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Pay vs Performance Disclosure - USD ($) | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Pay vs Performance Disclosure |  |  |
Pay vs Performance Disclosure, Table |
Year (1) | Summary Compensation Table Total for PEO ($) |  | Compensation Actually Paid to PEO ($)(2) |  | Average Summary Compensation Table Total for Non-PEO NEOs ($) |  | Average Compensation Actually Paid to Non-PEO NEOs ($)(2) |  | Value of Initial Fixed $100 Investment Based on: Total Shareholder Return ($) |  | Net Income (Loss) ($)
2024 | 2,005,432 |  | 1,859,722 |  | 1,118,479 |  | 1,062,307 |  | 8 |  | (56,528,000)
2023 | 2,095,988 |  | 1,592,883 |  | 1,309,364 |  | 1,205,267 |  | 9 |  | (179,817,000)
2022 | 7,262,410 |  | (1,906,300) |  | 2,875,322 |  | (383,116) |  | 22 |  | (229,378,000)
Named Executive Officers, Footnote | The PEO in all reporting years is Faheem Hasnain. The non-PEO NEOs in the 2024 reporting year are Bryan Giraudo and Richard Aranda, M.D. The non-PEO NEOs in the 2023 reporting year are Bryan Giraudo and Bob Smith. The non-PEO NEOs in the 2022 reporting year are Bryan Giraudo and Richard Aranda, M.D. |  |
PEO Total Compensation Amount | $ 2,005,432 | $ 2,095,988 | $ 7,262,410
PEO Actually Paid Compensation Amount | $ 1,859,722 | 1,592,883 | (1,906,300)
Adjustment To PEO Compensation, Footnote | Amounts represent CAP to our PEO and the average CAP to our remaining NEOs for the relevant fiscal year, as determined under SEC rules (and described below). CAP to our NEOs represents the “Total” compensation reported in the SCT for the applicable fiscal year, as adjusted as follows:
| 2022 | 2023 | 2024
Adjustments(a) | PEO | Average Non-PEO NEOs | PEO | Average Non-PEO NEOs | PEO | Average Non-PEO NEOs
Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY | $(6,359,885) | $(2,217,405) | $(1,185,725) | $(887,420) | $(1,043,438) | $(409,922)
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End | 1,114,194 | 381,335 | 1,163,964 | 697,241 | 914,944 | 359,442
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Vested during Applicable FY, determined as of Vesting Date | — | — | — | — | — | —
Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End | (2,681,136) | (1,182,532) | (454,994) | (64,086) | (53,304) | (14,259)
Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date | (1,241,883) | (239,836) | (26,350) | 57,086 | 36,087 | 8,567
Deduction of ASC 718 Fair Value of Awards Granted during Prior FY that were Forfeited during Applicable FY, determined as of Prior FY End | — | — | — | (48,564) | — | —
Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date | — | — | — | — | — | —
Increase based on Incremental Fair Value of Options/SARs Modified during Applicable FY | — | — | — | 141,646 | — | —
TOTAL ADJUSTMENTS | $(9,168,710) | $(3,258,438) | $(503,105) | $(104,097) | $(145,711) | $(56,172)
(a) The fair value of stock options reported for CAP purposes in the Adjustments table is estimated using a Black-Scholes and Monte Carlo option pricing models. These models use both historical data and current market data to estimate the fair value of options and requires several assumptions. The assumptions used in estimating fair value for options (other than Mr. Hasnain’s performance-based options) included in the adjustments calculation are as follows:
Year |  | 2022 |  | 2023 |  | 2024
Volatility |  | 62.29 - 77.22% |  | 62.34 - 131.17% |  | 101.12 - 134.90%
Expected life (in years) |  | 2.09 - 5.79 years |  | 1.96 - 6.01 years |  | 2.08 - 5.08 years
Expected dividend yield |  | —% |  | —% |  | —%
Risk-free rate |  | 0.73 - 4.72% |  | 3.37 - 5.04% |  | 3.42 - 4.85%
