Abstract 833P
Background
Cemiplimab is the first approved systemic treatment for patients with advanced cutaneous squamous cell carcinoma (cSCC). We have already reported previously acute toxicities and overall responses from a real-world experience of 18 Italian centers.
Methods
We analyzed the long-term follow up of the 134 patients previously analyzed in the retrospective, observational study REAL CEMI. We assessed late toxicities rate, considering treatment-related adverse events (trAEs) that occurred after at least 6 months since cemiplimab start, the updated objective response rate (ORR) and disease control rate (DCR), progression-free survival (PFS) and overall survival (OS). We explored correlations between clinical outcomes and baseline clinical-pathological characteristics, and we carried out a descriptive analysis of patients who obtained a complete response (CR).
Results
At a median follow up (range 1-32) of 14 months, cemiplimab was ongoing in 29 patients (21,6%) with a median duration of treatment of 7 months (1-29+). Late trAEs occurred in 11,2% of cases, with a median time to onset of 12 months. Most of them were grade (G) 1/2 (73,3%), but two patients stopped cemiplimab due to a late adverse event (G3 maculopapular rash pemphigoid-like and G3 nausea and vomiting). Updated ORR was 58,9% and DCR was 72,4%. Median PFS was 9 (95% confidence interval (CI) 2.45-15.55) months and median OS was 21 (95% CI 9.41-32.59) months. In the multivariate analysis, the best response obtained, and Performance Status were found to be significantly related to both PFS and OS, while chronic intake of steroids was only related to PFS. Considering the subgroup of 26 (19,4%) patients with CR: median time to CR was 4 months (1-23) and median duration of treatment after obtaining CR 8 months (0-35+); at the data cut-off, 19 (73,1%) patients had stopped treatment with cemiplimab, and all these patients had ongoing complete response.
Conclusions
At a longer follow up of a real-world study, the activity of cemiplimab is confirmed, with a relatively low number of late toxicities. However, some trAEs may occur even after several months from the start of treatment. Complete response is often maintained for long time.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.