Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2023

Stock-Based Compensation [Abstract]

Summary of Stock-Based Compensation Expense

The following table summarizes the stock-based compensation expense that was recognized in the consolidated statements of operations for the years ended December 31,

(in thousands)	2023		2022
Selling, general and administrative	$	630	$	784
Research and development		40		78
Total	$	670	$	862

Summary of Plan Stock Option Activity

The following is a summary of the Plans’ stock option activity during the years ended December 31:

	2023					2022
	Options Outstanding			Weighted Average Exercise Price		Options Outstanding			Weighted Average Exercise Price
Beginning Balance		10,485		$	404.08		7,481		$	656.05
Granted		127,353			6.38		5,833			83.96
Exercised		—			—		—			—
Forfeited/expired		(26,922	)		39.68		(2,829	)		410.34
Outstanding at December 31		110,916		$	35.90		10,485		$	404.08
Vested at December 31		8,882		$	293.89		3,531		$	727.26

Weighted Average Assumptions used in Black-Scholes Option Pricing Model

The following table provides the weighted average assumptions used in the Black-Scholes option pricing model for the years ended December 31:

	2023			2022
Expected dividend yield		0	%		0	%
Risk-free interest rate		4.16	%		2.13	%
Expected volatility		152.28	%		132.48	%
Expected life (in years)		6.19			6.15