The assumptions used in estimating the fair value of Mr. Hasnain’s performance-based options granted in May 2023, which contain both service-based and market-based vesting conditions, as of the last day of 2024, was determined using the Geometric Brownian Motion/Monte Carlo model and the following assumptions: the company’s common stock price as of December 31, 2023 of $0.91; a six-year continuously compounded equivalent risk-free rate of 3.86%; an expected stock price volatility of 103.89%; a dividend yield of 0%; and an expected term of approximately 6 years. The assumptions used in estimating the fair value of Mr. Hasnain’s performance-based options granted in May 2023, which contain both service-based and market-based vesting conditions, as of the last day of 2024, was determined using the Geometric Brownian Motion/Monte Carlo model and the following assumptions: the company’s common stock price as of December 31, 2024 of $0.90; a five-year continuously compounded equivalent risk-free rate of 4.38%; an expected stock price volatility of 101.19%; a dividend yield of 0%; and an expected term of approximately five years. |  |
Non-PEO NEO Average Total Compensation Amount | $ 1,118,479 | 1,309,364 | 2,875,322
Non-PEO NEO Average Compensation Actually Paid Amount | $ 1,062,307 | 1,205,267 | (383,116)
Adjustment to Non-PEO NEO Compensation Footnote | Amounts represent CAP to our PEO and the average CAP to our remaining NEOs for the relevant fiscal year, as determined under SEC rules (and described below). CAP to our NEOs represents the “Total” compensation reported in the SCT for the applicable fiscal year, as adjusted as follows:
| 2022 | 2023 | 2024
Adjustments(a) | PEO | Average Non-PEO NEOs | PEO | Average Non-PEO NEOs | PEO | Average Non-PEO NEOs
Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY | $(6,359,885) | $(2,217,405) | $(1,185,725) | $(887,420) | $(1,043,438) | $(409,922)
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End | 1,114,194 | 381,335 | 1,163,964 | 697,241 | 914,944 | 359,442
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Vested during Applicable FY, determined as of Vesting Date | — | — | — | — | — | —
Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End | (2,681,136) | (1,182,532) | (454,994) | (64,086) | (53,304) | (14,259)
Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date | (1,241,883) | (239,836) | (26,350) | 57,086 | 36,087 | 8,567
Deduction of ASC 718 Fair Value of Awards Granted during Prior FY that were Forfeited during Applicable FY, determined as of Prior FY End | — | — | — | (48,564) | — | —
Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date | — | — | — | — | — | —
Increase based on Incremental Fair Value of Options/SARs Modified during Applicable FY | — | — | — | 141,646 | — | —
TOTAL ADJUSTMENTS | $(9,168,710) | $(3,258,438) | $(503,105) | $(104,097) | $(145,711) | $(56,172)
(a) The fair value of stock options reported for CAP purposes in the Adjustments table is estimated using a Black-Scholes and Monte Carlo option pricing models. These models use both historical data and current market data to estimate the fair value of options and requires several assumptions. The assumptions used in estimating fair value for options (other than Mr. Hasnain’s performance-based options) included in the adjustments calculation are as follows:
Year |  | 2022 |  | 2023 |  | 2024
Volatility |  | 62.29 - 77.22% |  | 62.34 - 131.17% |  | 101.12 - 134.90%
Expected life (in years) |  | 2.09 - 5.79 years |  | 1.96 - 6.01 years |  | 2.08 - 5.08 years
Expected dividend yield |  | —% |  | —% |  | —%
Risk-free rate |  | 0.73 - 4.72% |  | 3.37 - 5.04% |  | 3.42 - 4.85%
The assumptions used in estimating the fair value of Mr. Hasnain’s performance-based options granted in May 2023, which contain both service-based and market-based vesting conditions, as of the last day of 2024, was determined using the Geometric Brownian Motion/Monte Carlo model and the following assumptions: the company’s common stock price as of December 31, 2023 of $0.91; a six-year continuously compounded equivalent risk-free rate of 3.86%; an expected stock price volatility of 103.89%; a dividend yield of 0%; and an expected term of approximately 6 years. The assumptions used in estimating the fair value of Mr. Hasnain’s performance-based options granted in May 2023, which contain both service-based and market-based vesting conditions, as of the last day of 2024, was determined using the Geometric Brownian Motion/Monte Carlo model and the following assumptions: the company’s common stock price as of December 31, 2024 of $0.90; a five-year continuously compounded equivalent risk-free rate of 4.38%; an expected stock price volatility of 101.19%; a dividend yield of 0%; and an expected term of approximately five years. |  |
