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 2024, with top-line data anticipated in Q4 2024.

• A second phase 3 registrational study in pulmonary hypertension associated with interstitial lung disease (PH-ILD) will begin in the second half of 2024.

• 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 the study's relevance.

• Long-term extension data show seralutinib efficacy deepens over time, with a 27% reduction in PVR at week 72.

Competitive landscape and efficacy considerations

• Seralutinib is compared to Merck's sotatercept, with a focus on safety and tolerability advantages.

• Six-minute walk distance is the primary endpoint; a 25-30 meter increase is considered a clinical home run without increasing hemoglobin.

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

• Seralutinib is positioned as a third-line therapy, with the potential for longer patient retention compared to sotatercept.

• The market is expected to shift, with a reservoir of sotatercept-refractory patients available at seralutinib launch.

Commercial strategy and market outlook

• Pricing is expected to align with inhaled Tyvaso and low-dose sotatercept, around $325,000 per year.

• Longer duration on therapy is anticipated to drive higher revenue per patient.

• The addressable market for PH-ILD is three times that of PAH, with a potential total market of $10-15 billion.

• No peak sales guidance has been given, pending phase 3 PH-ILD results.

• Partnership with Chiesi Pharmaceuticals provides commercial strength in Europe, with a mid to high teens royalty.