Phase III Trial Investigating Adjuvant Cemiplimab in High-Risk CSCC

Mitchell Smith, MD, PhD

Mitchell Smith, MD, PhD

A phase III clinical trial has begun to investigate the use of cemiplimab (Libtayo) as an adjuvant treatment after surgery and radiation therapy in patients with high-risk cutaneous squamous cell carcinoma (NCT03969004).

Following theFDA approval for cemiplimab in September 2018for the treatment of patients with metastatic cutaneous squamous cell carcinoma or patients with locally advanced disease who are not candidates for curative surgery or radiation, the PD-1 inhibitor is being investigated in additional settings to improve outcomes for patients with cutaneous malignancies. The approval for cemiplimab marked the first treatment available for patients with advanced cutaneous squamous cell carcinoma.

“By combining innovative immunotherapies with standard treatments, like surgery and radiation, we are hoping to see improved outcomes for patients with cutaneous squamous cell carcinoma,” said Mitchell Smith, MD, PhD, associate center director for clinical investigations at the George Washington University (GW) Cancer Center, in a statement. “By conducting this trial, we hope to understand whether this approach can help the patient's own immune system control the skin cancer and keep it from coming back.”

Cutaneous squamous cell carcinoma is the second most common form of skin cancer, accounting for about 20% of all non-melanoma skin cancer cases.

The randomized, placebo-controlled, double-blind study is expecting to enroll about 412 patients with high-risk cutaneous squamous cell carcinoma and compare the use of adjuvant cemiplimab with placebo. Both the immune checkpoint inhibitor and placebo will be administered as an intravenous infusion over 30 minutes.

Patients in the trial must be 21 years or older; have an ECOG performance status of 0 or 1; have adequate hepatic, renal, and bone marrow function, and must have completed curative intent post-operative radiation within 2 to 6 weeks of randomization. Those with non-cutaneous squamous cell carcinomas, other malignancies (concurrent or within 3 years), or significant autoimmune disease (concurrent or within 5 years) that requires the use of systemic immunosuppressive treatment were excluded from the trial.

The primary endpoint of the trial is disease-free survival, which is defined in the trial as the time from randomization to the first documented disease recurrence or death of any cause. Secondary endpoints include overall survival, freedom from distant and locoregional recurrence after surgery and radiation, cumulative incidence of second primary cutaneous squamous cell carcinoma tumors, and safety.

The GW Cancer Center, through their Cutaneous Oncology Program, was selected as the first global site for the clinical trial. Vishal A. Patel, MD, director of the Cutaneous Oncology Program, will be the lead investigator of the trial.

“Our participation in this trial represents an important achievement for the GW Cancer Center. Being selected as the first site for this study solidifies our increasing reputation as innovators in clinical research and demonstrates our ongoing commitment to investigating potentially promising therapies for patients,” said Eduardo M. Sotomayor, MD, the Dr Cyrus Katzen Family Director of the GW Cancer Center and professor of medicine at the GW School of Medicine and Health Sciences, in a statement.