Study of Pembrolizumab (MK-3475) in Combination With Adjuvant Chemotherapy With or Without Radiotherapy in Participants With Newly Diagnosed Endometrial Cancer After Surgery With Curative Intent (MK-3475-B21 / KEYNOTE-B21 / ENGOT-en11 / GOG-3053)
Public ClinicalTrials.gov record NCT04634877. 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 of Pembrolizumab Versus Placebo in Combination With Adjuvant Chemotherapy With or Without Radiotherapy for the Treatment of Newly Diagnosed High-Risk Endometrial Cancer After Surgery With Curative Intent (KEYNOTE-B21 / ENGOT-en11 / GOG-3053)
Study identification
- NCT ID
- NCT04634877
- Recruitment status
- Active, not recruiting
- Study type
- Interventional
- Phase
- Phase 3
- Lead sponsor
- Merck Sharp & Dohme LLC
- Industry
- Enrollment
- 990 participants
Conditions and interventions
Conditions
Interventions
- Pembrolizumab Biological
- Carboplatin Drug
- Paclitaxel Drug
- Placebo for pembrolizumab Drug
- Docetaxel Drug
- Cisplatin Drug
- External Beam Radiotherapy (EBRT) Radiation
- Cisplatin (as radiosensitizer) Drug
- Brachytherapy Radiation
Biological · Drug · Radiation
Eligibility (public fields only)
- Age range
- 18 Years and older
- Sex
- Female
- 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
- Jan 9, 2021
- Primary completion
- Sep 14, 2026
- Completion
- Sep 14, 2026
- Last update posted
- Jun 4, 2026
2021 – 2026
United States locations
- U.S. sites
- 29
- U.S. states
- 22
- U.S. cities
- 29
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| University of Alabama - Birmingham ( Site 3061) | Birmingham | Alabama | 35249 | — |
| University of South Alabama, Mitchell Cancer Institute ( Site 3058) | Mobile | Alabama | 36604 | — |
| HonorHealth Research Institute - Biltmore ( Site 3043) | Phoenix | Arizona | 85016 | — |
| Arizona Oncology Associates PC- HOPE ( Site 3049) | Tucson | Arizona | 85711 | — |
| UCSD Moores Cancer Center ( Site 3053) | La Jolla | California | 92093-0698 | — |
| University Of Colorado ( Site 3051) | Aurora | Colorado | 80045 | — |
| Smilow Cancer Hospital at Yale New Haven ( Site 3070) | New Haven | Connecticut | 06511 | — |
| Mount Sinai Cancer Center ( Site 3081) | Miami Beach | Florida | 33140 | — |
| Northside Hospital ( Site 3036) | Atlanta | Georgia | 30342 | — |
| Northwestern Memorial Hospital ( Site 3044) | Chicago | Illinois | 60611 | — |
| Parkview Cancer Institute ( Site 3067) | Fort Wayne | Indiana | 46845 | — |
| Indiana University Melvin and Bren Simon Cancer Center ( Site 3071) | Indianapolis | Indiana | 46202 | — |
| University of Iowa Hospital and Clinics ( Site 3046) | Iowa City | Iowa | 52242 | — |
| Norton Cancer Institute - St. Matthews ( Site 3056) | Louisville | Kentucky | 40207 | — |
| WK Physicians Network/Gynecologic Oncology Associates ( Site 3047) | Shreveport | Louisiana | 71103 | — |
| University of Massachusetts Medical School-Division of Gynecologic Oncology ( Site 3037) | Worcester | Massachusetts | 01605 | — |
| Perlmutter Cancer Center at NYU Langone Hospital - Long Island ( Site 3076) | Mineola | New York | 11501 | — |
| Laura and Isaac Perlmutter Cancer Center at NYU Langone Health ( Site 3042) | New York | New York | 10016 | — |
| Montefiore Medical Center ( Site 3065) | The Bronx | New York | 10461 | — |
| Duke Cancer Center ( Site 3072) | Durham | North Carolina | 27710 | — |
| Sanford Fargo Medical Center-Roger Maris Cancer Center ( Site 3080) | Fargo | North Dakota | 58102 | — |
| The James Cancer Hospital and Solove Research Institute at The Ohio State University Comprehensive C ( Site 3066) | Columbus | Ohio | 43210 | — |
| Legacy Good Samaritan Medical Center ( Site 3033) | Portland | Oregon | 97210 | — |
| Sidney Kimmel Cancer Center - Jefferson Health ( Site 3078) | Philadelphia | Pennsylvania | 19107 | — |
| AHN West Penn Hospital ( Site 3060) | Pittsburgh | Pennsylvania | 15224 | — |
| Abington Hospital - Asplundh Cancer Center ( Site 3073) | Willow Grove | Pennsylvania | 19090 | — |
| Sanford Gynecology Oncology ( Site 3045) | Sioux Falls | South Dakota | 57104 | — |
| UT Southwestern Medical Center ( Site 3063) | Dallas | Texas | 75390 | — |
| VCU Massey Cancer Center ( Site 3068) | Richmond | Virginia | 23298 | — |
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 202 non-U.S. sites.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT04634877, 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 Jun 4, 2026 · Synced Jul 23, 2026
Related: full search, browse by condition, browse by drug or therapy, browse by sponsor, browse by U.S. city.
Open the official record
The complete protocol, eligibility criteria, and contact information for NCT04634877 live on ClinicalTrials.gov.