Real-world experience with first- versus second-line cemiplimab for advanced basal cell carcinoma

Background: The anti-PD1 antibody (PD1i) cemiplimab is approved as second-line treatment for locally advanced or metastatic basal cell carcinoma (BCC), resulting in an ORR of 20–30 %. This study aimed to investigate the efficacy of cemiplimab as first-line or second-line treatment of BCC in a German real-world patient cohort. Methods: Patients with histologically confirmed locally advanced or metastatic BCC who were treated with cemiplimab were retrospectively identified from the prospective multicenter real-world skin cancer registry ADOREG. Study endpoints were overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). Therapy outcome was compared between patients receiving first-line cemiplimab and patients treated with cemiplimab in second-line. Results: 37 patients from 17 skin cancer centers were identified who received cemiplimab. The median follow-up after start of any first-line treatment was 37.1 months, and 17.9 months after initiation of any cemiplimab treatment. Patients who received first-line cemiplimab (n = 8) had an ORR of 62.5 %, compared to an ORR of 31.0 % for patients who received second-line cemiplimab (n = 29); Median PFS was 19.8 months for first-line cemiplimab and 5.3 months for second-line cemiplimab. Reinduction with HHIs after progression on second-line cemiplimab resulted in an ORR of 20.0 % and a median PFS of 3.8 months. Conclusion: We demonstrate a comparable outcome for cemiplimab as second-line treatment of BCC in our real-world patient cohort as reported in previous registration studies. Additionally, we found a trend for a more favorable outcome in first-line therapy, suggesting a rationale to further investigate cemiplimab as first-line treatment of advanced BCC.