Compensation Actually Paid vs. Total Shareholder Return | Relationship between CAP and TSR The graphs below reflect the relationship between the PEO and Average Non-PEO NEO CAP and the company’s cumulative indexed Total Shareholder Return, or TSR, (assuming an initial fixed investment of $100) for the fiscal years ended December 31, 2022, 2023 and 2024: |  |
Compensation Actually Paid vs. Net Income | Relationship between CAP and Net Income (Loss) The graph below reflects the relationship between the PEO and Average Non-PEO NEO CAP and the company’s Net Income (Loss) for the fiscal years ended December 31, 2022, 2023 and 2024: |  |
Total Shareholder Return Amount | $ 8 | 9 | 22
Net Income (Loss) | $ (56,528,000) | $ (179,817,000) | $ (229,378,000)
PEO Name | Faheem Hasnain |  |
Fair Value Assumptions, Volatility Rate, Minimum | 101.12% | 62.34% | 62.29%
Fair Value Assumptions, Volatility Rate, Maximum | 134.90% | 131.17% | 77.22%
Fair Value Assumptions, Expected Term, Minimum | 2 years 29 days | 1 year 11 months 15 days | 2 years 1 month 2 days
Fair Value Assumptions, Expected Term, Maximum | 5 years 29 days | 6 years 3 days | 5 years 9 months 14 days
Fair Value Assumptions, Expected Dividend Rate | 0.00% | 0.00% | 0.00%
Fair Value Assumptions, Risk Free Interest Rate, Minimum | 4.85% | 5.04% | 0.73%
Fair Value Assumptions, Risk Free Interest Rate, Maximum | 3.42% | 3.37% | 4.72%
Faheem Hasnain [Member] |  |  |
Pay vs Performance Disclosure |  |  |
Fair Value Assumptions, Expected Dividend Rate | 0.00% | 0.00% |
Fair Value Assumptions, Common Stock Price | $ 0.90 | $ 0.91 |
Fair Value Assumptions, Risk Free Interest Rate | 4.38% | 3.86% |
Fair Value Assumptions, Volatility Rate | 101.19% | 103.89% |
Fair Value Assumptions, Expected Term | 5 years | 6 years |
PEO | Equity Awards Adjustments |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | $ (145,711) | $ (503,105) | $ (9,168,710)
PEO | Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | (1,043,438) | (1,185,725) | (6,359,885)
PEO | Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 914,944 | 1,163,964 | 1,114,194
PEO | Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | (53,304) | (454,994) | (2,681,136)
PEO | Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 0 | 0 | 0
PEO | Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 36,087 | (26,350) | (1,241,883)
PEO | Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 0 | 0 | 0
PEO | Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 0 | 0 | 0
PEO | Equity Awards Modified During The Year [Member] |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 0 | 0 | 0
Non-PEO NEO | Equity Awards Adjustments |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | (56,172) | (104,097) | (3,258,438)
Non-PEO NEO | Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | (409,922) | (887,420) | (2,217,405)
Non-PEO NEO | Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 359,442 | 697,241 | 381,335
Non-PEO NEO | Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | (14,259) | (64,086) | (1,182,532)
Non-PEO NEO | Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 0 | 0 | 0
Non-PEO NEO | Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 8,567 | 57,086 | (239,836)
Non-PEO NEO | Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 0 | (48,564) | 0
Non-PEO NEO | Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | 0 | 0 | 0
Non-PEO NEO | Equity Awards Modified During The Year [Member] |  |  |
Pay vs Performance Disclosure |  |  |
Adjustment to Compensation, Amount | $ 0 | $ 141,646 | $ 0

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