Gossamer Bio, Inc.

What they do

Gossamer Bio is focused on the development and commercialization of seralutinib, an inhaled PDGFR, CSF1R and c-KIT inhibitor, for the treatment of pulmonary hypertension, including PAH and PH-ILD. The company has no approved products and has not generated product revenue; its historical revenue reflects collaboration payments, most recently under a now-terminated agreement with Chiesi. In July 2026, Gossamer reacquired worldwide development and commercial rights to seralutinib from Chiesi, giving it full control of development, manufacturing, commercialization, pricing and lifecycle strategy globally.

Revenue drivers

• Seralutinib (GB002) future product sales — Gossamer's primary potential revenue source is seralutinib, currently in development for PAH and PH-ILD; no product revenue has been recognized to date.
• Chiesi collaboration (terminated) — Prior revenue came from a collaboration and license agreement with Chiesi, which was terminated in July 2026; Gossamer received a one-time $5 million payment from Chiesi and no longer shares U.S. profits or receives ex-U.S. royalties.
• Capped royalty obligation to Chiesi — Under the termination agreement, Chiesi is entitled to a capped royalty on worldwide net sales of seralutinib, with no further obligation once the cap is reached, plus payments upon regulatory and commercial milestones.
• No other product or segment revenue — The company has no other products or revenue-generating segments; all revenue to date has been collaboration-related and non-recurring.

Recent performance

For the second quarter of 2026, Gossamer reported revenue of $9.2 million, down from $17.0 million in the first quarter of 2026 and $13.8 million in the fourth quarter of 2025. Annual revenue was $48.5 million in 2025 and $114.7 million in 2024. Net income was negative $170.4 million in 2025 and negative $56.5 million in 2024. As of June 30, 2026, the company had total assets of $76.9 million, total liabilities of $170.9 million, stockholders' deficit of $94.0 million, and cash and equivalents of $41.1 million; the earnings release stated cash, cash equivalents and marketable securities totaled $57.0 million. Operating cash flow was negative $171.3 million in 2025 and negative $3.5 million in 2024.

Strategy

Gossamer's near-term strategy is to advance seralutinib for PAH and pursue regulatory approval as efficiently as possible. Following a Pre-NDA Type B meeting with the FDA in mid-June 2026 and receipt of official minutes, the company plans to submit an NDA for seralutinib in PAH in September 2026, supported by the Phase 3 PROSERA study plus confirmatory evidence from the Phase 2 TORREY study. The company reacquired worldwide rights to seralutinib from Chiesi, consolidating global control and economics, and completed a convertible note exchange that reduced debt by approximately $115.9 million. Gossamer is also evaluating strategic options and resource allocation and strengthening its capital structure; PH-ILD remains an area of focus.

Risks

• Regulatory approval uncertainty — The Phase 3 PROSERA study missed its prespecified alpha threshold (p=0.0320 vs. 0.025), and the FDA may not approve seralutinib based on one adequate and well-controlled study plus confirmatory evidence.
• Need for substantial additional financing — Gossamer has a history of losses, expects additional losses, and will require substantial additional financing to achieve its goals, with cash and marketable securities of $57.0 million as of June 30, 2026.
• Negative stockholders' equity and liabilities exceeding assets — As of June 30, 2026, total liabilities of $170.9 million exceeded total assets of $76.9 million, resulting in a stockholders' deficit of $94.0 million.
• Dependence on a single product candidate — The company depends heavily on the successful development and approval of seralutinib, and failure or delay would materially harm the business.

Outlook

Management states that it remains on track to submit an NDA for seralutinib in PAH in September 2026. If the NDA is accepted for filing, seralutinib could be eligible for an FDA approval decision in the third quarter of 2027. The company also intends to evaluate strategic options and resource allocation while strengthening its capital structure. PH-ILD remains an area of focus for potential future development.