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Stock-based Compensation (Tables)
 12 Months Ended
Dec. 31, 2025
Share-Based Payment Arrangement [Abstract]  
Schedule of Stock-based Compensation Expense
Stock-based compensation expense is included in the consolidated statements of operations as follows (in thousands): 
 Year Ended December 31,
 202520242023
Costs of product revenue$159 $429 $354 
Research and development2,478 2,928 2,631 
Selling, general and administrative6,987 9,730 6,986 
Total$9,624 $13,087 $9,971 
The following table presents total stock-based compensation expense by security type included in the consolidated statements of operations (in thousands):
 Year Ended December 31,
 202520242023
Stock options$5,924 $6,423 $3,962 
RSUs and RSAs3,333 4,7174,447
PSUs— 247 1,649 
PBOs— $1,357 (112)
ESPP367 343 25 
Total$9,624 $13,087 $9,971 
Schedule of Assumptions Used to Estimate the Fair Value of Option Grants The following summarizes the weighted-average assumptions used to estimate the fair value of employee stock options granted:
 Year Ended December 31,
 202520242023
Expected life (years)4.65.95.8
Volatility62.3 %73.3 %66.2 %
Risk-free interest rate3.3 %3.9 %4.0 %
Expected dividend yield0.0 %0.0 %0.0 %
The following summarizes the weighted-average assumptions used to estimate the fair value of 20,000, 20,000, and 50,000 shares of stock options granted to non-employees for services during the years ended December 31, 2025, 2024, and 2023, valued at $60 thousand, $44 thousand and $0.1 million, respectively:
 Year Ended December 31,
 202520242023
Expected life (years)5.95.85.8
Volatility77.2 %74.7 %70.1 %
Risk-free interest rate4.3 %4.4 %4.7 %
Expected dividend yield0.0 %0.0 %0.0 %
Schedule of Share-based Compensation, Stock Options, Activity
The following tables summarize stock option activities:
Number
of
Shares		Weighted Average
Exercise Price
Per Share
(In Thousands)
Outstanding at December 31, 20249,128 $5.17 
Granted3,344 $3.61 
Exercised(339)$3.09 
Forfeited/Expired(3,568)$5.35 
Outstanding at December 31, 20258,565 $4.58 
Number
of
Shares		Weighted Average
Exercise Price
Per Share		Weighted Average Remaining Contractual TermAggregate Intrinsic
Value
(In Thousands)(In Years)(In Thousands)
Outstanding at December 31, 20258,565 $4.58 7.7$1,800 
Exercisable at December 31, 20253,815 $5.82 6.4$900 
Vested and expected to vest at December 31, 20258,068 $4.68 7.6$1,662 
Schedule of Share-based Compensation, RSA Activity
The following table summarizes RSA activities:
Number
of
Shares		Weighted Average
Grant Date Fair Value
Per Share
(In Thousands)
Non-vested balance at December 31, 2024234 $3.56 
Granted— $— 
Vested(234)$3.56 
Non-vested balance at December 31, 2025— $— 
Schedule of Share-based Compensation, RSU Activity
The following table summarizes RSU activities:
Number
of
Shares		Weighted Average
Grant Date Fair Value
Per Share
(In Thousands)
Non-vested balance at December 31, 20242,010 $4.16 
Granted1,484 $3.14 
Vested(766)$5.08 
Forfeited/Expired(717)$3.86 
Non-vested balance at December 31, 20252,011 $2.96 
Schedule of Share-based Compensation, Performance Shares Award Outstanding Activity
The following tables summarize PBOs activities:
Number
of
Shares		Weighted Average
Grant Date Fair Value
Per Share
(In Thousands)
Outstanding at December 31, 20241,575 $5.43 
Forfeited/Expired(1,520)$10.28 
Outstanding at December 31, 202555 $20.15 

Number
of
Shares		Weighted Average
Exercise Price
Per Share		Weighted Average
Remaining
Contractual Term		Aggregate Intrinsic
Value
(In Thousands)(In Years)(In Thousands)
Exercisable at December 31, 202555 $20.15 5.53$— 
Vested and expected to vest at December 31, 202555 $20.15 5.53$— 
Schedule of Share-Based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions The following summarizes the weighted-average assumptions used to estimate the fair value of ESPP:
 Year Ended December 31,
202520242023
Expected life (years)1.31.20.4
Volatility82.2 %89.4 %89.6 %
Risk-free interest rate3.9 %4.6 %5.3 %
Expected dividend yield0.0 %0.0 %0.0 %