Safety and immunogenicity of mRNA vaccines against SARS-CoV-2 in patients with lung cancer receiving immune checkpoint inhibitors: A multicenter observational study in Japan

Patients with cancer have been prioritized for vaccination against severe acute respiratory syndrome coronavirus 2. Nevertheless, there are limited data regarding the safety, efficacy, and risk of developing immune-related adverse events (irAEs) associated with mRNA vaccines in patients with lung cancer, especially those being actively treated with immune checkpoint inhibitors.This multicenter observational study was conducted at nine hospitals in Japan. Patients with lung cancer (≥20 y) actively treated with immune checkpoint inhibitors between 4 weeks prefirst vaccination and 4 weeks postsecond vaccination were enrolled. The primary end point was the incidence of irAEs of any grade on the basis of an assumed incidence without vaccination rate of 35%. Immunogenicity was assessed by measuring anti-spike (S)-IgG antibody levels against severe acute respiratory syndrome coronavirus 2.A total of 126 patients with lung cancer (median age, 71 y; interquartile range, 65-74) were enrolled from May to November 2021 and followed up until December 2021. There were 26 patients (20.6%, 95% confidence interval: 13.9%-28.8%) and seven patients (5.6%, 95% confidence interval: 2.3%-11.1%) who developed irAEs of any grade pre- and postvaccination, respectively, which was lower than the predicted incidence without vaccination. None of the patients experienced exacerbation of preexisting irAE postvaccination. S-IgG antibodies were seroconverted in 96.7% and 100% of the patients with lung cancer and controls, respectively, but antibody levels were significantly lower in patients with lung cancer (p < 0.001).Patients with lung cancer who were actively treated with ICIs were safely vaccinated without an increased incidence of irAEs; however, their vaccine immunogenicity was lower. This requires further evaluation.