Abstract 1062P
Background
Cutaneous squamous cell carcinoma (CSCC) is the second most common cutaneous malignancy and patients with locally advanced or metastatic disease have a poor prognosis. Cemiplimab, a monoclonal anti-PD-1 antibody, has recently been approved by the FDA and EMA for this patient cohort based on single-arm phase II studies. Real-world data on clinical outcome and tolerability is still scarce.
Methods
In this retrospective cohort analysis, patients treated with cemiplimab for advanced CSCC from 3 sites in the Netherlands from November 2018 until August 2020 were evaluated for response and toxicity. Collected data comprised patient’s demographics, tumor characteristics and treatment course. Clinical response, adverse events (AE), progression-free survival (PFS) and overall survival (OS) were assessed.
Results
In total, 66 patients (50 male, 16 female, median age 75; range 30-93 years) with unresectable locoregional (41 (62%) patients) or metastatic (25 (38%) patients) CSCC treated with flatdose cemiplimab 350mg Q3W were included. All but 8 patients (88%) had severe comorbidities, the most common site of the primary tumor was the head or neck (79%) and 7 (11%) patients were pretreated with systemic therapy. A median of 6.5 doses of cemiplimab (range 1-31 doses) were administered and treatment was well-tolerated, with grade 1-2 AEs in 70% and grade 3-4 AEs in 17% of patients. An objective clinical response was seen in 33 (50%) patients, of whom 9 (14%) reached CR and 24 (36%) PR. With a median follow-up of 11.7 months (95% CI 8.4-15.0 months), median PFS was 17.3 months and median OS was not reached. In 39 (59%) patients treatment was discontinued, mostly due to disease progression (49%). In 8 (21%) patients with ongoing response treatment was stopped after a median of 11.5 months (range 2.9-15.2 months).
Conclusions
In this real-world cohort of advanced CSCC patients, cemiplimab demonstrated to be well-tolerated, achieving an objective clinical response in 50% of patients, even in elderly patients with severe comorbidities. Their outcome was comparable to the results of prospective clinical trials.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
L.A. Devriese: Non-Financial Interests, Institutional, Advisory Role: BMS; Non-Financial Interests, Institutional, Advisory Role: Merck; Non-Financial Interests, Institutional, Advisory Role: MSD. J.B.A.G. Haanen: Non-Financial Interests, Institutional, Advisory Role: Achilles Therapeutics; Non-Financial Interests, Institutional, Advisory Role: Aimm; Non-Financial Interests, Institutional, Advisory Role: BioNTech; Non-Financial Interests, Institutional, Advisory Role: BMS; Non-Financial Interests, Institutional, Advisory Role: Gadeta; Non-Financial Interests, Institutional, Advisory Role: Immunocore; Non-Financial Interests, Institutional, Advisory Role: Ipsen; Non-Financial Interests, Institutional, Advisory Role: MSD; Non-Financial Interests, Institutional, Advisory Role: Merck Serono; Non-Financial Interests, Institutional, Advisory Role: Molecular Partners; Non-Financial Interests, Institutional, Advisory Role: Neogene Therapeutics; Non-Financial Interests, Institutional, Advisory Role: Novartis; Non-Financial Interests, Institutional, Advisory Role: Pfizer; Non-Financial Interests, Institutional, Advisory Role: Roche/Genentech; Non-Financial Interests, Institutional, Advisory Role: Sanofi; Non-Financial Interests, Institutional, Advisory Role: Seattle Genetics; Non-Financial Interests, Institutional, Advisory Role: Third Rock Ventures; Financial Interests, Institutional, Research Grant: Amgen; Financial Interests, Institutional, Research Grant: BioNTech; Financial Interests, Institutional, Research Grant: BMS; Financial Interests, Institutional, Research Grant: MSD; Financial Interests, Institutional, Research Grant: Novartis. All other authors have declared no conflicts of interest.