v3.23.2
Stock-Based Compensation (Tables)
6 Months Ended
Jun. 30, 2023
Summary of Assumptions Used in Black-Scholes Option Pricing Model

Three Months Ended

Six Months Ended

June 30, 

June 30, 

    

2023

    

2022

    

    

2023

    

2022

    

Risk-free interest rate

 

3.38% - 3.89%

2.83% - 3.54%

 

3.38% - 4.22%

1.70% - 3.54%

 

Expected volatility

 

80.3% - 81.3%

77.8% - 81.5%

 

76.3% - 81.3%

77.8% - 81.9%

 

Expected dividend yield

 

0%

0%

 

0%

0%

 

Expected life of employee and Board options (in years)

 

6.25

6.25

 

 

6.25

6.25

 

Summary of Compensation Expense Relating to Stock Options

Three Months Ended

Six Months Ended

June 30, 

June 30, 

    

2023

    

2022

    

2023

    

2022

    

Research and development

$

1,447

$

1,744

$

2,927

$

3,661

General and administrative

 

1,434

 

1,958

 

2,675

 

3,988

Total stock option expense

$

2,881

$

3,702

$

5,602

$

7,649

Summary of Stock Option Activity

Weighted

Number of

Average Exercise

    

Shares

    

 Price

    

Outstanding, December 31, 2022

 

7,689,449

$

14.35

 

Granted

 

1,798,921

 

8.76

 

Exercised

 

(93,218)

 

6.00

 

Forfeited

 

(117,629)

 

11.27

 

Expired

 

(1,142,926)

 

14.35

 

Outstanding, June 30, 2023

 

8,134,597

$

13.25

Options exercisable, June 30, 2023

 

4,388,343

Employees And Non-Employee Members Of Board Of Directors [Member]  
Summary of Restricted Stock Unit Activity

Weighted

Number of

Average Grant

    

Units

    

Date Fair Value

Outstanding, December 31, 2022

 

372,513

$

13.20

Awarded

 

601,172

 

7.81

Vested and released

 

(178,247)

 

12.15

Forfeited

 

(3,585)

 

10.46

Outstanding, June 30, 2023

 

791,853

$

9.36

Restricted stock units exercisable (vested and deferred), June 30, 2023