JCO at ASCO Annual Meeting: Avelumab Plus Cetuximab vs. Avelumab in Advanced cSCC

JCO Editorial Fellow Dr. Ece Cali Daylan and JCO Associate Editor Dr. Grant McArthur discuss the ASCO 2025 Simultaneous Publication paper "A Phase II (Alliance A091802) Randomized Trial of Avelumab Plus Cetuximab vs. Avelumab Alone in Advanced Cutaneous Squamous Cell Carcinoma (cSCC)."

Transcript

The guest on this podcast episode has no disclosures to declare.

Dr. Ece Cali: Hello, and welcome to our 2025 ASCO Annual Meeting series where we cover some of the top JCO papers published simultaneously with their abstract presentation at this year's meeting. I'm your host, Dr. Ece Cali, and I'm joined by JCO Associate Editor Dr. Grant McArthur. Today, we will discuss Journal of Clinical Oncology article and abstract presentation "A Phase II Randomized Trial of Avelumab Plus Cetuximab Versus Avelumab Alone in Advanced Cutaneous Squamous Cell Carcinoma."

Let's start with a brief overview of the clinical trial. This is a randomized phase II trial that compared avelumab plus cetuximab to avelumab in PD-1/PD-L1 antibody-naive patients with advanced cutaneous squamous cell carcinoma. This is a cooperative group study conducted in the United States. Sixty patients were randomized one-to-one and stratified by PD-L1 and HIV status. The primary endpoint was progression-free survival. Patients on the cetuximab plus avelumab arm had a median PFS of 11.1 months, while patients on the avelumab arm had a median PFS of 3 months, corresponding to a hazard ratio of 0.48 with a p-value of 0.018. Grade III or higher treatment-related adverse events occurred in 48% of the patients on the combination arm versus 21% of patients on the avelumab arm.

Dr. McArthur, can you please explain to our listeners how you interpret this data?

Dr. Grant McArthur: These results are very important because they provide proof of concept for inhibiting PD-L1 as a target when combined with EGFR, so inhibiting PD-L1 with avelumab and inhibiting EGFR with cetuximab, in a randomized trial with a very significant impact in terms of efficacy. So, what this does is it provides proof of concept for inhibiting those targets in cutaneous squamous cell carcinoma of the skin. Avelumab is not approved for cutaneous squamous cell carcinoma of the skin, and so further studies would need to be done, particularly asking the question about combination with the approved PD-1 agents cemiplimab and pembrolizumab.

Dr. Ece Cali: I still find the difference in median PFS with various PD-1/PD-L1 inhibitors striking in this context. In this trial, avelumab, as you mentioned, the PD-L1 inhibitor, demonstrated a median PFS of 3 months, whereas PD-1 inhibitors cemiplimab and pembrolizumab have demonstrated longer median PFS in other trials.

So, what are some potential reasons for this, and do y