Daiichi Sankyo and Merck withdraw lung cancer drug application

Daiichi Sankyo and Merck & Co. (MSD) have withdrawn their U.S. biologics license application (BLA) for ifinatamab deruxtecan, an antibody drug conjugate intended for adults with extensive-stage small cell lung cancer (ES-SCLC) following progression on platinum-based chemotherapy.

The decision to withdraw the request for accelerated approval from the FDA followed discussions indicating that available evidence, including data from the Phase II IDeate-Lung01 trial, did not support the accelerated approval pathway. While the Phase II trial showed a 48.2% confirmed response rate for a specific dose, the study compared two doses of the drug rather than testing it against an existing treatment, lacking a control group to confirm clinical benefit.

Despite the withdrawal, the companies stated that development of ifinatamab deruxtecan for ES-SCLC will continue. Enrollment is currently nearing completion in the Phase III IDeate-Lung02 trial, which evaluates the drug's safety and efficacy against various chemotherapy options. The results from this larger study will be used for potential future regulatory submissions in the U.S. and other global markets.