v3.24.3
Equity Incentive Plans (Tables)
 9 Months Ended
Sep. 30, 2024
Share-Based Payment Arrangement [Abstract]  
Schedule of Activity Related to Stock Option Awards A summary of the activity related to stock option awards during the nine months ended September 30, 2024 is as follows:
 
Shares
Subject to
Options
Weighted-Average
Exercise
Price per
Share
Weighted-Average
Remaining
Contractual
Term
(in years)
Aggregate
Intrinsic
Value (in
thousands)
Outstanding at January 1, 2024
4,225,615 $27.36 7.42$5,827 
Granted2,228,915 $21.88 
Exercised(271,210)$19.42 
Forfeitures and cancellations(225,904)$36.43 
Outstanding at September 30, 20245,957,416 $25.33 7.74$59,994 
Exercisable at September 30, 20242,648,111 $28.86 6.43$23,480 
Schedule of Time-based Restricted Stock Units Activity
Number of Restricted Stock UnitsWeighted-Average Grant Date Fair Value
Weighted-Average
Remaining
Contractual
Term
(in years)
Aggregate
Intrinsic
Value (in
thousands)
Outstanding at January 1, 20241,481,572 $24.80 0.73$31,735 
Granted811,166 $21.88 
Released(1,103,808)$25.77 
Forfeitures and cancellations(8,347)$22.16 
Outstanding at September 30, 20241,180,583 $21.91 1.65$39,550 
RSU expected to vest at September 30, 20241,180,583 $21.91 1.65$39,550 
Schedule of Weighted Average Assumptions used to Estimate Fair Value The estimated fair values of stock option awards granted were determined on the date of grant using the Black-Scholes option valuation model with the following weighted-average assumptions:
Nine Months Ended
September 30,
20242023
Risk-free interest rate4.0 %3.7 %
Expected volatility78.3 %85.9 %
Expected dividend yield— %— %
Expected term (in years)6.285.78
Weighted-average grant date fair value per share$15.59 $16.31 
Schedule of Non-cash Stock-based Compensation Expense
Total non-cash stock-based compensation expense for all stock awards that was recognized in the consolidated statements of operations and comprehensive loss is as follows:
Three Months Ended
September 30,		Nine Months Ended
September 30,
(in thousands)2024202320242023
Research and development$3,959 $2,222 $10,947 $7,675 
General and administrative4,230 5,585 
(1)
14,917 
(2)
17,419 
(3)
Total$8,189 $7,807 $25,864 $25,094 
(1)    Includes $2.9 million related to two year RSU initially issued to our Chief Executive Officer in March 2022 and now fully recognized.
(2)    Includes $2.6 million related to two year RSU initially issued to our Chief Executive Officer in March 2022 and now fully recognized.
(3)    Includes $5.8 million related to two year RSU initially issued to our Chief Executive Officer in March 2022 and now fully recognized.
Schedule of Performance Shares, Outstanding Activity
The following table presents a summary of activity with respect to our PSUs:
Number of Performance Stock UnitsWeighted-Average Grant Date Fair ValueWeighted-Average Remaining Contractual Term (in years)
Outstanding at January 1, 2024— $— —
Granted511,000 $24.69 
Released— $— 
Forfeitures— $— 
Outstanding at September 30, 2024511,000 $24.69 3.78
Schedule of Grant Date Fair Value Assumptions The grant date fair value is estimated using a Monte Carlo simulation using the following assumptions:
Nine months ended
September 30,
2024
Volatility of common stock59.0 %
Risk-free interest rate4.1 %
Contract term (in years)3.9