Pembrolizumab as first line therapy in patients with unresectable squamous cell carcinoma of the skin: Interim results of the phase 2 CARSKIN trial.

International audienc

Etude de phase II de l’administration de Pembrolizumab en monothérapie et en première ligne chez des patients présentant un carcinome épidermoïde cutané inopérable.

International audienc

Phase II Study of Pembrolizumab As First-Line, Single-Drug Therapy for Patients With Unresectable Cutaneous Squamous Cell Carcinomas

International audiencePURPOSE To evaluate first-line pembrolizumab monotherapy efficacy and safety in patients with unresectable cutaneous squamous cell carcinomas (CSCCs). PATIENTS AND METHODS Patients, predominantly men, with their CSSCs’ immunohistochemically determined programmed cell death-ligand 1 (PD-L1) status determined (tumor proportion score threshold, 1%), received pembrolizumab (200 mg every 3 weeks). The primary endpoint was the 39-patient primary cohort’s objective response rate at week 15 (ORR W15 ). Secondary objectives were best ORR, overall survival (OS), progression-free survival (PFS), duration of response (DOR), safety, ORR according to PD-L1 status and health-related quality of life using Functional Assessment of Cancer Therapy–General (FACT-G) score. An 18-patient expansion cohort, recruited to power the study to evaluate the ORR W15 difference between PD-L1+ and PD-L1– patients, was assessed for ORR, disease control rate, and safety, but not survival. RESULTS Median age of all patients was 79 years. The primary cohort’s ORR W15 was 41% (95% CI, 26% to 58%), including 13 partial and 3 complete responses. Best responses were 8 partial and 8 complete responses. At a median follow-up of 22.4 months, respective median PFS, DOR, and OS were 6.7 months, not reached, and 25.3 months, respectively. Pembrolizumab-related adverse events affected 71% of the patients, and 4 (7%) were grade ≥ 3. One death was related to rapid CSCC progression; another resulted from a fatal second aggressive head and neck squamous cell carcinoma diagnosed 15 weeks postinclusion. ORR W15 for the entire population was 42%; it was significantly higher for PD-L1+ patients (55%) versus PD-L1– patients (17%; P = .02). Responders’ W15 total FACT-G score had improved ( P = .025) compared with nonresponders. CONCLUSION First-line pembrolizumab monotherapy exhibited promising anti-CSCC activity, with durable responses and manageable safety. PD-L1 positivity appears to be predictive of pembrolizumab efficacy