Safety and efficacy of lenvatinib by starting dose based on body weight in patients with unresectable hepatocellular carcinoma in REFLECT.

BACKGROUND REFLECT was an open-label, phase 3 study comparing the efficacy and safety of lenvatinib versus sorafenib in patients with unresectable hepatocellular carcinoma (uHCC). Based on phase 2 study (Study 202) results, body weight-based dosing for lenvatinib was used in REFLECT to minimize dose disruptions and modifications needed to address dose-related adverse events. This post hoc analysis of REFLECT data assessed lenvatinib efficacy and safety by body weight group. METHODS The study randomly administered lenvatinib (n = 476) or sorafenib (n = 475) to patients with untreated (no prior systemic therapy) uHCC. Lenvatinib starting-dose data were stratified by body weight: patients weighing < 60 kg received 8 mg/day; patients weighing ≥ 60 kg received 12 mg/day. Overall survival (OS), progression-free survival (PFS), objective response rate, and safety were assessed. RESULTS Survival outcomes and safety profiles appeared similar between the two body-weight-based lenvatinib starting-dose groups. Median OS for patients in the < 60 kg body weight group (n = 153) was 13.4 months [95% confidence interval (CI) 10.5-15.7] compared to 13.7 months (95% CI 12.0-15.6) in the ≥ 60 kg body weight group (n = 325). In both lenvatinib groups, PFS was 7.4 months (< 60 kg group: 95% CI 5.4-9.2; ≥ 60 kg group: 95% CI 6.9-9.0). Treatment-emergent adverse events (TEAEs) required dose modifications in 43.0% in the < 60 kg body weight group and 57.5% in the ≥ 60 kg body weight group. CONCLUSIONS This exploratory analysis of data from REFLECT indicated that body weight-based lenvatinib dosing in patients with uHCC was successful in maintaining efficacy, with comparable rates of TEAEs and dose modifications in the two body weight groups. CLININCAL TRIAL Trial registration ID: ClinicalTrials.gov # NCT01761266.