NEW YORK – Merck and Daiichi Sankyo said Tuesday that they plan to meet with regulators to discuss new data from the HERTHENA-Lung02 trial evaluating their HER3-directed antibody-drug conjugate, patritumab deruxtecan.
In the Phase III trial, the antibody-drug conjugate improved progression-free survival outcomes among EGFR-mutated non-small cell lung cancer patients as compared to chemotherapy.
The trial includes 586 patients with locally advanced or metastatic, EGFR-mutated NSCLC who received prior EFGR tyrosine kinase inhibitors. Although the trial met its primary endpoint of improved progression-free survival, patients will continue to be monitored as Merck and Daiichi Sankyo determine whether the drug also improved overall survival.
Last year, the drugmakers, which have been jointly developing patritumab deruxtecan following a 2023 licensing deal, filed for US Food and Drug Administration approval for the agent based on the Phase II HERTHENA-Lung01 trial. In that study, EGFR-mutated NSCLC patients must have received prior EGFR TKIs as well as prior chemo.
Then, in June, Merck and Daiichi Sankyo said they received a complete response letter from the FDA flagging manufacturing issues at a third-party facility. The drugmakers said the letter did not concern any of the antibody-drug conjugate's clinical data and that they were working with the FDA to address the issues.