Associated Factors to Efficacy and Tolerance of Immunotherapy in Older Patients with Cancer Aged 70 Years and Over: Impact of Coprescriptions

Abstract

Background: Immunotherapy with immune checkpoint blockers (ICB) significantly improves the prognosis for an increasing number of cancers. However, data on geriatric populations taking ICB are rare.

Objective: This study aimed to identify factors associated with the efficacy and tolerance of ICB in an older population.

Patients and methods: This retrospective monocentric study included consecutive patients aged ≥ 70 years with solid cancer who received ICB between January 2018 and December 2019. Efficacy was assessed by progression-free survival (PFS) and tolerance was defined as cessation of immunotherapy due to the occurrence of any adverse event.

Results: One hundred and five patients (65.7% men) were included, mainly at the metastatic stage (95.2%); 50.5% had lung cancer. Most (80%) patients were treated with anti-PD1 (nivolumab, pembrolizumab), 19.1% with anti-PD-L1 (atezolizumab, durvalumab, and avelumab) and 0.9% with anti-CTLA4 ICB (ipilimumab). Median PFS was 3.7 months [95% confidence interval (CI) (2.75-5.70)]. PFS was shorter in univariate analysis when ICB was taken concomitantly with an antiplatelet agent (AP) [hazard ratio (HR) = 1.93; 95% CI (1.22-3.04); p = 0.005]. Tolerance was lower in univariate analysis for lung cancer [odds ratio (OR) = 3.03; 95% CI (1.07-8.56), p < 0.05] and in patients taking proton pump inhibitors (PPI) [OR = 5.50; 95% CI (1.96-15.42), p < 0.001]. There was a trend toward poorer tolerance among patients living alone [OR = 2.26; 95% CI (0.76-6.72); p = 0.14].

Conclusions: In older patients taking ICB for solid cancers, concomitant AP may influence efficacy and concomitant PPI may influence tolerance. Further studies are needed to confirm these results.