Gossamer Bio shares plunged 12.86% in pre-market trading due to operational and strategic setbacks.

Dec. 24, 2025 10:15 AM EST - Gossamer Bio shares plunged 12.86% in pre-market trading as investor sentiment deteriorated following a series of operational and strategic setbacks. The steep decline reflects mounting concerns over the biotech firm's pipeline progress and capital structure resilience.

Recent disclosures highlighted delays in key clinical trials for its lead asset, ITX-150, with revised timelines pushing potential Phase III initiation into 2026. Additionally, the company announced the departure of its chief medical officer, raising questions about leadership continuity during critical development phases. Analysts noted these developments compound existing challenges related to its complex equity financing arrangements.

Short-term technical indicators show the stock has broken below key support levels, with bearish momentum intensifying as year-end liquidity constraints tighten in the biotech sector. Institutional positioning data suggests increased short interest has emerged since late November, aligning with the recent downward trend.

While Gossamer maintains its $1.2B cash runway through mid-2027, market participants are recalibrating risk premiums given the extended timeline to potential value realization. The selloff underscores the sector's sensitivity to execution risks in late-stage development programs.