Adjuvant Libtayo® (cemiplimab) Significantly Improves Disease-Free Survival (DFS) After Surgery in High-Risk Cutaneous Squamous Cell Carcinoma (CSCC) in Phase 3 Trial

Primary endpoint of DFS met at first prespecified interim analysis, showing a 68% reduction in the risk of disease recurrence or death in patients with high-risk CSCC after surgery compared to placebo

Libtayo is the first and only immunotherapy to show a statistically significant and clinically meaningful benefit in high-risk CSCC in the adjuvant setting; a recent Phase 3 trial with Keytruda® failed in the same setting1  Libtayo is standard of care for certain patients with advanced CSCC

TARRYTOWN, N.Y., Jan. 13, 2025 (GLOBE NEWSWIRE) -- Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) today announced positive results from the Phase 3 C-POST trial, which demonstrated that adjuvant treatment with PD-1 inhibitor Libtayo® (cemiplimab) led to a statistically significant and clinically meaningful improvement in the primary endpoint of disease-free survival (DFS) in patients with high-risk cutaneous squamous cell carcinoma (CSCC) after surgery.

“While surgery is curative for most people living with cutaneous squamous cell carcinoma, many are burdened with a higher risk of recurrence that can lead to death or disfiguration,” said Danny Rischin, M.D., M.B.B.S., F.R.A.C.P., Research Lead, Head and Neck Cancer and Cutaneous SCC, Department of Medical Oncology at the Peter MacCallum Cancer Centre in Melbourne, Australia, and lead investigator of the trial. “At the first prespecified interim analysis, Libtayo achieved a remarkably high bar in improving disease-free survival in high-risk cutaneous squamous cell carcinoma. With no currently approved options in the adjuvant setting, these landmark results demonstrate Libtayo could represent a major advance in delaying recurrence in these vulnerable patients.”

C-POST enrolled 415 patients with high-risk CSCC who were randomized to receive either Libtayo or placebo for up to 48 weeks. The primary endpoint was DFS, defined as time from randomization to the first documented disease recurrence or death due to any cause. At the first prespecified interim analysis for DFS with a median duration of follow-up of 24 months (range: 2-64 months), Libtayo demonstrated a 68% reduction in the risk of disease recurrence or death, compared to placebo (hazard ratio: 0.32; 95% confidence interval: 0.20-0.51; p