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Stock-Based Compensation (Tables)
 12 Months Ended
Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]  
Summary of the activity related to the shares of common stock covered by outstanding options under the plans
A summary of the activity related to the shares of common stock covered by outstanding options is as follows:
Number of SharesWeighted Average Exercise PriceRemaining Contractual Term
(in years)		Aggregate Intrinsic Value
Balance at December 31, 2021722,765 $19.22 8.79$— 
Granted260,285 3.72 
Exercised— — 
Forfeited(1,859)7.55 
Expired(1,443)712.92 
Balance at December 31, 2022979,748 14.10 8.15$— 
Granted457,600 2.16 
Exercised— — 
Forfeited(66,423)6.35 
Expired(32,004)75.42 
Balance at December 31, 20231,338,921 $8.94 7.46$— 
Vested and expected to vest at December 31, 20231,338,921 $8.94 7.46$— 
Exercisable at December 31, 2023664,919 $14.15 6.81$— 
Schedule of assumptions used in determining fair value of stock options granted using the Black-Scholes option pricing model
For the years ended December 31, 2023, and 2022, the Company determined the fair value of stock options using the Black-Scholes option-pricing model with the following assumptions for option grants, respectively:
Year Ended December 31,
20232022
Expected dividend yield——
Risk-free rate
3.5% - 4.7%
1.6% - 4.3%
Expected option term (in years)
6.2 - 6.3
6.2 - 10.0
Volatility
119% - 123%
116% - 126%
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity
A summary of RSU activity for the year ended December 31, 2023 is as follows:
Number of RSUsWeighted Average Remaining Contractual Life (years)
Outstanding at December 31, 202227,123 
Awarded— 
Released(27,123)
Forfeited— 
Outstanding at December 31, 2023— 0.00
Weighted average remaining recognition period (years)0.00