Transcatheter arterial chemoembolisation combined with lenvatinib plus camrelizumab as conversion therapy for unresectable hepatocellular carcinoma: a single-arm, multicentre, prospective study

Background: The synergistic effect of locoregional therapy in combination with systemic therapy as a conversion therapy for unresectable hepatocellular carcinoma (uHCC) is unclear. The purpose of this study was to evaluate the efficacy and safety of transcatheter arterial chemoembolisation (TACE) combined with lenvatinib and camrelizumab (TACE + LEN + CAM) as conversion therapy for uHCC.Methods: This single-arm, multicentre, prospective study was conducted at nine hospitals in China. Patients (aged 18-75 years) diagnosed with uHCC, an Eastern Cooperative Oncology Group performance score (ECOG-PS) of 0-1 and Child-Pugh class A received camrelizumab (200 mg, every 3 weeks) and lenvatinib (bodyweight >= 60 kg: 12 mg/day; <60 kg: 8 mg/day) after TACE treatment. Surgery was performed after tumour was assessed as meeting the criteria for resection. Patients who did not meet the criteria for surgery continued to receive triple therapy until disease progression or intolerable toxicity. Primary endpoints were objective response rate (ORR) according to the modified Response Evaluation Criteria in Solid Tumours (mRECIST) and safety. Secondary endpoints included the surgical conversion rate, radical (R0) resection rate, and disease control rate (DCR). This study was registered with Chinese Clinical Trial Registry (ChiCTR2100050410).Findings: Between Oct 25, 2021, and July 20, 2022, 55 patients were enrolled. As of the data cutoff on June 1, 2023, the median follow-up was 13.3 months (IQR 10.6-15.9 months). The best tumour response to triple therapy was complete response (CR) in 9 (16.4%) patients, partial response (PR) in 33 (60.0%) patients, stable disease (SD) in 5 (9.1%) patients, or progressive disease (PD) in 7 (12.7%) patients. The ORR was 76.4% (42/55, 95% CI, 65.2-87.6%), and the DCR was 85.5% (47/55, 95% CI, 76.2-94.8%) per mRECIST. Twenty-four (43.6%) of the 55 patients suffered from grade 3-4 treatment-related adverse events (TRAEs). No grade 5 TRAEs occurred. A total of 30 (30/55, 54.5%) patients were converted to resectable HCC and 29 (29/55, 52.7%) patients underwent resection. The R0 resection rate was 96.6% (28/29). The major pathologic response (MPR) and pathologic complete response (pCR) rates in the surgery population were 65.5% (19/29) and 20.7% (6/29), respectively. Only one patient developed a Clavien-Dindo IIIa complication (abdominal infection). No Clavien-Dindo IIIb-V complications occurred. The median OS and median PFS were not reached.Interpretation: The triple therapy (TACE + LEN + CAM) is promising active for uHCC with a manageable safety. Moreover, triple therapy has good conversion efficiency and the surgery after conversion therapy is feasible and safe. To elucidate whether patients with uHCC accepting surgical treatment after the triple therapy can achieve better survival benefits than those who receive triple therapy only, well-designed randomised controlled trials are needed.