Gossamer Bio Inc. filed SEC Form 8-K: Regulation FD Disclosure, Other Events, Financial Statements and Exhibits
$GOSS
Biotechnology: Pharmaceutical Preparations
Health Care
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 8-K
CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
Date of Report (Date of earliest event reported): June 16, 2025
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Item 7.01 Regulation FD Disclosure.
On June 16, 2025, Gossamer Bio, Inc. (the “Company”) issued a press release reporting the completion of enrollment for the ongoing, global registrational Phase 3 PROSERA Study evaluating seralutinib in Functional Class II and III pulmonary arterial hypertension (PAH) patients discussed in Item 8.01 below. The full text of the press release is attached as Exhibit 99.1 to this Current Report.
The information contained in this Item 7.01, including in Exhibit 99.1 hereto, is being “furnished” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and is not deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, except as shall be expressly set forth by specific reference in such a filing.
Item 8.01 Other Events.
On June 16, 2025, the Company announced the completion of enrollment for the ongoing, global registrational Phase 3 PROSERA Study evaluating seralutinib in Functional Class II and III PAH patients. The patient population enrolled in PROSERA aligns with the target demographic, as evidenced by the preliminary baseline characteristics. The PROSERA Study utilizes enrichment criteria, including the REVEAL Lite 2 Risk Score and other criteria, to identify patients more likely to show a greater magnitude of effect on 6MWD at week 24, as informed by the Phase 2 TORREY study.
Seralutinib Clinical Trial Baseline Characteristics: Phase 3 PROSERA Study v. Phase 2 TORREY Study
| PROSERA Phase 3* | TORREY Phase 2 | |||||||
| Study Participants | n = 390 | n = 86 | ||||||
| Mean 6MWD | 374 meters | 408 meters | ||||||
| Mean NT-proBNP | 987 ng/L | 628 ng/L | ||||||
| Functional Class III Patients | 289 (74%) | 36 (42%) | ||||||
| Geographic Distribution | North America: 75 (19%) Rest of World: 315 (81%) | North America: 59 (69%) Rest of World: 27 (31%) | ||||||
*Baseline characteristics are preliminary and subject to change. | ||||||||
The Company expects to announce topline results from the ongoing Phase 3 PROSERA Study in February 2026.
Item 9.01 Financial Statements and Exhibits.
(d) Exhibits.
| Exhibit Number | Description | |||||||
| 99.1 | Press Release dated June 16, 2025 | |||||||
| 101 | Cover Page Interactive Data File (embedded within the Inline XBRL document) | |||||||
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SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.
| GOSSAMER BIO, INC. | |||||||||||
| Date: June 16, 2025 | By: | /s/ Bryan Giraudo | |||||||||
| Bryan Giraudo | |||||||||||
| Chief Financial Officer and Chief Operating Officer | |||||||||||
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