This substudy is part of an umbrella platform study which is designed to evaluate investigational agents with or without pembrolizumab in participants with urothelial carcinoma who are in need of new treatment options. Substudy 04A will enroll participants with locally advanced or mUC whose disease is resistant to treatment with programmed cell death-1/ligand 1 (PD-1/L1) inhibitors. The protocol infrastructure will enable the rolling assignment of investigational treatments.
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.