Adjuvant treatment with atezolizumab and bevacizumab prolongs recurrence-free survival (RFS), when compared with active surveillance, in patients with hepatocellular carcinoma (HCC), according to research presented at the AACR Annual Meeting 2023.
These results, from the phase 3 IMbrave050 trial, suggest that atezolizumab and bevacizumab may represent a practice-changing adjuvant treatment option, said study presenter Pierce Chow, MBBS, PhD, of the National Cancer Centre Singapore.
The IMbrave050 trial (ClinicalTrials.gov Identifier: NCT04102098) included 668 patients with HCC who had undergone a curative resection or ablation. They were randomly assigned to receive atezolizumab plus bevacizumab (n=334) or to undergo active surveillance (n=334) until disease recurrence or unacceptable toxicity. Crossover was allowed.
Baseline characteristics were balanced between the arms. The median age was 60 years in the combination arm and 59 years in the active surveillance arm (overall range, 19-89). Most patients were men (82.9% and 83.2%, respectively), were Asian (82.6% and 80.5%), and had undergone resection (87.7% and 87.4%).
The primary endpoint was RFS. The median RFS was not reached in either arm at a median follow-up of 17.4 months. However, the 12-month RFS rate was significantly higher in the atezolizumab-bevacizumab arm than in the active surveillance arm — 78% and 65%, respectively (hazard ratio [HR], 0.72; 95% CI, 0.56-0.93; P =.012).
Disease recurrence was improved with atezolizumab and bevacizumab as well. The 12-month recurrence rate was 20% with the combination and 34% with active surveillance (HR, 0.67; 95% CI, 0.52-0.88; P =.003).
The overall survival data were immature. Twenty-seven patients died in the combination arm, and 20 died in the active surveillance arm. There were similar numbers of deaths due to recurrence between the arms. There were 3 COVID-19-related deaths, all in the combination arm.
Among patients who received atezolizumab and bevacizumab, 34.9% had a grade 3-4 treatment-related adverse event (TRAE), and 13.3% had a serious TRAE. Two patients had a fatal TRAE (esophageal varices hemorrhage and ischemic stroke).
“IMbrave050 is a landmark study and the first to demonstrate an efficacious adjuvant therapy for patients with HCC who have undergone surgical resection or ablation,” Dr Chow said in a statement. “These results have established a benchmark in adjuvant therapy for HCC.”
Disclosures: This research was supported by F. Hoffmann-La Roche Ltd. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
1. Chow P, Chen M, Cheng A-L, et al. IMbrave050: Phase 3 study of adjuvant atezolizumab + bevacizumab versus active surveillance in patients with hepatocellular carcinoma (HCC) at high risk of disease recurrence following resection or ablation. AACR 2023. April 14-19, 2023. Abstract CT003.
2. Adjuvant treatment with atezolizumab and bevacizumab may delay recurrence after surgical resection in patients with liver cancer. News release. American Association for Cancer Research. Published April 16, 2023.