XML 30 R21.htm IDEA: XBRL DOCUMENT
v3.23.3

Equity Incentive Plans (Tables) | 9 Months Ended
--- | ---
Sep. 30, 2023
Share-Based Payment Arrangement [Abstract] |
Summary of Stock Option Activity | The following table presents stock option activity under the Plans for the period:
|  | Number of Shares |  |  | Weighted- Average Exercise Price Per Share |  |  | Weighted- Average Remaining Contractual Term (in years) |  |  | Aggregate Intrinsic Value (in thousands) |
Balances as of December 31, 2022 |  |  | 8,152,093 |  |  | $ | 11.92 |  |  |  | 8.09 |  |  | $ | 3,329 |
Stock options granted |  |  | 2,418,450 |  |  | $ | 5.39 |  |  |  |  |  |  |
Stock options exercised |  |  | (55,888 | ) |  | $ | 1.99 |  |  |  |  |  |  |
Stock options forfeited |  |  | (1,179,453 | ) |  | $ | 10.61 |  |  |  |  |  |  |
Balances as of September 30, 2023 |  |  | 9,335,202 |  |  | $ | 10.45 |  |  |  | 7.73 |  |  | $ | 188 |
Exercisable as of September 30, 2023 |  |  | 4,784,184 |  |  | $ | 12.14 |  |  |  | 6.74 |  |  | $ | 183 |
Summary of RSU Activity under 2020 Plan | A summary of RSU activity under the 2020 Plan and related information is as follows:
|  | Number of Shares |  |  | Weighted-Average Grant Date Fair Value Per Share |
Unvested as of December 31, 2022 |  |  | 550,236 |  |  | $ | 5.58 |
Granted |  |  | 249,615 |  |  |  | 5.95 |
Vested |  |  | (160,932 | ) |  |  | 5.29 |
Cancelled |  |  | (105,002 | ) |  |  | 5.58 |
Unvested as of September 30, 2023 |  |  | 533,917 |  |  | $ | 5.84 |
Summary of Stock-Based Compensation Expense | The total stock-based compensation expense related to all equity-based awards recognized in the period was as follows (in thousands):
|  | Three Months Ended September 30, |  |  | Nine Months Ended September 30, |
|  | 2023 |  |  | 2022 |  |  | 2023 |  |  | 2022 |
Research and development |  | $ | 2,243 |  |  | $ | 2,433 |  |  | $ | 6,801 |  |  | $ | 6,509 |
General and administrative |  |  | 2,306 |  |  |  | 2,478 |  |  |  | 7,015 |  |  |  | 7,174 |
Total stock-based compensation expense |  | $ | 4,549 |  |  | $ | 4,911 |  |  | $ | 13,816 |  |  | $ | 13,683 |
Summary of Fair Value of Each Award Issued Estimated on the Date of Grant Using the Black-Scholes Option Pricing Model | The fair value of each award issued was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions:
|  | Three Months Ended September 30, |  | Nine Months Ended September 30,
|  | 2023 |  | 2022 |  | 2023 |  | 2022
Expected term (in years) |  | 6.08 |  | 5.77 - 6.08 |  | 5.50 - 6.08 |  | 5.50 - 6.08
Expected volatility |  | 81.80% - 81.90% |  | 81.70% - 82.70% |  | 81.20% - 82.40% |  | 78.80% - 82.80%
Risk-free interest rate |  | 4.20% - 4.42% |  | 2.92% - 3.61% |  | 3.47% - 4.42% |  | 1.49% - 3.61%
Dividend yield |  | — |  | — |  | — |  | —

X
- References No definition available. + Details
Name: | us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of cost recognized for award under share-based payment arrangement by plan. Includes, but is not limited to, related tax benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
Name: | us-gaap_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the changes in outstanding nonvested restricted stock units. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
Name: | us-gaap_ScheduleOfNonvestedRestrictedStockUnitsActivityTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -SubTopic 10 -Topic 718 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (e) -SubTopic 10 -Topic 718 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
Name: | us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 718 -SubTopic 10 -Subparagraph (f)(2) -Name Accounting Standards Codification -Paragraph 2 -Section 50 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
Name: | us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration