Japanese healthcare company Daiichi Sankyo Co Ltd (TYO:4568) and US pharmaceutical company Merck & Co Inc (NYSE:MRK), known as MSD outside the US and Canada, revealed on Thursday that they have voluntarily withdrawn their Biologics License Application for patritumab deruxtecan in previously treated, locally advanced or metastatic EGFR-mutated non-small cell lung cancer.

This decision follows topline data from the phase 3 HERTHENA-Lung02 trial, in which overall survival did not meet statistical significance. It was made after discussions with the US Food and Drug Administration and is not related to a prior Complete Response Letter concerning a third-party manufacturing facility.

Patritumab deruxtecan, a specifically engineered HER3-directed DXd antibody drug conjugate, was jointly developed by Daiichi Sankyo and Merck. The HERTHENA-Lung02 trial compared the drug to platinum-based doublet chemotherapy in patients previously treated with a third-generation EGFR tyrosine kinase inhibitor.

Despite the outcome, progression-free survival was statistically significant and will be presented at the 2025 American Society of Clinical Oncology Annual Meeting. The safety profile remained consistent with earlier studies, with no new signals identified.

Daiichi Sankyo continues to analyse biomarkers to refine patient selection and guide future development of the therapy in lung cancer. The broader development programme includes multiple clinical trials across 15 cancer types.