Effects of Sonidegib Following Dose Reduction and Treatment Interruption in Patients with Advanced Basal Cell Carcinoma During 42-Month BOLT Trial

Introduction: Sonidegib is a Hedgehog pathway inhibitor approved to treat locally advanced basal cell carcinoma and, depending on regulatory approval, metastatic basal cell carcinoma. Results from the BOLT study demonstrated robust efficacy and continued tolerability through 42 months. This analysis evaluated the impact of sonidegib dose reductions and interruptions in patients with advanced basal cell carcinoma through 42 months. Methods: BOLT was a randomized, double-blind, multicenter, phase 2 study. Adults with no previous Hedgehog pathway inhibitor therapy were randomized 1:2 to sonidegib 200 or 800 mg once daily. Primary endpoint was objective response rate. Dose modifications were permitted in patients unable to tolerate the dosing schedule or if a treatment-related adverse event was suspected. Results: The incidence of dose interruptions was similar between the 200- and 800-mg groups (68.4% vs 65.3%, respectively). Dose reductions occurred more frequently in patients receiving sonidegib 800 mg (36.7%) than 200 mg (16.5%). Overall response rate for all patients receiving sonidegib 200 mg daily was 48.1% and was similar to those of patients without dose reduction or interruption (48.5%) and patients with at least one dose reduction or interruption (46.2%). Conclusion: Dose reductions and interruptions were practical and did not impact the efficacy of sonidegib. In patients with advanced basal cell carcinoma who necessitate long-term treatment, dose interruptions may be beneficial for continued treatment and disease control. Trial registration: ClinicalTrials.gov identifier, NCT01327053.