Phase 3 (COSMIC-312) study of cabozantinib (C) in combination with atezolizumab (A) versus sorafenib (S) in patients (pts) with advanced hepatocellular carcinoma (aHCC) who have not received previous systemic anticancer therapy.

Abstract

TPS4157 Background: C inhibits tyrosine kinases involved in tumor growth, angiogenesis, and immune regulation, including MET, VEGFR, and TAM kinases (Tyro3, AXL, MER). C is approved for treatment of aHCC after prior S based on improved overall survival (OS) vs placebo in the phase 3 CELESTIAL trial (Abou-Alfa NEJM 2018). Standard of care for first-line treatment of aHCC is tyrosine kinase inhibition with S or lenvatinib, and phase 3 trials of immune checkpoint inhibitors (ICIs) in first- and second- line aHCC are ongoing. C may promote an immune-permissive tumor environment, which could enhance response to ICIs. C is being evaluated in combination with the anti-PD-L1 antibody A in multiple tumor types including HCC in a phase 1 study; and dose, preliminary clinical activity, and safety have been established in aRCC (Agarwal Ann Oncol 2018). A in combination with bevacizumab, an anti-VEGF antibody, has shown preliminary clinical activity in first-line aHCC (Pishvaian Ann Oncol 2018). Here, we present the study design of a phase 3 trial of C+A vs S in pts with aHCC who have not received prior systemic therapy. Methods: This international, randomized, open-label phase 3 trial (NCT03755791) is evaluating the efficacy and safety of C+A vs S as first-line treatment for aHCC. Eligibility criteria include age ≥18 years, BCLC stage B or C, Child-Pugh A, ECOG PS 0 or 1, and measurable disease per RECIST 1.1. Patients are randomized 6:3:1 to an experimental arm of C (40 mg qd) + A (1200 mg infusion q3w), a control arm of S (400 mg bid), and an exploratory arm of C monotherapy (60 mg qd). 640 pts are planned at ~200 sites globally. Randomization is stratified by disease etiology (HBV [with or without HCV], HCV [without HBV], or other), region (Asia, other), and the presence of extrahepatic disease and/or macrovascular invasion (yes, no). OS and progression-free survival are coprimary endpoints and objective response rate is a secondary endpoint. Additional endpoints include safety, pharmacokinetics, and correlation of biomarker analyses with clinical outcomes. Enrollment in COSMIC-312 is ongoing. Clinical trial information: NCT03755791.