The safety of atezolizumab plus bevacizumab (atezo/bev) treatment in Chinese patients (pts) with hepatocellular carcinoma (HCC) with active hepatitis B virus (HBV) infection: Results from the TALENTop study.

e16168 Background: HCC pts with active HBV infection were excluded from most clinical trials involving immune checkpoint inhibitors because of safety concerns. We are aiming to evaluate the treatment safety of atezo/bev treatment in the TALENTop study (NCT04649489) which enrolled a large number of pts with active HBV infection. Methods: The TALENTop study is to clarify whether liver resection may provide additional benefits in Chinese HCC pts with macrovascular invasion who responded to conversion therapy with atezo/bev. After two versions of protocol modification, pts with active HBV infection were allowed. This study is ongoing, and the primary analysis is expected later. The current analysis is to evaluate treatment safety in pts with active HBV infection in the induction phase when pts received 3 cycles of atezo/bev and 1 cycle of atezo monotherapy. We compared the adverse events (AEs) between pts with active (baseline serum HBV-DNA ≥500 IU/mL) or inactive HBV infection (HBV-DNA < 500 IU/mL). All pts with detectable HBV-DNA or positive hepatitis B surface antigen received oral antiviral therapy throughout the study. Results: From Apr 2021 to Sep 2023, 296 pts were enrolled and completed induction phase therapy of atezo/bev. 274 pts (92.6%) had HBV-related HCC, and 133 pts (44.9%) had active HBV infection. The baseline characteristics were mainly balanced between groups, except pts with active HBV infection were younger (52 vs 56 years, P = 0.024), had larger tumor size (the diameter of target lesion 88.3 vs 78.1 mm, P = 0.007), and had higher album-bilirubin score (-2.62 vs -2.80, P < 0.001). In the induction phase, the AEs of any grade were higher in pts with active HBV infection (88.0% vs 73.6%, P = 0.002). However, the grade ≥3 AEs (20.3% vs 17.8%, P = 0.584), grade ≥3 treatment-related AEs (12.0% vs 12.3%, P = 0.950) and serious AEs (15.0% vs 13.5%, P = 0.706) were comparable between pts with active and inactive HBV infection. Additionally, the incidence of liver-related AEs was also comparable, including increased AST (17.3% vs 16.0%), increased ALT (17.3% vs 14.7%), and increased bilirubin (10.5% vs 12.9%). AEs leading to treatment withdrawal were also comparable (6.0% vs 6.1%, P = 0.966). In pts with active HBV infection, 20.8% remained serum HBV-DNA ≥500 IU/mL at the end of cycle 4. Conclusions: Active HBV infection did not compromise the safety of atezo/bev therapy. These findings could support that, with concurrent use of oral antiviral therapy, pts with active HBV infection should be not excluded from clinical trials or delayed for immunotherapy. Clinical trial information: NCT04649489 .