Early response and safety of atezolizumab plus bevacizumab for unresectable hepatocellular carcinoma in patients who do not meet IMbrave150 eligibility criteria

Hepatol Res. 2021 Sep;51(9):979-989. doi: 10.1111/hepr.13693. Epub 2021 Jul 20.

Abstract

Aim: A clinical trial (IMbrave150) indicated the efficacy and safety of atezolizumab plus bevacizumab for patients with unresectable hepatocellular carcinoma (HCC). In this study, we evaluated this therapeutic combination in a real-world setting, with a focus on patients who did not meet the IMbrave150 eligibility criteria.

Methods: In this multicenter study, patients with unresectable HCC treated with atezolizumab plus bevacizumab between October 2020 and May 2021 were screened. In patients who did not meet IMbrave150 eligibility criteria, treatment responses and safety at 6 and 12 weeks were evaluated.

Results: Atezolizumab plus bevacizumab was initiated in 64 patients, including 46 patients (71.9%) who did not meet IMbrave150 eligibility criteria. Most of these patients had a history of systemic therapy (44/46). The objective response rate and disease control rate observed using Response Evaluation Criteria in Solid Tumors 1.1 were 5.2% and 82.8% at 6 weeks and 10.0% and 84.0% at 12 weeks, respectively; these rates were similar between patients who met and did not meet the IMbrave150 criteria. Ten patients experienced progressive disease (PD) at 6 weeks. Portal vein tumor thrombosis was significantly associated with PD (p = 0.039); none of the 15 patients with hepatitis B virus-related HCC experienced PD (p = 0.050). The most common adverse events of grade 3 or higher were aspartate aminotransferase elevation (n = 8, 13.8%) and the safety profile was similar between patients who met and did not meet the IMbrave150 criteria.

Conclusion: Most patients treated with atezolizumab plus bevacizumab did not meet the IMbrave150 criteria; however, the combination therapy showed good safety and efficacy at the early treatment phase.

Keywords: atezolizumab; bevacizumab; early response; hepatocellular carcinoma.