Pembrolizumab or Placebo Plus Adjuvant Chemotherapy With or Without Radiotherapy for Newly Diagnosed, High-Risk Endometrial Cancer: Results in Mismatch Repair-Deficient Tumors

B Brian M. Slomovitz (Gynecologic Oncology, Mount Sinai Medical Center, Miami Beach, FL) D David Cibula W Weiguo Lv (Department of Gynecologic Oncology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China) F Fırat Ortaç (Ankara University School of Medicine, Ankara, Turkey) S Sakari Hietanen (Turku University Hospital and NSGO-CTU, Turku, Finland) F Floor Backes (The Ohio State University Comprehensive Cancer Center, Columbus, OH) A Akira Kikuchi D Domenica Lorusso (Gynecology Oncology Program Humanitas University San Pio X Milan Italy) A Anna Danska-Bidzinska V Vanessa Samouëlian (Gynecologic Oncology, Centre Hospitalier de l’Université de Montréal (CHUM), Centre de Recherche de l’Université de Montréal (CRCHUM), Université de Montréal, Montreal, QC, Canada) M Maria-Pilar Barretina-Ginesta (Grupo Español de Investigación en Cáncer de Ovario (GEICO) and Medical Oncology Department, Institut Català d´Oncologia (ICO), Girona, Spain) C Christof Vulsteke (Integrated Cancer Center Ghent, AZ Maria Middelares, Ghent, Belgium) C Chyong-Huey Lai (Gynecologic Cancer Research Center, Taoyuan City, Taiwan) B Bhavana Pothuri (Division of Gynecologic Oncology, Laura & Isaac Perlmutter Cancer Center, NYU Langone Health, New York, NY) Y Yu Zhang (Xiangya Hospital, Central South University Changsha China) M Manuel Magallanes-Maciel (Centro Oncologico Internacional, Mexico City, Mexico) A Amnon Amit (Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel) V Valentina Guarneri (Veneto Institute of Oncology, Istituto di Ricovero e Cura a Carattere Scientifico, Padua, Italy) F Flora Zagouri (Alexandra Hospital, Athens, Greece) M Maria Bell J Julia Welz G Gemma Eminowicz M Martin Hruda (Central and Eastern European Gynecologic Oncology Group (CEEGOG), Prague, Czech Republic) L Lyndsay J. Willmott (GOG Foundation, Philadelphia, PA) J Jasmine Lichfield (Astellas Pharma Europe Ltd, Addlestone, United Kingdom) W Wei Wang R Robert Orlowski (University of Texas M.D. Anderson Cancer Center, Houston) G Gursel Aktan (Merck & Co, Inc, Rahway, NJ) L Laurence Gladieff T Toon Van Gorp

Abstract

Mismatch repair-deficient (dMMR) endometrial cancer (EC) is an inflamed phenotype with poor outcomes when meeting high-risk criteria and limited treatment options in the adjuvant setting. We report protocol-prespecified subgroup analysis of patients with dMMR tumors from the phase III ENGOT-en11/GOG-3053/KEYNOTE-B21 study (ClinicalTrials.gov identifier: NCT04634877 ) in newly diagnosed, high-risk EC after surgery with curative intent. Patients were randomly assigned to pembrolizumab 200 mg or placebo (six cycles) plus carboplatin-paclitaxel (four to six cycles) once every 3 weeks, then pembrolizumab 400 mg or placebo once every 6 weeks (six cycles), respectively. MMR status was a stratification factor. Patients received radiotherapy at investigator discretion. Investigator-assessed disease-free survival (DFS) was a primary end point. No formal hypothesis testing was performed for subgroup analysis. In the intention-to-treat population, 141 patients in the pembrolizumab arm and 140 in the placebo arm had dMMR tumors. At this interim analysis, hazard ratio for DFS favored pembrolizumab (0.31 [95% CI, 0.14 to 0.69]); median DFS was not reached in either group. Two-year DFS rates were 92.4% (95% CI, 84.4 to 96.4) and 80.2% (95% CI, 70.8 to 86.9), respectively. No new safety signals occurred. Longer-term follow-up of outcomes will be evaluated at final analysis. Preplanned subgroup analysis on the basis of the study's stratification factors suggests that pembrolizumab plus chemotherapy improves DFS and is clinically relevant for patients with dMMR tumors in the curative-intent setting.

Article Details

Volume / Issue Vol. 43, Issue 3
Published January 20, 2025
Pages 251-259
ISSN 0732-183X
Publisher Lippincott Williams & Wilkins

Journal Info

Journal of Clinical Oncology

Lippincott Williams & Wilkins

ISSN: 0732-183X Health Sciences

Authors (30)

B

Brian M. Slomovitz

Gynecologic Oncology, Mount Sinai Medical Center, Miami Beach, FL

D

David Cibula

W

Weiguo Lv

Department of Gynecologic Oncology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China

F

Fırat Ortaç

Ankara University School of Medicine, Ankara, Turkey

S

Sakari Hietanen

Turku University Hospital and NSGO-CTU, Turku, Finland

F

Floor Backes

The Ohio State University Comprehensive Cancer Center, Columbus, OH

A

Akira Kikuchi

D

Domenica Lorusso

Gynecology Oncology Program Humanitas University San Pio X Milan Italy

A

Anna Danska-Bidzinska

V

Vanessa Samouëlian

Gynecologic Oncology, Centre Hospitalier de l’Université de Montréal (CHUM), Centre de Recherche de l’Université de Montréal (CRCHUM), Université de Montréal, Montreal, QC, Canada

M

Maria-Pilar Barretina-Ginesta

Grupo Español de Investigación en Cáncer de Ovario (GEICO) and Medical Oncology Department, Institut Català d´Oncologia (ICO), Girona, Spain

C

Christof Vulsteke

Integrated Cancer Center Ghent, AZ Maria Middelares, Ghent, Belgium

C

Chyong-Huey Lai

Gynecologic Cancer Research Center, Taoyuan City, Taiwan

B

Bhavana Pothuri

Division of Gynecologic Oncology, Laura & Isaac Perlmutter Cancer Center, NYU Langone Health, New York, NY

Y

Yu Zhang

Xiangya Hospital, Central South University Changsha China

M

Manuel Magallanes-Maciel

Centro Oncologico Internacional, Mexico City, Mexico

A

Amnon Amit

Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel

V

Valentina Guarneri

Veneto Institute of Oncology, Istituto di Ricovero e Cura a Carattere Scientifico, Padua, Italy

F

Flora Zagouri

Alexandra Hospital, Athens, Greece

M

Maria Bell

J

Julia Welz

G

Gemma Eminowicz

M

Martin Hruda

Central and Eastern European Gynecologic Oncology Group (CEEGOG), Prague, Czech Republic

L

Lyndsay J. Willmott

GOG Foundation, Philadelphia, PA

J

Jasmine Lichfield

Astellas Pharma Europe Ltd, Addlestone, United Kingdom

W

Wei Wang

R

Robert Orlowski

University of Texas M.D. Anderson Cancer Center, Houston

G

Gursel Aktan

Merck & Co, Inc, Rahway, NJ

L

Laurence Gladieff

T

Toon Van Gorp