants was measured using the Black-Scholes-Merton option pricing model. The key inputs used in the valuation were as follows:

Expected term (years)	4.36
Expected volatility	113.3		%
Expected dividend rate	—		%
Risk free rate	4.61		%
Estimated fair value per warrant	$	0.32
Exercise price	$	1.30
Stock price	$	0.49

The warrants are liability classified and subject to periodic remeasurement. The fair value of the warrants was measured using the Black-Scholes option pricing model. The key inputs used in the valuation were as follows:

Expected term (years)	5.23
Expected volatility	113.3	%
Expected dividend rate	—	%
Risk free rate	4.55	%
Estimated fair value per warrant	$0.39
Exercise price	$0.67
Stock price	$0.49

The warrants are liability classified and subject to periodic remeasurement. The fair value of the warrants was measured using the Black-Scholes option pricing model. The key inputs used in the valuation were as follows:

Expected term (years)	5.02
Expected volatility	124.9	%
Expected dividend rate	—	%
Risk free rate	4.55	%
Estimated fair value per warrant	$0.39
Exercise Price	$0.65
Stock Price	$0.49

The key inputs used in the valuation were as follows:

Expected term (years)	5.34
Expected volatility	113.3		%
Expected dividend rate	—		%
Risk free rate	4.55		%
Estimated fair value per warrant	$	0.39
Exercise price	$	0.67
Stock price	$	0.49

The key inputs used in the valuation were as follows:

	July Convertible Debenture			August Convertible Debenture			September Convertible Debenture
Expected term (years)	4.75			4.84			4.99
Expected volatility	113.3		%	113.3		%	113.3		%
Expected dividend rate	—		%	—		%	—		%
Risk free rate	4.57		%	4.56		%	4.55		%
Estimated fair value per warrant	$	0.39		$	0.39		$	0.40
Exercise price	$	0.54		$	0.54		$	0.54
Stock price	$	0.49		$	0.49		$	0.49