Comparison between Nivolumab and Regorafenib as Second-line Systemic Therapies after Sorafenib Failure in Patients with Hepatocellular Carcinoma

Purpose: Nivolumab and regorafenib are second-line therapies for patients with advanced hepatocellular carcinoma (HCC). We aimed to compare the effectiveness of nivolumab and regorafenib. Materials and Methods: We retrospectively reviewed patients with HCC treated with nivolumab or regorafenib after sorafenib failure. Progression-free survival (PFS) and overall survival (OS) were analyzed. An inverse probability of treatment weighting using the propensity score (PS) was performed to reduce treatment selection bias. Results: Among the 189 patients recruited, 137 and 52 patients received regorafenib and nivolumab after sorafenib failure, respectively. Nivolumab users showed higher Child-Pugh B patients (42.3% vs. 24.1%) and shorter median sorafenib maintenance (2.2 months vs. 3.5 months) compared to regorafenib users. Nivolumab users showed shorter median OS (4.2 months vs. 7.4 months, p=0.045) than regorafenib users and similar median PFS (1.8 months vs. 2.7 months, p=0.070). However, the median overall and PFS did not differ between the two treatment groups after the 1:1 PS matching (log-rank p=0.810 and 0.810, respectively) and after the stabilized inverse probability of treatment weighting (log-rank p=0.445 and 0.878, respectively). In addition, covariate-adjusted Cox regression analyses showed that overall and PFS did not significantly differ between nivolumab and regorafenib users after 1:1 PS matching and stabilized inverse probability of treatment weighting (all p>0.05). Conclusion: Clinical outcomes of patients treated with nivolumab and regorafenib after sorafenib treatment failure did not differ significantly.