Nurse Takeaways: Latest Pembrolizumab Indication in Endometrial Cancer

Courtney Arn, APRN-CNP, a nurse practitioner in the Division of Gynecologic Oncology, The Ohio State University Wexner Medical Center and The James Comprehensive Cancer Center, discusses the recent FDA approval of pembrolizumab (Keytruda) for patients with microsatellite instability–high (MSI-H)/mismatch repair deficient (dMMR) advanced endometrial carcinoma.

On March 21, 2022, the FDA approved pembrolizumab monotherapy to treat patients with MSI-H or dMMR advanced endometrial carcinoma. This approval provides patients with an effective treatment option with manageable toxicity, according to Arn.

The decision is based off findings from cohorts D and K of the KEYNOTE-158 trial (NCT02628067). Findings showed that the objective response rate (ORR) was 46% (95% CI, 35%-56%) among patients who received pembrolizumab. Furthermore, at a median follow-up of 16.0 months (range, 0.5-62.1), the complete response (CR) rate among this population was 12% and the partial response rate was 33%.

Among patients who responded to treatment, 68% reported responses lasting 12 months or longer, and 44% reported responses lasting 24 months or longer. No median duration of response (DOR) was reached (range, 2.9-55.7 months).

In terms of safety, the drug has demonstrated promising toxicity levels, according to Arn. It is also a straightforward drug to administer to patients, she added.

“[There is a] very low risk of [developing] a hypersensitivity reaction to pembrolizumab, but there is a possibility of having a hypersensitivity infusion–related reaction,” said Arn. “These are a little bit different than with typical chemotherapy; they sometimes can become hypotensive, tachycardic, or have a fever. This hypersensitivity is usually managed with IV fluids, antipyretic, or antihistamines to help stop the reaction.”

“If it is a mild reaction, they can restart the infusion,” she continued. “However, it might be in a patient's best interest to give pre-medications or give the infusion over a slower rate if they do have an infusion-related reaction.”