Supplementary Material for: A Phase 2, Prospective, Multicenter, Single-arm Trial of Transarterial Chemoembolization Therapy in Combination Strategy with Lenvatinib in Patients with Unresectable Intermediate-stage Hepatocellular Carcinoma: TACTICS-L Trial

Background: Transarterial chemoembolization (TACE) is the standard treatment for unresectable intermediate-stage hepatocellular carcinoma (HCC), but recurrence after TACE is common. The present phase II, prospective, multicenter, single-arm trial, the TACTICS-L trial, investigated the efficacy and safety of TACE plus lenvatinib (LEN), a drug that more strongly promotes vascular normalization and has a better ORR than sorafenib (jRCTs031180074). Patients and Methods: Participants were patients with HCC who had not previously received systemic therapy, hepatic arterial infusion chemotherapy, or immunotherapy, and who were ineligible for resection or percutaneous ablation therapy. LEN was to be administered 14–21 days before the first TACE, stopped 2 days before TACE, and resumed 3 days after TACE. Key inclusion criteria were unresectable HCC, Child-Pugh A liver function, 0–2 prior TACE sessions, tumor size ≤10 cm, number of tumors ≤10, and ECOG performance status 0–1. Key exclusion criteria were vascular invasion and extrahepatic spread. The primary endpoint was PFS by RECICL, and secondary endpoints were time to untreatable progression, objective response rate (ORR), OS, and safety. Results: A total of 62 HCC patients were enrolled in this trial. The median age was 72 years, 77.4% of patients were men, and 95.2% had PS 0. The primary endpoint of median PFS was 28.0 months (95% CI 25.1–31.0) after a minimum 24 months of follow-up. The secondary endpoint of median OS was not reached (95% CI 35.5 months–NR). LEN-TACE achieved a high response rate and high CR rate (4 weeks after the first TACE: ORR 79.0%, CR rate 53.2%; best response: ORR 88.7%, CR rate 67.7%) by RECICL. Exploratory subgroup analyses showed that the characteristics of responders/nonresponders (ORR and CR) were similar, and that LEN-TACE would be effective in all subgroups, including the population in whom TACE alone would be less likely to be curative (e.g., patients with the nonsimple nodular type or a high tumor burden). The relative dose intensity of LEN before the first TACE was important for achieving higher CR/ORR by LEN-TACE. No new safety concerns were observed. Conclusion: The results of this trial provide encouraging evidence supporting the efficacy and favorable safety profile of LEN-TACE in patients who are ineligible for locoregional therapy.