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Equity Incentive Plans and Stock-Based Compensation (Tables)
 3 Months Ended
Mar. 31, 2025
Share-Based Payment Arrangement [Abstract]  
Schedule of Black-Scholes Option Pricing Model to Estimate Stock-based Compensation Expense for Stock Option Awards
The Company used Black-Scholes option pricing model to estimate stock-based compensation expense for stock option awards with the following assumptions:
  Three Months Ended March 31,
 20252024
Expected volatility
86.82% - 86.99%
85.28% - 86.42%
Risk-free interest rate
4.11% - 4.45%
4.04% - 4.28%
Expected dividend——
Expected term (in years)
5.99 - 6.08
5.99 - 6.06
Underlying common stock fair value
$1.54 - $12.63
$15.19 - $17.44
Schedule of Option Activity Under the 2015 Plan and 2020 Plan
A summary of option activity under the 2015 Plan and the 2020 Plan is as follows:
  Number
of
Options		Weighted-
Average Exercise
Price per Share		Weighted-
Average
Remaining
Contractual
Term (in Years)		Aggregate
Intrinsic
Value
Outstanding as of December 31, 20248,300,804 $17.23 7.49$13,769 
Granted1,948,680 $11.02 
Exercised(4,921)$12.18 
Forfeited(215,984)$17.91 
Outstanding as of March 31, 202510,028,579 $16.01 7.68$— 
Exercisable as of March 31, 20255,163,216 $16.92 6.44$— 
Vested and expected to vest as of March 31, 202510,028,579 $16.01 7.68$— 
Schedule of Restricted Stock Activity
Restricted Stock UnitsWeighted Average Grant Date Fair Value
Unvested and outstanding as of December 31, 2024932,634 $24.28 
Granted813,841 $10.97 
Released(370,437)$26.09 
Forfeited(28,878)$15.04 
Unvested and outstanding as of March 31, 20251,347,160 $15.94 
Schedule of Share-Based Payment Award, Equity Instruments Other Than Options, Valuation Assumptions
The fair value of the TSR PSUs were derived from a Monte Carlo simulation model that used the following key assumptions:
Valuation date share price$17.57 
Award term (years)1.92
Volatility70.62 %
Correlation coefficient0.3508
Average peer group volatility79.69 %
Average peer group correlation coefficient0.4397
Risk-free interest rate
2.84 %
Schedule of Black-Scholes Option Pricing Model to Estimate Stock-based Compensation Expense for 2020 Employee Stock Purchase Plan The Company used Black-Scholes option pricing model to estimate stock-based compensation expense for the 2020 ESPP with the following assumptions:
  Three Months Ended March 31,
 20252024
Risk-free interest rate4.31%5.27%
Expected term of options (in years)0.500.50
Expected stock price volatility209.54%63.92%
Expected dividends——
Schedule of Classification of Stock-based Compensation Expense
The following table presents the components and classification of stock-based compensation expense for the Company’s stock-based awards for the three months ended March 31, 2025 and 2024 (in thousands):
Three Months Ended March 31,
20252024
Stock options and ESPP$5,961 $6,358 
Restricted stock units2,951 3,246 
Performance-based restricted stock units— 62 
Total stock-based compensation expense$8,912 $9,666 
Research and development expenses$3,702 $3,070 
General and administrative expenses$5,210 $6,596