Perioperative Pembrolizumab (MK-3475) Plus Neoadjuvant Chemotherapy Versus Perioperative Placebo Plus Neoadjuvant Chemotherapy for Cisplatin-eligible Muscle-invasive Bladder Cancer (MIBC) (MK-3475-866/KEYNOTE-866)
Public ClinicalTrials.gov record NCT03924856. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.
Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.
Official title
A Phase 3, Randomized, Double-blind Study to Evaluate Perioperative Pembrolizumab (MK-3475) + Neoadjuvant Chemotherapy Versus Perioperative Placebo + Neoadjuvant Chemotherapy in Cisplatin-eligible Participants With Muscle-invasive Bladder Cancer (KEYNOTE-866)
Study identification
- NCT ID
- NCT03924856
- Recruitment status
- Active, not recruiting
- Study type
- Interventional
- Phase
- Phase 3
- Lead sponsor
- Merck Sharp & Dohme LLC
- Industry
- Enrollment
- 907 participants
Conditions and interventions
Conditions
Interventions
- Cisplatin Drug
- Gemcitabine Drug
- Pembrolizumab Drug
- Placebo Drug
- Surgery (radical cystectomy (RC) plus Pelvic Lymph Node Dissection [PLND]) Procedure
Drug · Procedure
Eligibility (public fields only)
- Age range
- 18 Years and older
- Sex
- All
- Healthy volunteers
- Healthy volunteers not accepted
This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.
Study timeline
- Start date
- Jun 12, 2019
- Primary completion
- Jan 25, 2026
- Completion
- Aug 31, 2026
- Last update posted
- Aug 27, 2025
2019 – 2026
United States locations
- U.S. sites
- 24
- U.S. states
- 20
- U.S. cities
- 24
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| Scripps MD Anderson ( Site 0010) | La Jolla | California | 92037 | — |
| Providence Saint John's Health Center ( Site 0075) | Santa Monica | California | 90404 | — |
| Georgetown University Medical Center ( Site 0022) | Washington D.C. | District of Columbia | 20007 | — |
| AdventHealth Orlando-AdventHealth Medical Group Hematology & Oncology at Orlando ( Site 0005) | Orlando | Florida | 32804 | — |
| Parkview Cancer Institute ( Site 0077) | Fort Wayne | Indiana | 46845 | — |
| Indiana University Melvin and Bren Simon Cancer Center ( Site 0004) | Indianapolis | Indiana | 46202 | — |
| Ochsner Medical Center ( Site 0049) | New Orleans | Louisiana | 70121 | — |
| New England Cancer Specialists ( Site 0070) | Scarborough | Maine | 04074 | — |
| UMass Memorial Medical Center ( Site 0051) | Worcester | Massachusetts | 01655 | — |
| Henry Ford Hospital ( Site 0039) | Detroit | Michigan | 48202 | — |
| Mercy Hospital Saint Louis ( Site 0064) | St Louis | Missouri | 63141 | — |
| Morristown Medical Center ( Site 0015) | Morristown | New Jersey | 07960 | — |
| UNM Comprehensive Cancer Center-Clinical Research Office ( Site 0045) | Albuquerque | New Mexico | 87106 | — |
| New York University Perlmutter Cancer Center ( Site 0008) | New York | New York | 10016 | — |
| University Hospitals Cleveland Medical Center ( Site 0038) | Cleveland | Ohio | 44106 | — |
| Oklahoma Cancer Specialists and Research Institute, LLC ( Site 0021) | Tulsa | Oklahoma | 74146 | — |
| Portland VA Medical Center ( Site 0084) | Portland | Oregon | 97239 | — |
| Allegheny General Hospital ( Site 0048) | Pittsburgh | Pennsylvania | 15212 | — |
| MD Anderson Cancer Center ( Site 0063) | Houston | Texas | 77030 | — |
| Central Texas Veterans Healthcare System ( Site 0057) | Temple | Texas | 76504 | — |
| Inova Schar Cancer Institute ( Site 0007) | Fairfax | Virginia | 22031 | — |
| Northwest Medical Specialties, PLLC ( Site 0061) | Puyallup | Washington | 98373 | — |
| Seattle Cancer Care Alliance/Univ of Washington Medical Center ( Site 0033) | Seattle | Washington | 98109 | — |
| Charleston Area Medical Center ( Site 0023) | Charles Town | West Virginia | 25304 | — |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
Non-U.S. locations
This page focuses on the U.S. directory. The official record also lists 151 non-U.S. sites.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT03924856, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
- What this page does not do
- No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
- Where the data comes from
- Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
- Last refresh
- Last update posted Aug 27, 2025 · Synced May 12, 2026
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Open the official record
The complete protocol, eligibility criteria, and contact information for NCT03924856 live on ClinicalTrials.gov.