# 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)

> **NCT04634877** · PHASE3 · ACTIVE_NOT_RECRUITING · sponsor: **Merck Sharp & Dohme LLC** · enrollment: 990 (estimated)

## Conditions studied

- Endometrial Neoplasms

## Interventions

- **BIOLOGICAL:** Pembrolizumab
- **DRUG:** Carboplatin
- **DRUG:** Paclitaxel
- **DRUG:** Placebo for pembrolizumab
- **DRUG:** Docetaxel
- **DRUG:** Cisplatin
- **RADIATION:** External Beam Radiotherapy (EBRT)
- **DRUG:** Cisplatin (as radiosensitizer)
- **RADIATION:** Brachytherapy

## Key facts

- **NCT ID:** NCT04634877
- **Lead sponsor:** Merck Sharp & Dohme LLC
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE3
- **Study type:** INTERVENTIONAL
- **Status:** ACTIVE_NOT_RECRUITING
- **Start date:** 2021-01-10
- **Primary completion:** 2026-09-15
- **Final completion:** 2026-09-15
- **Target enrollment:** 990 (ESTIMATED)
- **Last updated:** 2025-06-09

## Collaborators

- [object Object]
- [object Object]

## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT04634877

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT04634877, "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)". Retrieved via AI Analytics 2026-06-02 from https://api.ai-analytics.org/clinical/NCT04634877. Licensed CC0.

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