v3.26.1
Equity Incentive Plans, Equity Inducement Plans, Employee Stock Purchase Plan and Stock-Based Compensation (Tables)
12 Months Ended
Dec. 31, 2025
Share-Based Payment Arrangement [Abstract]  
Summary of Option Activity

The following table summarizes option activity under the Company’s Equity Incentive Plans:

 

 

Shares

 

 

Weighted-
Average
Exercise Price

 

 

Weighted-
Average
Remaining
Contract Term
(Years)

 

 

Aggregate
Intrinsic Value
(in thousands)

 

Stock options outstanding
    at December 31, 2024

 

 

867,072

 

 

$

98.93

 

 

 

5.89

 

 

$

 

Granted

 

 

401,465

 

 

 

8.21

 

 

 

 

 

 

 

Exercised

 

 

(827

)

 

 

5.40

 

 

 

 

 

 

 

Canceled and forfeited

 

 

(349,901

)

 

 

109.43

 

 

 

 

 

 

 

Stock options outstanding
    at December 31, 2025

 

 

917,809

 

 

$

55.33

 

 

 

6.19

 

 

$

1,224

 

Stock options exercisable
    at December 31, 2025

 

 

544,368

 

 

$

84.37

 

 

 

4.08

 

 

$

263

 

Schedule of Employee Stock Options Valuation

For determining stock-based compensation expense, the fair-value-based measurement of each employee stock option was estimated as of the date of grant using the Black-Scholes option pricing model with assumptions as follows:

 

 

Year Ended December 31,

 

 

 

2025

 

 

2024

 

Expected term (in years)

 

2.5-6.1

 

 

6.0-6.1

 

Expected volatility

 

84.5%-94.3%

 

 

86.4%-89.2%

 

Risk-free interest rate

 

3.5%-4.2%

 

 

3.5%-4.7%

 

Expected dividend

 

 

 

 

 

 

Summary of Status and Activity of Non-vested RSUs

A summary of the status and activity of non-vested RSUs for the year ended December 31, 2025 is as follows:

 

 

Number of
Shares

 

 

Weighted
Average
Grant-Date
Fair Value

 

Non-vested December 31, 2024

 

 

595,691

 

 

$

60.54

 

Granted

 

 

359,725

 

 

 

5.70

 

Released

 

 

(252,107

)

 

 

72.17

 

Canceled

 

 

(285,537

)

 

 

36.67

 

Non-vested December 31, 2025

 

 

417,772

 

 

$

22.63

 

 

Schedule of Fair Value of ESPP Shares Using Option Pricing Model For the years ended December 31, 2025 and 2024, the fair value of ESPP shares was estimated using the following assumptions:

 

 

Year Ended December 31,

 

 

 

2025

 

 

2024

 

Expected term (in years)

 

0.5

 

 

0.5

 

Expected volatility

 

104.8%-130.3%

 

 

88.4-93.7%

 

Risk-free interest rate

 

3.8%-4.3%

 

 

4.6%-5.5%

 

Expected dividend

 

 

 

 

 

 

 

Schedule of Stock-Based Compensation Expense Recognized

Total stock-based compensation expense recognized was as follows:

 

 

Year Ended December 31,

 

 

 

2025

 

 

2024

 

 

 

(in thousands)

 

Research and development expense:

 

 

 

 

 

 

  Stock options

 

$

981

 

 

$

1,898

 

  Restricted stock units

 

 

4,406

 

 

 

9,813

 

  ESPP

 

 

(35

)

 

 

792

 

  Subtotal

 

 

5,352

 

 

 

12,503

 

General and administrative expense:

 

 

 

 

 

 

  Stock options

 

 

2,636

 

 

 

5,494

 

  Restricted stock units

 

 

3,071

 

 

 

6,517

 

  ESPP

 

 

(8

)

 

 

173

 

  Subtotal

 

 

5,699

 

 

 

12,184

 

Restructuring and related costs

 

 

2,957

 

 

 

 

Total

 

$

14,008

 

 

$

24,687