Immune-Based Drug, Pembrolizumab, Fights Advanced Endometrial Cancer: Study

Thursday, January 13, 2022 – A new clinical trial shows that a drug used to treat several types of cancer is also an effective treatment for aggressive forms of endometrial cancer, the second most common type of cancer in women worldwide. The endometrium is the inner lining of the uterus.

“These findings indicate a long-term benefit for patients,” said lead researcher Dr. David O’Malley, a gynecological oncologist at The Ohio State University Comprehensive Cancer Center in Columbus. “Even the possibility of a therapeutic intent is now possible in patients with recurrent or metastatic uterine cancer.”

Pembrolizumab, marketed as Keytruda, inhibits cellular receptors that prevent the immune system from recognizing and destroying cancer cells. It is already used to treat skin, lung, head/neck, cervical, and stomach cancers.

This mid-stage clinical trial involved 90 women in 15 countries with recurrent or advanced endometrial cancer. Their cancers were either MMR-deficient (dMMR) or MSI-high tumours, which means they were behaving abnormally.

According to the new report, 48% of advanced endometrial cancer patients experienced a complete or partial response to treatment. Response lasted in two-thirds over three years. Two-thirds of all patients in the study had a measurable response to treatment. The median follow-up was about 3.5 years – which means that half was followed for a shorter and half longer period.

The results are timely because endometrial cancer rates are on the rise. Cancer begins in the tissues lining the uterus. The study authors noted in a university news release that platinum-based chemotherapy drugs can be effective, but in many cases, the cancer returns.

According to the study team, effective treatments for cancer that has returned or has spread are limited. As a result, the five-year survival rate for women with advanced or recurrent endometrial cancer is 17%.

Up to 31% of endometrial cancer patients have DNA changes known as microsatellite instability (MSI-H) and mismatch repair deficiency (dMMR). O’Malley noted that the change is usually present in the tumor rather than a genetic mutation.

“By targeting this damaged pathway with this targeted drug, we can reset cellular mechanisms and allow the immune system to reactivate and attack cancer cells,” O’Malley said.

The authors note that prior to this study, there was no standard second-line care treatment for endometrial cancer patients with MSI-H/dMMR-positive tumors. They said the response to this treatment is generally very strong when compared to the expected 10% to 15% response rate for most second-line chemotherapy treatments.

The results were recently published online in Journal of Clinical Oncology.

Merck, which makes pembrolizumab, sponsored the study.


  • The Ohio State University Wexner Medical Center, press release, January 6, 2022

© 2022 HealthDay. All rights reserved.

Leave a Comment