US pharmaceutical company Amgen (NASDAQ:AMGN) announced on Monday that the Phase 3 FORTITUDE-101 clinical trial evaluating first-line bemarituzumab plus chemotherapy (mFOLFOX6) met its primary endpoint of overall survival (OS) at a pre-specified interim analysis.

The company says that Bemarituzumab plus chemotherapy demonstrated a statistically significant and clinically meaningful improvement in OS as compared to placebo plus chemotherapy in people living with unresectable locally advanced or metastatic gastric or gastroesophageal junction (G/GEJ) cancer with FGFR2b overexpression and who are non-HER2 positive. FGFR2b overexpression was defined as 2+/3+ staining in greater than 10% of tumour cells by centrally performed immunohistochemistry (IHC) testing.

FORTITUDE-101 was conducted with the support of Zai Lab. Zai Lab holds co-development and commercialisation rights for bemarituzumab for mainland China, Hong Kong, Macau and Taiwan.

"Most patients with gastric cancer are diagnosed at an advanced stage, with poor prognosis, low survival rates and limited therapeutic options," said Jay Bradner, M.D., Amgen executive vice president of Research and Development. "These first positive top-line results of an FGFR2b targeted monoclonal antibody from our Phase 3 FORTITUDE-101 study mark a meaningful advance in the development of effective targeted therapy for gastric cancer."

A Phase 3 study of bemarituzumab plus chemotherapy and nivolumab is also ongoing in patients with first-line gastric cancer, with a data readout anticipated in the second half of 2025.

FORTITUDE-101 is a randomised, multi-centre, double-blind, placebo-controlled Phase 3 study of bemarituzumab plus mFOLFOX6 versus placebo plus mFOLFOX6 as first-line therapy in advanced G/GEJ cancer with FGFR2b overexpression.