C-POST Trial Shows Adjuvant Cemiplimab Cuts Risk in High-Risk Skin Cancer
The C-POST trial shows adjuvant cemiplimab improves disease-free survival in high-risk cutaneous squamous cell carcinoma, with a hazard ratio of 0.32. Meanwhile, an international Phase III study is testing cemiplimab before surgery in advanced cases. Cemiplimab is FDA-approved for advanced skin cancer but not yet for pre-surgical use.
The first randomized trial of adjuvant immunotherapy with cemiplimab in patients with resected high-risk cutaneous squamous cell carcinoma (cSCC) has demonstrated a significant improvement in disease-free survival. In the C-POST trial, 415 participants were assigned to receive either cemiplimab or placebo for up to 48 weeks, with a median follow-up of 24 months. The hazard ratio for recurrence or death was 0.32, indicating a 68% reduction in risk.
Cemiplimab targets programmed death 1 (PD-1) and has been approved by the FDA for the treatment of skin cancer that has spread or that cannot be removed by surgery, but it has not yet been approved for the treatment of skin cancer before surgery. Cutaneous squamous cell carcinoma is a localized disease that can be cured surgically in most patients; however, about 5% develop nodal or distant metastases. It affects more than a million Americans each year.
An international Phase III clinical trial is now evaluating whether adding cemiplimab before surgery results in better outcomes than the current standard of care. The study aims to enroll an estimated 420 patients across more than 170 sites worldwide. Eligible participants are adults 18 or older with previously untreated or recurrent squamous cell skin cancer who are candidates for surgical resection. Previous studies have shown a positive response to this treatment approach.