This study is a substudy being conducted under one pembrolizumab umbrella master study KEYMAKER-U04. The substudy will consist of 2 parts. Part 1 will evaluate the safety and preliminary efficacy of sacituzumab tirumotecan plus enfortumab vedotin (EV). Part 2 will be based on Part 1 results and will evaluate the efficacy, pharmacokinetics, and safety of sacituzumab tirumotecan plus EV in combination with pembrolizumab in participants with advanced urothelial carcinoma.
Phase 1 trials primarily test safety and dosing in a small number of participants (typically 20–100). Results do not yet speak to efficacy. FDA approval is typically many years away from this stage.
Phase 2 trials begin testing efficacy in a larger patient group (100–300). This is often where biotech binary events occur — positive Phase 2 data can significantly advance a company's pipeline narrative, while failures can be terminal for a program.
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.