Therapeutic Modifications without Discontinuation of Atezolizumab Plus Bevacizumab Therapy Are Associated with Favorable Overall Survival and Time to Progression in Patients with Unresectable Hepatocellular Carcinoma

SIMPLE SUMMARY: We aimed to evaluate the impact of therapeutic modifications of atezolizumab (Atezo) plus bevacizumab (Bev) therapy (Atezo/Bev) in the case of intolerable adverse events on the prognosis of patients with unresectable hepatocellular carcinoma. Therapeutic modifications included the interruption or discontinuation of both Atezo and Bev, and the reduction, interruption, or discontinuation of Bev alone. Patients with therapeutic modifications other than the discontinuation of both Atezo and Bev had favorable overall survival and time to progression. In contrast, those with the discontinuation of both Atezo and Bev without other therapeutic modifications were associated with unfavorable overall survival and time to progression. Modified albumin–bilirubin grade 2b liver function at the initiation of Atezo/Bev or experience of immune-related adverse events could increase the risk of discontinuation of both Atezo and Bev without other therapeutic modifications. Avoiding the discontinuation of both Atezo and Bev without other therapeutic modifications may be the optimal management of unresectable hepatocellular carcinoma. ABSTRACT: We retrospectively evaluated the impact of therapeutic modifications of atezolizumab (Atezo) plus bevacizumab (Bev) therapy (Atezo/Bev), including the interruption or discontinuation of both Atezo and Bev, and the reduction or discontinuation of Bev, on the outcome of patients with unresectable hepatocellular carcinoma (uHCC) (median observation period: 9.40 months). One hundred uHCC from five hospitals were included. Therapeutic modifications without discontinuation of both Atezo and Bev (n = 46) were associated with favorable overall survival (median not reached; hazard ratio (HR): 0.23) and time to progression (median: 10.00 months; HR: 0.23) with no therapeutic modification defined as the reference. In contrast, the discontinuation of both Atezo and Bev without other therapeutic modifications (n = 20) was associated with unfavorable overall survival (median: 9.63 months; HR: 2.72) and time to progression (median: 2.53 months; HR: 2.78). Patients with modified albumin–bilirubin grade 2b liver function (n = 43) or immune-related adverse events (irAEs) (n = 31) discontinued both Atezo and Bev without other therapeutic modifications more frequently (30.2% and 35.5%, respectively) than those with modified albumin–bilirubin grade 1 (10.2%) and without irAEs (13.0%). Patients with objective response (n = 48) experienced irAEs more frequently (n = 21) than those without (n = 10) (p = 0.027). Avoiding the discontinuation of both Atezo and Bev without other therapeutic modifications may be the optimal management of uHCC.