Association of immune related adverse events with superior outcomes in patients with hepatocellular carcinoma (HCC) treated with nivolumab.

Abstract

e16630 Background: Nivolumab, an anti-PD1 antibody, is FDA approved in patients (pts) with HCC. Anti-PD-1 promotes hyperstimulation of host immunity and is associated with a spectrum of toxicities known as immune-related adverse events (irAEs). In other malignancies, higher rates of irAEs are associated with improved cancer outcomes. This study shows correlation between irAEs and efficacy in pts with HCC treated with nivolumab. Methods: Demographic and toxicity data were collected retrospectively on all pts with HCC treated with nivolumab at a single institution from Jan 2012 – Sept 2019. Response was evaluated using RECISTv1.1. Adverse events were assessed according to CTCAEv5.0. Categorical variables were assessed by Fisher's exact test. Survival was estimated with the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate analyses were performed by the Cox-regression model. Results: 30 pts were treated; irAEs were detected in 16 (53%). There was no difference in baseline characteristics among those who did and did not experience irAEs (Table). The most frequent irAEs were elevated AST/ALT (n = 7; 44%), rash (n = 4; 25%), and hypothyroid (n = 4; 25%). 3 G3 (rash and transaminitis) and 1 G4 AE (pured red cell apalasia) were observed. Among all pts, overall response rate (RR) and disease control rate (DCR) were 13 and 50%, respectively. Median progression free survival (PFS) and overall survival (OS) were 27 and 56 weeks (w), respectively. The RR and DCR were higher among irAEs vs non-irAEs, although this did not reach statistical significance (RR 25 vs 0%; p = 0.05; DCR 62 vs 35%; p = 0.19). Median PFS and OS were longer in those with irAEs vs non-irAE; PFS 33 vs 16 w (HR: 0.26; CI 95%: 0.076-0.89; p = 0.028); (OS 69 vs 21 w HR: 0.18; CI 95%: 0.05-0.58; p = 0.002). On multivariate analysis, viral etiology was associated with prolonged PFS (p = 0.002) and MELD was associated with reduced OS (p = 0.004). Conclusions: Development of irAEs was associated with prolonged PFS and OS in pts with HCC treated with nivolumab. Further study is needed to determine whether type of irAE, onset time, or duration affect cancer outcomes. [Table: see text]