P8‐34: The relation between immune‐related adverse events and therapeutic effects of nivolumab or pembrolizumab monotherapy for patients with non‐small cell lung cancer

Background and Aims: The relation between immune-related adverse events (irAEs) and the therapeutic effect of immune checkpoint inhibition (ICI) has been discussed. We assessed the relationship between irAE occurrence and ICI efficacy. Methods: We retrospectively analyzed all advanced NSCLC patients receiving nivolumab or pembrolizumab monotherapy for > 4 weeks, without disease progression, between February 2016 and June 2020. Results: Nivolumab group (Nivo): 49 cases, median age (range) 71 (41-84) years, 36 men (73%), ECOG performance status (PS) 0/1/2 in 9/34/6 cases, programmed death ligand-1 tumor proportion score (PD-L1 TPS) 50%/1-49%<1%/unknown in 5/7/9/28 cases. Pembrolizumab group (Pembro): 41 cases, median age 75 (52-89) years, 28 men (68%), PS 0/1/2 in 5/18/18 cases, PD-L1 TPS ≧50%/1-49%/<1%/unknown in 33/8/0/0 cases. Response rate was 22% in Nivo, 49% in Pembro. IrAE occurred in 57% Nivo, 61% Pembro. In Nivo, median progression-free survival (PFS) was 13.2 months in patients with irAE (irAE group), 2.9 months in patients without irAE (non-irAE group) (p=0.001); median overall survival (OS) was 21.4 months in irAE group, 11.1 months in non-irAE group (p=0.005). In Pembro, PFS was 16.1 months in irAE group versus 8.7 months in non-irAE group (p=0.04); OS not reached in irAE group versus 23.4 months in non-irAE group (p=0.017). Conclusions: IrAE occurrence may be associated with the therapeutic effect of ICI.