| Stockholders' Equity |
(10) Stockholders’ Equity In November 2023, the Company filed an automatic shelf registration statement with the SEC to register for sale any combination of the types of securities described in the shelf registration statement, including shares of its common stock. On February 26, 2024, the Company entered into a controlled equity offering sales agreement (“ATM Agreement”) with Cantor Fitzgerald & Co. (“Cantor”) to allow the Company to issue and sell shares of its common stock from time to time through Cantor, acting as agent. At September 30, 2026, the Company had registered $300.0 million of its common stock to be sold pursuant to the Company’s ATM Agreement, all of which remained unsold as of that date. The Company’s shelf registration statement expired on November 3, 2026, and no shares were sold under the ATM Agreement prior to such expiration. In April 2026, the Company issued 11,896,750 shares of its common stock in an underwritten public offering resulting in net proceeds to the Company of $323.8 million, after deducting underwriting fees and offering expenses. The changes in Stockholders’ Equity during the three and nine months ended September 30, 2026 and 2025 are summarized below: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Accumulated | | | | | | | | | Common | | Common | | Additional | | Other | | | | | Total | | | Stock | | Stock Par | | Paid-In | | Comprehensive | | Accumulated | | Stockholders’ | | | Shares | | Value | | Capital | | Income | | Deficit | | Equity | | | | (In thousands, except share amounts) | Consolidated balance at December 31, 2025 | | 66,549,442 | | $ | 67 | | $ | 2,337,453 | | $ | 3,626 | | $ | (1,813,981) | | $ | 527,165 | Shares issued under stock option and employee stock purchase plans | | 19,529 | | | — | | | 327 | | | — | | | — | | | 327 | Stock-based compensation | | — | | | — | | | 8,523 | | | — | | | — | | | 8,523 | Unrealized loss on marketable securities | | — | | | — | | | — | | | (1,104) | | | — | | | (1,104) | Net loss | | — | | | — | | | — | | | — | | | (78,685) | | | (78,685) | Consolidated balance at March 31, 2026 | | 66,568,971 | | $ | 67 | | $ | 2,346,303 | | $ | 2,522 | | $ | (1,892,666) | | $ | 456,226 | Shares issued under stock option and employee stock purchase plans | | 34,452 | | | — | | | 825 | | | — | | | — | | | 825 | Shares issued in underwritten offering, net | | 11,896,750 | | | 12 | | | 323,820 | | | — | | | — | | | 323,832 | Stock-based compensation | | — | | | — | | | 8,408 | | | — | | | — | | | 8,408 | Unrealized loss on marketable securities | | — | | | — | | | — | | | (1,224) | | | — | | | (1,224) | Net loss | | — | | | — | | | — | | | — | | | (73,503) | | | (73,503) | Consolidated balance at June 30, 2026 | | 78,500,173 | | $ | 79 | | $ | 2,679,356 | | $ | 1,298 | | $ | (1,966,169) | | $ | 714,564 | Shares issued under stock option and employee stock purchase plans | | 34,265 | | | — | | | 1,115 | | | — | | | — | | | 1,115 | Stock-based compensation | | — | | | — | | | 10,974 | | | — | | | — | | | 10,974 | Unrealized loss on marketable securities | | — | | | — | | | — | | | (1,627) | | | — | | | (1,627) | Net loss | | — | | | — | | | — | | | — | | | (75,557) | | | (75,557) | Consolidated balance at September 30, 2026 | | 78,534,438 | | $ | 79 | | $ | 2,691,445 | | $ | (329) | | $ | (2,041,726) | | $ | 649,469 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Accumulated | | | | | | | | | Common | | Common | | Additional | | Other | | | | | Total | | | Stock | | Stock Par | | Paid-In | | Comprehensive | | Accumulated | | Stockholders’ | | | Shares | | Value | | Capital | | Income | | Deficit | | Equity | | | | (In thousands, except share amounts) | Consolidated balance at December 31, 2024 | | 66,374,549 | | $ | 66 | | $ | 2,298,849 | | $ | 3,314 | | $ | (1,555,224) | | $ | 747,005 | Shares issued under stock option and employee stock purchase plans | | 9,642 | | | — | | | 202 | | | — | | | — | | | 202 | Stock-based compensation | | — | | | — | | | 9,316 | | | — | | | — | | | 9,316 | Unrealized gain on marketable securities | | — | | | — | | | — | | | 254 | | | — | | | 254 | Net loss | | — | | | — | | | — | | | — | | | (53,796) | | | (53,796) | Consolidated balance at March 31, 2025 | | 66,384,191 | | $ | 66 | | $ | 2,308,367 | | $ | 3,568 | | $ | (1,609,020) | | $ | 702,981 | Shares issued under stock option and employee stock purchase plans | | 10,050 | | | — | | | 63 | | | — | | | — | | | 63 | Stock-based compensation | | — | | | — | | | 9,191 | | | — | | | — | | | 9,191 | Unrealized loss on marketable securities | | — | | | — | | | — | | | (229) | | | — | | | (229) | Net loss | | — | | | — | | | — | | | — | | | (56,600) | | | (56,600) | Consolidated balance at June 30, 2025 | | 66,394,241 | | $ | 66 | | $ | 2,317,621 | | $ | 3,339 | | $ | (1,665,620) | | $ | 655,406 | Shares issued under stock option and employee stock purchase plans | | 52,605 | | | — | | | 774 | | | — | | | — | | | 774 | Stock-based compensation | | — | | | — | | | 8,801 | | | — | | | — | | | 8,801 | Unrealized gain on marketable securities | | — | | | — | | | — | | | 426 | | | — | | | 426 | Net loss | | — | | | — | | | — | | | — | | | (67,044) | | | (67,044) | Consolidated balance at September 30, 2025 | | 66,446,846 | | $ | 66 | | $ | 2,327,196 | | $ | 3,765 | | $ | (1,732,664) | | $ | 598,363 |
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