Merck & Co. Inc. plans to seek supplemental approval for its anti-PD-1 therapy Keytruda in second-line esophageal cancer based on successful data from a Phase III study testing pembrolizumab monotherapy versus physician’s choice of chemotherapy, after the trial showed statistical significance in improving overall survival in patients whose tumors express PD-L1.
The trial was designed to be deemed successful if it proved any of three primary hypotheses pertaining to overall survival...