Daiichi’s lung cancer ADC rejected by FDA in blow to first project under Merck partnership

CAR-T Digest - August 2020

26 June 2024: Daiichi’s lung cancer ADC rejected by FDA in blow to first project under Merck partnership

The FDA rejected Daiichi Sankyo’s and Merck & Co.’s ADC patritumab deruxtecan (HER3-DXd) for treating EGFR-mutated NSCLC after at least two systemic therapies, despite its priority review status
The rejection was due to issues found during an inspection of a contractor’s manufacturing facility, not the drug’s efficacy or safety. The contractor’s identity and specific issues were not disclosed
Daiichi Sankyo and Merck are committed to resolving the manufacturing issues with the FDA and the third-party manufacturer to bring the first HER3-directed medicine to patients
This follows the FDA’s partial clinical hold on BioNTech’s HER3-targeted ADC, BNT326, after three patient deaths in a phase 1 trial. BioNTech is now focusing on lower doses to balance efficacy and safety
HER3-DXd, part of a $4 billion Merck-Daiichi collaboration, showed a 29.8% tumor shrinkage rate and a 6.4-month median response duration in the HERTHENA-Lung01 trial. Daiichi is also running the phase 3 HERTHENA-Lung02 trial and evaluating the drug in breast cancer