Supplementary Material for: Rechallenging Unresectable Hepatocellular Carcinoma with the STRIDE Regimen: A Case Report of Significant AFP Response After Atezolizumab-Bevacizumab Intolerance

Abstract: Introduction: Hepatocellular carcinoma (HCC) is a leading cause of cancer worldwide, with immune checkpoint inhibitors (ICIs) revolutionizing treatment of unresectable HCCs. However, limited data exist on rechallenging patients with alternative ICI regimens, such as STRIDE (durvalumab + tremelimumab), following initial treatment failure or intolerance to atezolizumab + bevacizumab. Case Report: A 66-year-old male with advanced cirrhosis, hepatitis C, and a history of alcohol use developed HCC, with an AFP level increasing from 3.4 to 3199. Imaging revealed a 10.7 cm infiltrative mass with portal vein thrombosis, and the patient was diagnosed with Barcelona Clinic Liver Cancer (BCLC) stage C HCC. First-line treatment with atezolizumab + bevacizumab was initiated, but the patient did not tolerate the regimen well, leading to discontinuation. He was switched to the STRIDE regimen, which he tolerated well. After six cycles of durvalumab, significant clinical improvement was noted and a follow-up MRI showed reduced tumor thrombus size, and AFP levels dropped significantly to 2, indicating a sustained or improved therapeutic response. Conclusion: This case suggests that rechallenging with the STRIDE regimen may provide significant clinical benefit in HCC patients intolerant to initial ICI therapy. However, further clinical trials are needed to confirm the efficacy and optimal use of ICI rechallenge strategies in HCC.