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STOCKHOLDERS’ EQUITY (Tables) | 6 Months Ended
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Jun. 30, 2025
Equity [Abstract] |
Schedule of Allocation of Stock-Based Compensation Expense Related to Share-Based Payment Awards | The following table summarizes the stock-based compensation expense included in operating expenses on our condensed consolidated statements of operations related to stock options, restricted stock units, and employee stock purchases for the three and six months ended June 30, 2025 and 2024, which was allocated as follows:
|  | Three Months Ended June 30, |  | Six Months Ended June 30, |  |
(In thousands) |  | 2025 |  | 2024 |  | 2025 |  | 2024 |  |  |  |
Research and development |  | $ | 2,521 |  |  | $ | 4,375 |  |  | $ | 4,917 |  |  | $ | 6,056 |  |  |  |  |
Selling, general and administrative |  | 4,217 |  |  | 8,250 |  |  | 9,230 |  |  | 11,446 |  |  |  |  |
Total stock-based compensation expense |  | $ | 6,738 |  |  | $ | 12,625 |  |  | $ | 14,147 |  |  | $ | 17,502 |  |  |  |  |
Schedule of Assumptions Used to Estimate the Fair Value of Stock Options Granted | The fair value of service-based stock options granted during the six months ended June 30, 2025 and 2024 has been estimated at the date of grant using the Black-Scholes option-pricing model with the following assumptions:
| Six Months Ended June 30,
| 2025 |  | 2024
Dividend yield | 0% |  | 0%
Expected volatility range | 71.96% to 73.94% |  | 82.94% to 86.68%
Risk-free interest rate range | 4.04% to 4.47% |  | 4.05% to 4.62%
Expected term | 6 years |  | 6 years
Schedule of Assumptions Used to Estimate the Fair Value of Employee Stock Purchases Under the Purchase Plan | The fair value of employees’ stock purchase rights during the six months ended June 30, 2025 and 2024 has been estimated using the Black-Scholes option-pricing model with the following assumptions:
| Six Months Ended June 30,
| 2025 |  | 2024
Dividend yield | 0% |  | 0%
Expected volatility range | 44.18% to 93.79% |  | 59.46% to 79.05%
Risk-free interest rate range | 4.17% to 5.10% |  | 4.79% to 5.40%
Expected term range | 6 months to 12 months |  | 6 months to 12 months
Schedule of Stock Options, RSUs and PSOs Activity | The following table summarizes the activity for stock options, RSUs and PSOs as of June 30, 2025:
|  | Stock Options |  | RSUs |  | PSOs
Equity awards outstanding, beginning of year |  | 71,180,260 |  |  | — |  |  | 4,787,107 |
Changes during the year |  |  |  |  |  |
Granted |  | 15,179,500 |  |  | 4,699,750 |  |  | 67,000 |
Exercised |  | (591,321) |  |  | — |  |  | — |
Expired or Forfeited |  | (15,725,482) |  |  | (821,500) |  |  | (73,100) |
Equity outstanding, end of period |  | 70,042,957 |  |  | 3,878,250 |  |  | 4,340,457 |
Unvested portion of equity outstanding, end of period |  | 32,083,468 |  |  | 3,878,250 |  |  | 67,000 |
As of June 30, 2025, total compensation cost related to unvested awards not yet recognized and the weighted-average periods over which the awards are expected to be recognized were as follows ($ in thousands):
|  | Stock Options |  | RSUs |  | PSOs
Unrecognized compensation cost |  | $ | 42,177,124 |  |  | $ | 6,960,870 |  |  | $ | 42,493 |
Expected weighted-average period in years of compensation cost to be recognized |  | 2.75 |  | 3.69 |  | 0.80

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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of employee stock purchase plans, including, but not limited to: (a) expected term, (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://www.xbrl.org/2009/role/commonPracticeRef -Topic 718 -SubTopic 50 -Name Accounting Standards Codification -Publisher FASB -URI https://asc.fasb.org/718-50/tableOfContent Reference 2: 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
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