A Phase 2 interventional study of Pembrolizumab and Pembrolizumab/vibostolimab coformulation in Bladder Cancer, sponsored by Merck Sharp & Dohme LLC. Terminated. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-31.
Sponsored by Merck Sharp & Dohme LLC · Phase 2, Interventional, and Treatment
In this study, participants with high risk non-muscle-invasive bladder cancer (NMIBC) unresponsive to Bacillus Calmette Guerin (BCG) therapy and who are considered ineligible for or have refused to undergo radical cystectomy, will receive pembrolizumab therapy or pembrolizumab in combination with other investigational agents. The primary study hypothesis is that treatment with pembrolizumab will result in a clinically meaningful response.
Effective as of Amendment 12, Cohort C was made exploratory, and all Cohort C outcome measures were made exploratory.
1,616 studies on the registry are indexed under Urinary Bladder Neoplasms; 421 are open to participants now.
This study's enrollment of 296 is above the median of 60 across 1,163 interventional studies indexed under Urinary Bladder Neoplasms.
Browse Urinary Bladder Neoplasms studies →Merck Sharp & Dohme LLC is the lead sponsor of 2,114 studies on the registry; 133 are open to participants now.
Of its 489 completed or terminated interventional studies of FDA-regulated products, 362 (74%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion criteria:
Participants with carcinoma-in-situ (CIS) with or without papillary tumors (Cohort A) and participants with papillary tumors only, without CIS (Cohort B) will receive pembrolizumab, 200 mg, intravenously, every 3 weeks (Q3W) for up to 24 months.
Biological: Pembrolizumab
Participants with CIS with or without papillary tumors (Cohort C) will receive either pembrolizumab/vibostolimab or favezelimab/pembrolizumab coformulation intravenously Q3W for up to 24 months
Biological: Pembrolizumab/vibostolimab coformulation · Biological: Favezelimab/pembrolizumab coformulation
Participants with CIS with or without papillary tumors (Cohort A) and participants with papillary tumors only, without CIS (Cohort B) receive pembrolizumab 200mg via IV infusion once every 3 weeks for up to 35 administrations
Also known as: MK-3475, KEYTRUDA
Participants with CIS with or without papillary tumors (Cohort C) receive pembrolizumab/vibostolimab (coformulation of 200 mg pembrolizumab and 200 mg vibostolimab) via IV infusion once every 3 weeks for up to 35 administrations
Also known as: MK-7684A
Participants with CIS with or without papillary tumors (Cohort C) receive favezelimab/pembrolizumab (coformulation of 800mg favezelimab and 200 mg pembrolizumab) via IV infusion once every 3 weeks for up to 35 administrations
Also known as: MK-4280A
Cohort A: Complete Response (CR) Rate of High-Risk Non-Muscle Invasive Bladder Cancer (NMIBC)
The CR rate of high-risk NMIBC is defined as the proportion of participants in the analysis population whose tumors are in response to treatment and who are then free of high-risk NMIBC or worse per central pathology and radiology review.
Time frame: Up to approximately 6 months
Cohort B: 12-month Disease-Free Survival (DFS) Rate of High-Risk NMIBC
DFS of high-risk NMIBC is defined as the time from the first dose to the first occurrence of high-risk NMIBC or worse per central pathology and radiology review. The 12-month DFS rate is the percentage of participants remaining free from high-risk NMIBC or worse at 12 months.
Time frame: Up to approximately 12 months
Cohort A and B: Number of Participants Who Experience an Adverse Event (AE)
An AE is defined as any untoward medical occurrence in a participant or clinical investigation subject administered a pharmaceutical product and which does not necessarily have to have a causal relationship with this treatment.
Time frame: Up to approximately 27 months
Cohort A and B: Number of Participants Who Discontinue Study Treatment Due to an AE
An AE is defined as any untoward medical occurrence in a participant or clinical investigation subject administered a pharmaceutical product and which does not necessarily have to have a causal relationship with this treatment.
Time frame: Up to approximately 24 months
Cohort A: CR Rate of Any Disease
The CR rate of any disease is defined as the proportion of participants in the analysis population whose tumors are in response to treatment and who are then free of any disease or worse per central pathology and radiology review.
Time frame: Up to approximately 6 months
Cohort A: CR Rate of High-Risk NMIBC in Programmed Cell Death 1 (PDL-1) Positive Participants
The CR of high-risk NMIBC is defined as the proportion of PDL-1 positive participants in the analysis population whose tumors are in response to treatment and who are then free of high-risk NMIBC or worse per central pathology and radiology review.
Time frame: Up to approximately 6 months
Cohort A: Duration of Response (DOR)
The DOR is defined as the time from the first documented evidence of CR until the recurrence of disease or worse per clinical pathology and radiology review.
Time frame: Up to approximately 60 months
Cohort A and B: Progression-Free Survival (PFS)
PFS is defined as the time from the first dose to progression to worsening of grade or stage or death or to muscle invasive or metastatic disease or death per central urology, pathology, and radiology review.
Time frame: Up to approximately 60 months
Cohort A and B: Overall Survival (OS)
OS is defined as the time from first dose to death due to any cause.
Time frame: Up to approximately 60 months
Cohort B: DFS Rate of Any Disease
DFS of any disease is defined as the time from the first dose to the first occurrence of any disease or worse per central pathology and radiology review. The DFS rate is the percentage of participants remaining free of any disease or worse.
Time frame: Up to approximately 60 months
Cohort B: 12-month DFS Rate of Any Disease
DFS of any disease is defined as the time from the first dose to the first occurrence of any disease or worse per central pathology and radiology review. The 12-month DFS rate of any disease is the percentage of participants remaining free of any disease or worse at 12 months.
Time frame: Up to approximately 12 months
Cohort B: 12-month DFS Rate of High-Risk NMIBC in PDL-1 Positive Participants
DFS of high-risk NMIBC is defined as the time from the first dose to the first occurrence of high-risk NMIBC or worse per central pathology and radiology review. The 12-month DFS rate is the percentage of participants remaining free from high-risk NMIBC or worse at 12 months. The 12-month DFS rate of high-risk NMIBC in PDL-1 positive participants will be reported.
Time frame: Up to approximately 12 months
No study locations are listed for this record.
Plan to share: Yes — https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
This study is terminated, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Merck Sharp & Dohme LLC