Merck & Co. and Daiichi Sankyo voluntarily withdrew their U.S. Biologics License Application seeking accelerated approval for ifinatamab deruxtecan, or I-DXd, in adults with extensive-stage small-cell lung cancer whose disease progressed after platinum-based chemotherapy. The FDA told the companies that data from the Phase 2 IDeate-Lung01 trial did not meet the requirements for the accelerated-approval pathway. In September 2025, the study reported a 48.2% confirmed objective response rate among 137 previously treated patients, with median duration of response of 5.3 months, median progression-free survival of 4.9 months and median overall survival of 10.3 months. The partners are continuing the Phase 3 IDeate-Lung02 trial against physician-chosen chemotherapy in relapsed disease, along with Phase 3 studies in prostate and esophageal cancers. Merck also agreed to license SciBrunch Therapeutics’ preclinical oral KRAS G12D (ON) inhibitor SPR2015 for an upfront payment of $400 million and potential aggregate payments of $2.13 billion. Merck said it will record a $400 million pretax charge, or about 13 cents per share, in the third quarter of 2026.