NCT05562830 · Merck Sharp & Dohme LLC
A Substudy of Investigational Agents in Programmed Cell Death-1/Ligand 1 (PD-1/L1) Refractory Locally Advanced or Metastatic Urothelial Carcinoma (mUC) (MK-3475-04A)
What this study is about
This substudy is part of an umbrella platform study which is designed to evaluate experimental 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.
View original scientific description
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.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- The main inclusion and
Exclusion criteria
- include but are not limited to the following:
- Histologically or cytologically confirmed diagnosis of locally advanced/unresectable or mUC of the renal pelvis, ureter (upper urinary tract), bladder, or urethra.
- Arm A: PD-1/L1 refractory locally advanced or mUC as evidenced by: EITHER disease progression while on treatment or after treatment with an anti-PD-1/L1 monoclonal antibody (mAb) for locally advanced/unresectable or mUC administered either as monotherapy, or in combination with other checkpoint inhibitors or other therapies OR disease recurrence while on treatment or after treatment with an anti-PD-1/L1 mAb for muscle-invasive urothelial carcinoma (MIUC) administered as monotherapy.
- Arm A: Participants must provide an archival tumor tissue sample or newly obtained core or excisional biopsy of a tumor lesion demonstrating UC, not previously irradiated, and adequate for biomarker evaluation.
- Arm B: PD-1/L1 refractory locally advanced or mUC as evidenced by: EITHER disease progression after treatment with an anti-PD-1/L1 mAb for locally advanced/unresectable or mUC administered either as monotherapy, or in combination with other checkpoint inhibitors or other therapies; OR disease recurrence after treatment with an anti-PD-1/L1 mAb for MIUC administered as monotherapy or in combination with other checkpoint therapies \>12 months after last dose of treatment with an anti-PD-1/L1 mAb.
- Arm B: Participants must provide an archival tumor tissue sample or newly obtained core or excisional biopsy of a tumor lesion from a metastatic site or from a primary tumor that has become locally advanced and not previously irradiated. Exclusion Criteria:
- Known additional nonurothelial malignancy that is progressing or has required active treatment within 3 years prior to study randomization/allocation.
- Received prior systemic anticancer therapy including investigational agents within 4 weeks before randomization/allocation.
- Active infection requiring systemic therapy.
- Received a live or live-attenuated vaccine within 30 days before the first dose of study intervention. Administration of killed vaccines are allowed.
- Known history of human immunodeficiency virus (HIV).
- Known history of hepatitis B or known hepatitis C virus infection.
Where
- Orange, California
- San Francisco, California
- Aurora, Colorado
- Chicago, Illinois
- Indianapolis, Indiana
- St Louis, Missouri
- New York, New York
- Cleveland, Ohio
- Pittsburgh, Pennsylvania
- Salt Lake City, Utah
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 27, 2026 · Source of record for eligibility and locations