KEYNOTE-629: Use of Pembrolizumab in Treatment of Cutaneous Squamous Cell Carcinoma
Posted: Monday, October 11, 2021
The PD-1 inhibitor pembrolizumab may prove to be a safe and effective treatment option in locally advanced and recurrent or metastatic cutaneous squamous cell carcinomas. A study, conducted by Brett G.M. Hughes, MD, of the Royal Brisbane and Women’s Hospital and the Prince Charles Hospital, Australia, and colleagues, found that patients treated with pembrolizumab had improved objective response rates without unexpected adverse effects. Their findings were published in the Annals of Oncology.
“Pembrolizumab demonstrated robust, durable antitumor activity and promising survival in both locally advanced and recurrent or metastatic cutaneous squamous cell carcinoma,” said the investigators.
This multicenter phase II KEYNOTE-629 trial focused on 54 patients in the locally advanced cohort and 105 patients in the recurrent or metastatic cohort, with a median age of 74 years. All patients in the recurrent or metastatic cohort had received prior systemic therapy. Patients received pembrolizumab at 200 mg every 3 weeks for up to 35 infusions or approximately 2 years. Tumor status was evaluated every 6 weeks in year 1 and every 9 weeks in year 2.
Results showed an overall response rate of 50%, with a 16.7% complete response rate and a 33.3% partial response rate for the locally advanced cohort. The recurrent or metastatic cohort had an overall response rate of 35.2%, with a 10.5% complete response rate and a 24.8% partial response rate. The median progression-free survival was not met in the locally advanced group and was 5.7 months in the recurrent or metastatic group after a median 12-month follow-up.
Grade 3 or higher treatment-related adverse events were reported in 11.9% of patients. Treatment was discontinued in 14 participants as a result, and 2 treatment-related death were reported.
Study limitations included the small cohort size of patients with recurrent or metastatic disease who received first-line treatment with pembrolizumab, as well as the single-arm design of the study.
Disclosure: The study authors’ full disclosures can be found at annalsofoncology.org.