Amgen's Partner Zai Lab Reports Mixed Results for Gastric Cancer Treatment Trial

Amgen's stock dipped after its partner, Zai Lab, updated the late-stage trial of bemarituzumab for gastric cancer treatment. The interim analysis showed that the therapy combined with chemotherapy was effective in first-line gastric cancer treatment.

Amgen (NASDAQ: AMGN) stock experienced a dip on Wednesday following an update from its partner, Zai Lab (NASDAQ: ZLAB), regarding the late-stage trial of bemarituzumab combined with chemotherapy for gastric cancer treatment. The interim analysis of the trial, which focused on first-line gastric cancer treatment, revealed a significant improvement in overall survival when compared to chemotherapy alone. However, the final analysis showed that the previously noted survival advantage had diminished. Zai Lab holds the rights to develop and sell bemarituzumab, a monoclonal antibody, in Mainland China, Hong Kong, Macau, and Taiwan. In light of these findings, Zai Lab plans to wait for the results of the FORTITUDE-102 trial, which is assessing bemarituzumab in combination with nivolumab and chemotherapy for the same patient group, before proceeding with regulatory submissions. The results from the FORTITUDE-102 trial are expected by late 2025 or early 2026. Amgen stock is down about 1% today [1].

This update highlights the ongoing challenges and complexities in developing effective cancer treatments. Bemarituzumab, a monoclonal antibody, has shown promise in initial trials but faced setbacks in the final analysis. The delay in regulatory submissions due to the need for further trials underscores the cautious approach taken by Zai Lab and Amgen. The market's reaction to this news reflects investor concerns about the drug's efficacy and the potential delays in commercialization.

The gastric cancer market is experiencing significant growth and innovation, with numerous companies working on developing novel treatments. As of March 2025, the FDA awarded orphan drug designation to HLX22, a novel anti-HER2 monoclonal antibody, for the treatment of gastric cancer. This status offers multiple development incentives, such as tax credits for clinical trial expenses, exemption from new drug application fees, and seven years of market exclusivity once approved [2]. These incentives are designed to speed up the development and availability of HLX22, helping patients—especially those with HER2-positive metastatic gastric (GI) or gastroesophageal junction (GEJ) cancer—gain earlier access to this therapy.

The gastric cancer pipeline is diverse, with therapies at various stages of development. Companies like Eli Lilly and Company, BeiGene, and Hutchison MediPharma are among the key players working on innovative treatments. The market's growth is driven by increasing patient numbers and awareness, but challenges such as late diagnosis and longer treatment durations persist [2].

In conclusion, the update from Zai Lab regarding bemarituzumab highlights the complexities and uncertainties in developing effective cancer treatments. The market's reaction reflects investor concerns about the drug's efficacy and potential delays. The gastric cancer pipeline is vibrant, with numerous companies working on innovative treatments, but significant challenges remain.

References:
[1] https://seekingalpha.com/news/4491863-amgen-dips-after-trial-update-for-zai-lab-partnered-gastric-cancer-therapy
[2] https://www.barchart.com/story/news/34569734/gastric-cancer-pipeline-2025-latest-fda-approvals-clinical-trials-and-emerging-therapies-assessment-by-delveinsight-eli-lilly-and-company-beigene-hutchison-medipharma-astellas-pharma-henlix