Aim: INVIDIa was a retrospective, multicenter study, exploring the clinical efficacy of influenza vaccine in 300 cancer patients undergoing immunotherapy. Overall survival (OS) was immature at the initial report. Methods: We reported the final OS analysis from the original study population and within subgroups. Results: Both at the univariate and multivariate analysis, the occurrence of influenza syndrome (IS) was significantly related to better OS in the overall population (OR: 0.53 [95% CI: 0.32-0.88]; p = 0.01). In the lung cancer subgroup, receiving flu vaccine and/or developing IS was related to better OS (p = 0.04). Within elderly patients, the flu vaccine was the main variable for the relative OS advantage (p = 0.05). Conclusion: Receiving the flu vaccine and/or developing IS was related to better OS within the INVIDIa population.
Keywords: flu vaccine; immune checkpoint inhibitors; immunotherapy; influenza syndrome; influenza vaccination; overall survival.