Pivotal Phase 3 Data for KEYTRUDA in High-Risk Early-Stage Triple-Negative Breast Cancer

  Merck & Co. (NYSE: MRK), known as MSD outside the United States and Canada, today announced the publication of results from the Phase 3 KEYNOTE-522 trial in the Feb. 10, 2022 edition of the New England Journal of Medicine. Results showed that neoadjuvant KEYTRUDA, Merck’s anti-PD-1 therapy, in combination with chemotherapy followed by adjuvant KEYTRUDA as monotherapy (the KEYTRUDA regimen), significantly prolonged event-free survival (EFS) compared with neoadjuvant chemotherapy followed by adjuvant placebo (the chemotherapy-placebo regimen) in patients with high-risk early-stage triple-negative breast cancer (TNBC).

As previously reported, after a median follow-up of 39 months, the KEYTRUDA regimen reduced the risk of events or death by 37% (HR=0.63 [95% CI, 0.48-0.82]; p<0.001) versus the chemotherapy-placebo regimen. A total of 15.7% (n= 123/784) of patients who received the KEYTRUDA regimen had an EFS event compared to 23.8% (n= 93/390) of patients who received the chemotherapy-placebo regimen. The estimated three-year EFS rates were 84.5% (95% CI, 81.7-86.9) in the KEYTRUDA group compared with 76.8% (95% CI, 72.2-80.7) in the chemotherapy-placebo group. Event-free survival was defined as the time from randomization to the first occurrence of either disease progression that precluded definitive surgery, a local/distant recurrence, a second primary malignancy, or death from any cause. The safety profile of the KEYTRUDA regimen was consistent with the known profiles of each regimen, and no new safety concerns were identified. Additional detailed efficacy and safety data are also featured in the publication.

KEYTRUDA in combination with chemotherapy as neoadjuvant treatment and then continued as a single agent as adjuvant treatment after surgery is approved in the U.S. for the treatment of patients with high-risk early-stage TNBC. Additional global regulatory submissions are ongoing.

“These data, which supported the FDA approval and updates to the NCCN guidelines, establish that KEYTRUDA plus chemotherapy as neoadjuvant therapy followed by adjuvant KEYTRUDA could change clinical practice for the treatment of patients with high-risk early-stage TNBC,” said Dr. Peter Schmid, lead, Centre for Experimental Cancer Medicine, Barts Cancer Institute in London, England. “KEYNOTE-522 is the first prospective randomized Phase 3 trial to show an improvement in event-free survival among patients with stage II and stage III TNBC.”

https://www.biospace.com/article/releases/pivotal-phase-3-data-for-keytruda-pembrolizumab-in-high-risk-early-stage-triple-negative-breast-cancer-tnbc-published-in-the-new-england-journal-of-medicine/