Update on Amgen’s bemarituzumab Phase 3 FORTITUDE-101 Study evaluating bemarituzumab in combination with chemotherapy in first-line gastric cancer

On September 3^rd, Amgen and Zai Lab announced that the final analysis of P3 FORTITUDE-101 (NCT05052801) evaluating bemarituzumab (anti-FGFR2b) + chemotherapy (mFOLFOX6) in 1L HER2-negative FGFR2b-positive GC/GEJC has been completed and that the magnitude of the previously observed survival benefit has decreased.

• Although FORTITUDE-101 may further segment the 1L HER2 GC/GEJC market, the reduced magnitude of survival benefit at final analysis and the ocular toxicities may hinder bema’s adoption
  • Per available literature and previous Amgen commentary, FGFR2b protein overexpression is seen in ~38% of patients with advanced G/GEJ cancer 
• in June 2025, Amgen announced positive interim analysis from P3 FORTITUDE-101 stating that the regimen demonstrated a statistically significant improvement in OS over placebo + mFOLFOX6 with ocular toxicities being observed with greater frequency and severity than those seen in the P2 FIGHT study
  • Detailed results from both the interim analysis and final analysis are likely to be present at ESMO 2025 as LBA (titles expected September 20^th)
• Data from P1b/3 FORTITUDE-102 ((bema + nivolumab (Opdivo, anti-PD-1) + chemo in 1L HER2-negative FGFR2b-positive GC/GEJC is now anticipated by the end of 2025 or the first half of 2026. Based on the updated results of the FORTITUDE-101 trial, Zai Lab intends to await the results of FORTITUDE-102, evaluating bemarituzumab in combination with nivolumab and chemotherapy in the same patient population, prior to regulatory filing.
  • Combined global filing for FORTITUDE-101 and FORTITUDE-102 is expected for these two studies, with earliest potential US approval in Q1 2027 and EU approval in Q2 2027