v3.26.1
Stock-Based Compensation (Tables)
12 Months Ended
Dec. 31, 2025
Share-Based Payment Arrangement [Abstract]  
Summary of Stock Options Activity Under 2021 Long-Term Performance Incentive Plan ("2021 LTPIP"), 2018 Plan and 2015 Plan

Stock option activity, including stock options and performance-based stock options under the 2021 LTPIP, 2018 Plan and 2015 Plan is summarized as follows:

 

 

 

Number
of
Options

 

 

Weighted
Average
Exercise
Price

 

 

Weighted
Average
Remaining
Contractual
Term
(in years)

 

 

Aggregate
Intrinsic
Value
(in thousands)

 

Outstanding at December 31, 2024

 

 

19,873,073

 

 

$

36.06

 

 

 

6.88

 

 

$

51,018

 

Granted

 

 

3,784,474

 

 

 

4.36

 

 

 

 

 

 

 

Exercised

 

 

(925,813

)

 

 

5.79

 

 

 

 

 

 

 

Forfeited or canceled

 

 

(508,498

)

 

 

14.60

 

 

 

 

 

 

 

Outstanding at December 31, 2025

 

 

22,223,236

 

 

$

32.42

 

 

 

6.43

 

 

 

328,282

 

Options exercisable as of December 31, 2025

 

 

12,741,012

 

 

$

30.46

 

 

 

5.46

 

 

$

185,993

 

Fair Value of Employee Stock Options Estimated Using Weighted-average Assumptions

The Company estimated the fair value of stock options using the Black-Scholes valuation model. The fair value of time-vested stock options was estimated using the following weighted-average assumptions:

 

 

 

Year Ended December 31,

 

 

 

2025

 

 

2024

 

 

2023

 

Expected volatility

 

 

95

%

 

 

92

%

 

 

86

%

Risk-free interest rate

 

 

3.80

%

 

 

3.92

%

 

 

3.55

%

Dividend yield

 

 

0

%

 

 

0

%

 

 

0

%

Expected term

 

 

3.98

 

 

 

3.98

 

 

 

4.00

 

Summary of Restricted Shares

Restricted share activity, including restricted stock units and performance-based restricted stock units, under the 2018 Plan is summarized as follows:

 

 

Number of
Restricted
Shares

 

 

Weighted
Average
Grant Date
Fair Value

 

Unvested at December 31, 2024

 

 

121,660

 

 

$

16.08

 

Granted

 

 

55,300

 

 

 

7.92

 

Vested

 

 

(45,190

)

 

 

34.88

 

Canceled

 

 

(10,950

)

 

 

13.23

 

Unvested at December 31, 2025

 

 

120,820

 

 

$

5.58

 

Summary of Stock-based Compensation Classified in Condensed Consolidated Statements of Operations and Comprehensive Loss

Stock-based compensation is classified in the consolidated statements of operations and comprehensive loss as follows (in thousands):

 

 

 

Year Ended December 31,

 

 

 

2025

 

 

2024

 

 

2023

 

Research and development

 

$

29,503

 

 

$

24,162

 

 

$

44,014

 

General and administrative

 

 

29,360

 

 

 

36,051

 

 

 

44,542

 

Total stock-based compensation

 

$

58,863

 

 

$

60,213

 

 

$

88,556

 

Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award [Table Text Block]

The following is a summary of stock-based compensation expense by award type (in thousands):

 

 

 

Year Ended December 31,

 

 

 

2025

 

 

2024

 

 

2023

 

LTPIP Program

 

$

47,585

 

 

$

42,889

 

 

$

53,710

 

Stock options

 

 

10,155

 

 

 

14,010

 

 

 

27,472

 

RSUs

 

 

964

 

 

 

2,450

 

 

 

4,968

 

ESPP

 

 

147

 

 

 

71

 

 

 

215

 

Performance-based awards

 

 

12

 

 

 

793

 

 

 

2,191

 

Total stock-based compensation

 

$

58,863

 

 

$

60,213

 

 

$

88,556