Merck and Daiichi Sankyo have voluntarily withdrawn their U.S. application seeking accelerated approval for ifinatamab deruxtecan, an experimental therapy for adults with extensive-stage small cell lung cancer whose disease worsened after standard chemotherapy. The decision followed discussions with the U.S. Food and Drug Administration, which determined that data from a mid-stage clinical study did not satisfy the requirements for an early approval. The application had covered certain previously treated patients, and the development was identified as MRK stock news.