Association of age with differences in immune related adverse events and survival of patients with advanced nonsmall cell lung cancer receiving pembrolizumab or nivolumab

Objectives To explore the association of age with development of immune related adverse events (irAE) and survival in patients with advanced nonsmall cell lung cancer (aNSCLC) receiving programmed cell death 1 antibodies (PD-1 Ab) outside of clinical trials. Methods A multicenter retrospective study of PD-1 Ab prescription for patients with aNSCLC between 06/2015–11/2018 at BC Cancer. Multivariable (MVA) logistic regression identified baseline variables associated with irAE manifested within 3 months of PD-1 Ab initiation. Overall survival (OS) analyzed in a propensity-score matched cohort and survival outcomes compared between age groups by stratified log-rank. Six-week landmark analysis was performed and OS compared between patients with interrupted versus continuous treatment by log-rank. Results Of 527 patients, 40.6% were age ≤ 64 years, 40.6% were 65–74 years, and 18.8% were ≥ 75 years. In MVA, ECOG performance status 2/3 (p = .034), squamous histology (p = .031), and nivolumab therapy (vs. pembrolizumab, p = .012) were associated with increased odds of irAE by 3 months of treatment. Across age groups no difference existed in any grade irAE (p = .98), hospitalization (p = 1.0), or corticosteroids use (p = .51). The propensity score–matched survival analysis comprised 77 patients from each age group; all covariates were balanced. OS did not differ significantly by age in the matched cohort (p = .17). Treatment interruption due to irAE at 6 weeks was more common in patient ≥75 years (vs. <75, p = .055) and correlated with lower OS (p = .002). Conclusion In this cohort of patients with aNSCLC treated in routine clinical practice with PD-1 Ab, immune-toxicity and observed survival were similar amongst age groups.