Early experience of atezolizumab plus bevacizumab therapy in Japanese patients with unresectable hepatocellular carcinoma in real-world practice.

Background. We aimed to investigate the efficacy and safety of atezolizumab plus bevacizumab therapy in patients with unresectable hepatocellular carcinoma (u-HCC) based on whether they had previously received systemic therapy, as well as the association of atezolizumab plus bevacizumab with early alpha-fetoprotein (AFP) response in real-world practice. Methods. A total of 52 patients with u-HCC were treated with atezolizumab plus bevacizumab between October 2020 and April 2021. The Response Evaluation Criteria in Solid Tumors (RECIST) and modified RECIST were used to evaluate radiological responses. Results. The patients received atezolizumab plus bevacizumab as 1st-line (n = 23), 2nd-line (n = 16), 3rd-line (n = 6), 4th-line (n = 3), 5th-line (n = 3), or 6th-line (n = 1) therapy. According to RECIST, the objective response rate (ORR) and disease control rate (DCR) in all patients were 15.4% and 57.7%. In the 1st-line patients, ORR and DCR based on RECIST 1.1 were 27.3% and 81.8%. The median time to progression (TTP) assessed by RECIST was significantly longer among patients receiving atezolizumab plus bevacizumab as 1st-line therapy than in patients receiving atezolizumab plus bevacizumab as later-line therapy (P < 0.001). Patients with an AFP response (reduction ≥ 20% from baseline) at 6 weeks had a significantly longer TTP assessed by RECIST than those without an AFP response (P = 0.02). Conclusion. Patients who received atezolizumab plus bevacizumab as 1st-line therapy had better clinical outcome than those who received atezolizumab plus bevacizumab in later lines. The AFP response at 6 weeks could be a predictor of disease progression.