Efficacy and Safety of Durvalumab/Tremelimumab in Unresectable Hepatocellular Carcinoma as Immune Checkpoint Inhibitor Rechallenge Following Atezolizumab/Bevacizumab Treatment.

Background: While guidelines recommend immune checkpoint inhibitor (ICI) rechallenge as second-line therapy for unresectable hepatocellular carcinoma (HCC), data supporting this remain limited, particularly regarding a standard regimen for first- and second-line treatments. Tremelimumab/durvalumab was recently approved but data on ICI rechallenge are lacking.

Objectives: The purpose of this study was to evaluate the early efficacy and safety of tremelimumab/durvalumab for HCC as an ICI rechallenge following initial ICI therapy with atezolizumab/bevacizumab.

Patients And Methods: This multicenter retrospective study included patients with HCC who underwent treatment with tremelimumab/durvalumab, with relevant available clinical information. We evaluated the safety and efficacy of tremelimumab/durvalumab as ICI rechallenge following initial treatment with atezolizumab/bevacizumab. We analyzed the outcomes in patients who underwent tremelimumab/durvalumab as an ICI rechallenge and those who received tremelimumab/durvalumab as their initial ICI therapy RESULT: A total of 45 patients treated with tremelimumab/durvalumab were included, with 55.6% (25/45) undergoing ICI rechallenge. The objective-response and disease-control rates in patients who underwent ICI rechallenge were 14.3% (3/21) and 47.6% (10/21), respectively, similar to those in patients initially treated with tremelimumab/durvalumab. All patients (n = 3) who experienced the best response to progressive disease (PD) with initial atezolizumab/bevacizumab experienced PD during ICI rechallenge. The incidence rates of adverse events were similar between patient groups treated with tremelimumab/durvalumab as ICI rechallenge and initial ICI. Among patients experiencing immune-related adverse events (irAEs) with atezolizumab/bevacizumab, 75% (3/4) encountered similar irAEs during ICI rechallenge.

Conclusion: Early safety and efficacy profiles of durvalumab/tremelimumab as ICI rechallenge are satisfactory.