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)

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)

• Status: Active Not Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 990 (estimated)
• Sponsor: Merck Sharp & Dohme LLC · Industry
• Sex: Female
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The purpose of this study is to compare pembrolizumab + adjuvant chemotherapy with placebo + adjuvant chemotherapy, with or without radiotherapy, with respect to disease-free survival (DFS) as assessed radiographically by the investigator or by histopathologic confirmation of suspected disease recurrence, and with respect to overall survival (OS). The primary hypotheses are that pembrolizumab + adjuvant chemotherapy is superior to placebo + adjuvant chemotherapy, with or without radiotherapy, with respect to DFS as assessed radiographically by the investigator or by histopathologic confirmation of suspected disease recurrence, and with respect to OS.

Conditions

• Endometrial Neoplasms

Interventions

Type	Name	Description
BIOLOGICAL	Pembrolizumab	IV infusion
DRUG	Carboplatin	IV infusion
DRUG	Paclitaxel	IV infusion
DRUG	Placebo for pembrolizumab	IV infusion
DRUG	Docetaxel	IV infusion docetaxel 75 mg/m\^2 Q3W or 25 mg/m2 QW may be given in place of paclitaxel following sponsor consultation if a participant experiences severe hypersensitivity to paclitaxel or an adverse event requiring discontinuation of paclitaxel.
DRUG	Cisplatin	Cisplatin 75 mg/m\^2 IV infusion Q3W may be given in place of carboplatin following sponsor consultation if a participant experiences severe hypersensitivity to carboplatin or an adverse event requiring discontinuation of carboplatin.
RADIATION	External Beam Radiotherapy (EBRT)	≥4500 cGY given according to local practice, at the discretion of the investigator
DRUG	Cisplatin (as radiosensitizer)	If a participant receives external beam radiotherapy (EBRT), then cisplatin 50 mg/m\^2 IV infusion may be administered as a radiosensitizer at the discretion of the investigator, on days 1 and 29
RADIATION	Brachytherapy	Given according to local practice, at the discretion of the investigator

Timeline

• Start date: 2021-01-10
• Primary completion: 2026-09-15
• Completion: 2026-09-15
• First posted: 2020-11-18
• Last updated: 2025-06-09

Locations

231 sites across 28 countries: United States, Argentina, Austria, Belgium, Canada, Chile, China, Colombia, Czechia, Denmark, Finland, France, Germany, Greece, Israel, Italy, Japan, Mexico, Norway, Poland, Russia, South Korea, Spain, Sweden, Taiwan, Turkey (Türkiye), Ukraine, United Kingdom

Regulatory

• FDA-regulated drug study