Posted: Friday, June 10, 2022
Paolo Bossi, MD, of the University of Brescia, Italy, and colleagues observed that the addition of cetuximab to pembrolizumab tended to revert primary and acquired resistance in the treatment of patients with locally advanced or metastatic cutaneous squamous cell carcinoma. The I-TACKLE phase II study findings were presented at the 2022 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 9520).
“The sequential approach deserves to be studied in future clinical trials,” concluded the study investigators.
The study recruited patients from three Italian centers; eligible patients had locally advanced or metastatic cutaneous squamous cell carcinoma that was not managed with surgery or radiation therapy. In cases of a partial or complete response, patients received pembrolizumab alone. In the event of disease stability or disease progression, patients received cetuximab and pembrolizumab.
A total of 43 patients were enrolled in the study and treated with pembrolizumab between May 2019 and April 2021. Of this population, 34 patients were male, and the median age was 79 years. The median follow-up time was 24 months.
Further, 23 patients underwent the combination treatment, 21 of whom experienced primary resistance and 2 of whom experienced acquired resistance. Of the 23 patients, 10 responded to the combination therapy. The median treatment duration was 3 months for pembrolizumab and 4 months for the combination therapy. The cumulative objective response rate was 63%, including 44% who responded to pembrolizumab and 38% who responded to the combination therapy. The median duration of response and overall survival were not reached with pembrolizumab alone and with pembrolizumab plus cetuximab. The 1-year progression-free survival was 51% with pembrolizumab alone and 42% with pembrolizumab plus cetuximab.
Overall, grade 3 or 4 treatment-related adverse events occurred in 16% of patients during treatment with pembrolizumab and in 35% of patients during treatment with pembrolizumab and cetuximab. With the combination treatment, 30% of patients experienced dermatitis. Four patients died during treatment due to disease progression.
Disclosure: For full disclosures of the study authors, visit coi.asco.org