946P Sintilimab plus lenvatinib as conversion therapy in patients with unresectable hepatocellular carcinoma: A prospective, non-randomized, open-label, phase II, expansion cohort study

Hepatocellular carcinoma (HCC) patients (pts) with major vascular invasion (MVI) or extrahepatic metastases were generally recommended systemic treatment by guidelines, and pts have missed the opportunity for curative resection. Conversion therapy that can convert unresectable HCC into resectable HCC may improve patient survival. Here we report the Sintilimab plus Lenvatini as a conversion therapy for unresectable HCC. Briefly, the main inclusion criteria of the study was: Aged 18 to 75 years unresectable HCC pts diagnosed pathologically and/or radiologically, with at least one measurable lesion (mRECIST). The criteria for Successful Conversion: 1. Child-Pugh score < 7. 2. ECOG PS score ≤1. 3. Downstaging to BCLC-A or PR according to mRECIST, and extrahepatic lesions can be resected at the same time. 4. Intact vascular structure of the reserved liver and sufficient FLR. A total of 137 pts were enrolled in the study by April 10, 2023 and accepted the Sintilimab plus Lenvatinib as conversion therapy,100 pts were finally included for evaluation, in which 58 pts with PVTT (39 pts were classified as VP4), 4 with IVCTT and 7 with both. 26 pts had extrahepatic metastases, and 92 pts were HBV-positive. According to mRECIST, the ORR was 54% and DCR was 77%. Successful conversion rate based on radiology was 51%, and 47% pts received hepatectomy. With a median follow-up of 17 months (range, 1-43), the median OS was 25 months (95% CI, 15.9–34.1) among all pts, the median OS of the pts was not reached [95% CI not reached] in the surgical group and 15 months (95% CI, 10.3–19.7) in the non-surgical group. The median RFS was 25 months (95% CI, 13.6–36.4) in the surgical group and the median PFS was 7 months (95% CI, 3.5–10.5) in the non-surgical group. All pts were evaluable for toxicity, and 83 (83%) pts had at least one treatment-related AE (TRAE). TRAEs occurring in ≥10% of pts were rash (27%), hypertension (18%), hand foot syndrome (17%), and diarrhoea (16%). 28 pts had grade 3 TRAEs. The combination therapy of Sintilimab plus Lenvatinib can be reviewed as a reasonable and promising conversion therapy option for unresectable HCC with safety and effectiveness.