Clinical determinants of clinical response to Sonidegib in advanced basal cell carcinoma: a monocenter experience.

OBJECTIVE:The purpose of this study is to evaluate the clinical determinants of complete response in locally advanced basal cell carcinoma (laBCC) patients receiving Sonidegib in a real-life, retrospective, observational study.  Hedgehog pathway inhibitors (Vismodegib and Sonidegib) are approved for the systemic treatment of locally advanced basal cell carcinoma (laBCC). The objective response rate was the primary endpoint of the trials for both drugs. PATIENTS AND METHODS:Adult patients with laBCC treated with Sonidegib at the Dermato-Oncology Unit of IFO San Gallicano between June 2020 and September 2022 were included in the study. Patient, tumor, and treatment characteristics were recorded. The complete response rate was the primary outcome. The median time to the best response and complete response were the secondary outcomes. Treatment-related adverse events (TRAEs) and dose adjustments were recorded. RESULTS:Of the 19 patients included in the study, eight (42.1%) achieved a complete response, seven (36.8%) had a partial response, and four experienced progressive disease (21%). The median time to the best response was 3 months in the group of patients with partial response (range 2.0-4.0, with three patients not evaluable) and 3.5 months in the group of patients with complete response (range 2-5). TRAEs occurred in 14 (73.6%) patients, with 8 (57.1%) reporting ≤2 TRAE categories and 6 (42.8%) >2. A total of 78.9% of patients received a modified treatment schedule; 12.5% of patients who achieved a complete response received full dosage from the beginning to the end of treatment, compared with 27.3% of those with a partial response. CONCLUSIONS:The associations between the clinical outcome of interest (objective response rate) and the clinicopathological and treatment characteristics were evaluated. No statistically significant association was observed. Our analysis confirms the observation that no statistically significant correlation exists between clinical response and Sonidegib alternate dose regimen.