Tiragolumab with atezolizumab and bevacizumab in unresectable hepatocellular carcinoma

A phase 1b-2 study recently published on The Lancet Oncology, showed that the addition of anti-TIGIT monoclonal antibody tiragolumab to atezolizumab and bevacizumab might be more clinically active than atezolizumab plus bevacizumab alone in unresectable hepatocellular carcinoma.

TIGIT is an immune checkpoint regulator implicated in many cancers, including unresectable hepatocellular carcinoma. For this randomised, open-label, phase 1b–2 study, authors randomly assigned 59 patients with previously untreated locally advanced unresectable hepatocellular carcinoma to receive tiragolumab plus atezolizumab plus bevacizumab or atezolizumab plus bevacizumab. After a median follow-up of 20.6 months and 14 months respectively, the confirmed objective response rate was 43% in the tiragolumab plus atezolizumab plus bevacizumab group and 11% in the atezolizumab plus bevacizumab group. Median progression-free survival was longer in the tiragolumab plus atezolizumab plus bevacizumab group than in the atezolizumab plus bevacizumab group (median 12·3 months vs 4·2 months). The addition of tiragolumab to atezolizumab plus bevacizumab did not appear to result in a substantial worsening of treatment-related or immune-mediated adverse events, and no new safety signals were identified. «The addition of tiragolumab to atezolizumab plus bevacizumab showed improved objective response rate and progression-free survival benefit compared with atezolizumab plus bevacizumab alone», authors say. «Results from our study suggest improved clinical activity when tiragolumab is added to atezolizumab plus bevacizumab for patients with unresectable hepatocellular carcinoma and could represent a promising novel first-line treatment option. These data provide a rationale for further investigation of tiragolumab plus atezolizumab plus bevacizumab in unresectable hepatocellular carcinoma. The phase 3 IMbrave 152/SKYSCRAPER-14 study is investigating atezolizumab plus bevacizumab with or without tiragolumab in patients with untreated locally advanced or metastatic hepatocellular carcinoma».