Background: Anti-programmed cell death protein 1 (PD1)/programmed death-ligand 1(PD-L1) therapy frequently entails immune-related adverse events (irAEs), and biomarkers to predict irAEs are lacking. Although checkpoint inhibitors have been found to reinvigorate T cells, the relevance of autoantibodies remains elusive.
Objective: Our aim was to explore whether IgG autoantibodies directed against coexpressed antigens by tumor tissue and healthy skin correlate with skin irAEs and therapy outcome.
Methods: We measured skin-specific IgG via enzyme-linked immunosorbent assay in patients with non-small cell lung cancer (NSCLC) who received anti-PD1/PD-L1 treatment between July 2015 and September 2017 at the Kantonsspital St. Gallen. Sera were sampled at baseline and during therapy after 8 weeks.
Results: Analysis of publicly available tumor expression data revealed that NSCLC and skin coexpress BP180, BP230, and type VII collagen. A skin irAE developed in 16 of 40 recruited patients (40%). Only elevated anti-BP180 IgG at baseline significantly correlated with the development of skin irAEs (P = .04), therapy response (P = .01), and overall survival (P = .04).
Limitations: The patients were recruited in a single tertiary care center.
Conclusions: Our data suggest that the level of anti-BP180 IgG of NSCLC patients at baseline is associated with better therapy response and overall survival and with a higher probability to develop skin irAEs during anti-PD1/PD-L1 treatment.
Keywords: anti-PD1; autoantibodies; immune checkpoint inhibitors; immune-related adverse events; non-small cell lung cancer; skin rash.
Copyright © 2019 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.