v3.26.1
Stock-Based Compensation (Tables)
6 Months Ended
Jun. 30, 2026
Share-Based Payment Arrangement [Abstract]  
Summary of Stock Option Activity

The following table summarizes stock option activity for the six months ended June 30, 2026 (in thousands, except share and per share amounts):

 

Number of Options

 

 

Weighted Average
Exercise Price

 

 

Weighted Average
Remaining Contractual
Term (Years)

 

 

Aggregate
Intrinsic Value

 

Outstanding at January 1, 2026

 

12,468,296

 

 

$

3.99

 

 

 

7.8

 

 

$

595

 

Granted(1)

 

3,711,138

 

 

 

1.50

 

 

 

 

 

 

 

Exercised

 

(28,706

)

 

 

1.64

 

 

 

 

 

 

 

Expired

 

(1,093

)

 

 

1.97

 

 

 

 

 

 

 

Forfeited

 

(347,835

)

 

 

2.21

 

 

 

 

 

 

 

Outstanding at June 30, 2026

 

15,801,800

 

 

$

3.45

 

 

 

6.8

 

 

$

17,918

 

Options exercisable June 30, 2026

 

10,353,420

 

 

$

4.39

 

 

 

5.4

 

 

$

10,140

 

 

(1) Includes 250,956 performance stock options granted during the six months ended June 30, 2026, which vest only upon closing of qualified financing. As of June 30, 2026, the performance stock options are not fully vested.

Schedule of Estimated Fair Value Assumptions

The weighted-average grant-date fair value of options granted during the three months ended June 30, 2026 and 2025 was $1.82 and $0.78 per share respectively, and the six months ended was $1.06 and $0.78 per share respectively, and was calculated using the following key input assumptions in the Black-Scholes option-pricing model:

 

 

Three Months Ended June 30,

 

Six Months Ended June 30,

2026

 

2025

 

2026

 

2025

Expected volatility

99.68%

 

99.43% - 101.51%

 

98.78% - 103.00%

 

93.92% - 101.51%

Risk-free interest rate

4.13%

 

3.75% - 4.11%

 

3.86% - 4.13%

 

3.75% - 4.45%

Expected dividend yield

0.00%

 

0.00%

 

0.00%

 

0.00%

Expected term (in years)

6.08

 

5.25 - 6.08

 

5.27 - 6.08

 

5.00 - 6.08

Summary of Restricted Stock Awards and Restricted Stock Units

The following table summarizes restricted stock units activity for the six months ended June 30, 2026:

 

 

Number of Units

 

 

Weighted Average
Grant Date Fair Value

 

Outstanding at January 1, 2026

 

1,634,519

 

 

$

2.61

 

Granted

 

143,708

 

 

 

1.38

 

Forfeited

 

(117,849

)

 

 

0.12

 

Vested and settled

 

(381,049

)

 

 

2.35

 

Outstanding at June 30, 2026(1)

 

1,279,329

 

 

$

2.78

 

 

(1) Includes 886,081 RSUs which are vested but not settled at June 30, 2026.

Summary of Total Stock-based Compensation Expense

The following table summarizes the total stock-based compensation expense for the three and six months ended June 30, 2026 and 2025, respectively (in thousands):

Three Months Ended June 30,

 

 

Six Months Ended June 30,

 

2026

 

 

2025

 

 

2026

 

 

2025

 

General and administrative

$

5,077

 

 

$

2,446

 

 

$

5,932

 

 

$

4,955

 

Research and development

 

451

 

 

 

569

 

 

 

806

 

 

 

1,691

 

Total

$

5,528

 

 

$

3,015

 

 

$

6,738

 

 

$

6,646