Mount Sinai Medical Center Physician Leads Global Phase 3 Trial Showing Chemotherapy-Free Treatment Improves Outcomes for Women with dMMR Endometrial Cancer

KEYNOTE-C93/GOG-3064/ENGOT-en15 results presented in the ESMO 2026 Presidential Symposium and published simultaneously in The Lancet

MIAMI BEACH, Fla., Oct. 26, 2026 /PRNewswire/ -- Women with advanced or recurrent mismatch repair deficient (dMMR) endometrial cancer who were treated with immunotherapy alone lived longer without their cancer progressing than women treated with chemotherapy, according to results of the global Phase 3 KEYNOTE-C93/GOG-3064/ENGOT-en15 trial presented today at the European Society for Medical Oncology (ESMO) Congress 2026 in Madrid. The trial was led by Brian Slomovitz, MD, Director of Gynecologic Oncology and Deputy Director of the Braman Comprehensive Cancer Center at Mount Sinai Medical Center, who served as global principal investigator on behalf of the GOG Foundation. The findings were published simultaneously in The Lancet.

The randomized trial enrolled 299 patients and compared pembrolizumab (KEYTRUDA®), Merck's anti-PD-1 therapy, with carboplatin and paclitaxel chemotherapy as first-line treatment, the first therapy patients receive for advanced or recurrent disease. Pembrolizumab reduced the risk of disease progression or death by 43% compared with chemotherapy (hazard ratio 0.57). Overall survival data are still maturing, and follow-up continues. Patients treated with pembrolizumab also reported improved quality of life, with no new safety signals.

Women treated at the Braman Comprehensive Cancer Center were among the trial's participants.

Endometrial cancer is the most common gynecologic cancer in the United States and one of the few cancers with rising incidence and mortality, according to the American Cancer Society. dMMR tumors make up about 30% of endometrial cancers and are the subtype most responsive to immunotherapy. Pembrolizumab is already part of an established frontline treatment regimen with platinum doublet chemotherapy for patients with primary advanced or recurrent endometrial cancer regardless of mismatch repair status. KEYNOTE-C93 asked whether, for women with dMMR tumors, chemotherapy could be removed entirely.

"These results highlight the potential of a chemotherapy-free approach for certain patients with dMMR advanced or recurrent endometrial cancer, with pembrolizumab monotherapy demonstrating a clinically meaningful benefit in progression-free survival along with a favorable quality of life compared to chemotherapy," said Dr. Slomovitz. "After years of platinum-based chemotherapy serving as the frontline standard, these findings could help provide an additional treatment option beyond carboplatin plus paclitaxel in combination with KEYTRUDA for these patients."

Dr. Slomovitz serves on the Board of Directors of the GOG Foundation and is Uterine Cancer Lead for GOG Partners. He has served as national or global principal investigator on multiple GOG Partners, National Cancer Institute and Alliance Foundation trials.

KEYNOTE-C93 was one of 12 studies selected from across the congress for presentation in the ESMO 2026 Presidential Symposia.

"When oncologists from around the world gathered to hear what's next in women's cancer care, they heard it from one of our own," said Gino R. Santorio, President and Chief Executive Officer of Mount Sinai Medical Center. "Dr. Slomovitz's leadership means the women in our community have access to the research shaping cancer care everywhere, close to home."

Dr. Slomovitz is available for interviews in Madrid and upon his return.

For more information, please visit https://www.msmc.com/comprehensive-cancer-center.

KEYTRUDA® is a registered trademark of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.

About Keynote C93 (GOG-3064/ENGOT-en15)
KEYNOTE-C93 (GOG-3064/ENGOT-en15) is a global, randomized Phase 3 trial sponsored by Merck comparing pembrolizumab with chemotherapy in women with advanced or recurrent dMMR endometrial cancer. The results were published in The Lancet.

About Mount Sinai Medical Center
Founded in 1949, Mount Sinai Medical Center is the largest independent, private, not-for-profit teaching hospital in South Florida. Mount Sinai's mission is to provide quality health care to a diverse community enhanced through teaching, research, charity care, and financial responsibility. Mount Sinai's Centers of Excellence combine technology, research, and academics to provide innovative and comprehensive care in cardiology, neuroscience, oncology, urology, and orthopedics. One of the original statutory teaching hospitals in the state of Florida, Mount Sinai is the hospital of choice for those who seek the level of expertise and care that only a teaching hospital can offer. Mount Sinai currently offers ten convenient locations in Miami-Dade County, including four emergency centers, and five specialty care offices in Monroe County. 

SOURCE Mount Sinai Medical Center