Gossamer Bio (GOSS) Barclays 27th Annual Global Healthcare Conference 2025 summary

Clinical development updates

• Enrollment for the phase 3 study in pulmonary arterial hypertension (PAH) is expected to complete in Q2, with top-line data anticipated in Q4 of this year.

• A second phase 3 study in pulmonary hypertension associated with interstitial lung disease (PH-ILD) will begin in the second half of the year.

• Approval and launch for PAH are targeted for 2027, with PH-ILD launch expected in 2029.

• The enrichment strategy using the REVEAL Lite Risk Score is successfully enrolling sicker patients, improving trial relevance.

• Phase 2 open-label extension data show deepening efficacy over time, with a 27% reduction in PVR at week 72.

Competitive landscape and clinical differentiation

• Seralutinib is positioned as best in class for safety and tolerability, with mild adverse events reported.

• The drug is expected to be used as a third-line therapy, with potential to keep patients on treatment for multiple years.

• Few patients in the current study are on background sotatercept due to limited availability and side effect management challenges.

• The clinical community is debating the impact of hemoglobin increases seen with competing therapies, which seralutinib avoids.

• A 25-30 meter increase in six-minute walk distance is considered a home run, achieved without increasing hemoglobin.

Market outlook and commercialization

• The PAH market is expected to be favorable for seralutinib at launch, with a reservoir of patients refractory to or intolerant of sotatercept.

• Seralutinib pricing is expected to align with inhaled Tyvaso and low-dose sotatercept, around $325,000 annually.

• Revenue per patient is projected to be higher due to longer treatment duration.

• The total addressable market for PAH and PH-ILD is estimated at $10-15 billion, with potential for majority market share.

• Partnership with Chiesi Pharmaceuticals provides strong commercialization support in Europe, with valuable royalty streams.