This study will assess whether post-surgery therapy with pembrolizumab improves recurrence-free survival (RFS) as compared to placebo for high-risk participants with melanoma (Stage IIIA \[\> 1 mm metastasis\], IIIB and IIIC). The study will also assess whether pembrolizumab improves RFS versus placebo in the subgroup of participants with programmed cell death-ligand 1 (PD-L1)-positive tumor expression. Participants will be stratified for stage of disease and region and then will be randomly assigned to receive either pembrolizumab or placebo as post-surgery therapy in Part 1. In Part 2, participants who experience a disease recurrence are eligible for pembrolizumab treatment (if treated with placebo in Part 1) or pembrolizumab rechallenge (if treated with pembrolizumab in Part 1).
Phase 3 trials are pivotal studies with large patient populations (hundreds to thousands) designed to prove efficacy and safety for FDA submission. A successful Phase 3 readout is typically the last major hurdle before a New Drug Application (NDA) or BLA filing.
Enrollment is complete. The trial is in its follow-up or data collection phase — a readout may occur on or near the primary completion date.
Merck & Co (MRK) is the sponsoring company for this trial. BiotechSign currently grades this company F (35/100) based on composite catalyst signals across its full pipeline. This trial is one data point in that overall catalyst picture.