Immune checkpoint inhibitors (ICIs) have been approved as first-line therapy for advanced non-small cell lung cancer (NSCLC). The probiotic MIYAIRI 588 can potentially improve the outcomes of patients with advanced NSCLC treated with ICI. However, the impact of other probiotics on ICI-treatment efficacy remains unclear. Thus, we aimed to clarify the association between BIO-three use and treatment outcomes in patients with advanced NSCLC treated with ICI.
This retrospective study included patients aged ≥ 18 years with advanced or recurrent NSCLC who had received ICI monotherapy or ICI plus chemotherapy. Concomitant therapy with probiotic bacteria was defined as receiving it within 180 days before ICI therapy.
Here, 289 patients were enrolled, including 23 (8.0%) receiving BIO-three. In the multivariable analysis, the progression-free survival (PFS) and overall survival (OS) of patients receiving BIO-three tended to be longer than those of patients not receiving probiotic therapy (PFS, hazard ratio [HR] 0.75; 95% confidence interval [CI] 0.43-1.30; p = 0.33; OS, HR 0.69; 95% CI 0.37-1.28; p = 0.24). After propensity score matching with weighted adjustment, patients receiving BIO-three tended to have prolonged PFS (median PFS [range] 7.6 months [2.6-17.4] vs 3.2 months [1.6-7.0]; HR 0.53; 95% CI 0.25-1.12; p = 0.09) and OS (median OS [range] 25.6 months [10.8-not reached] vs 10.9 months [7.3-not reached]; HR 0.57; 95% CI 0.24-1.36; p = 0.20) than those not receiving probiotic therapy.
This study suggests the prognostic impact of concomitant BIO-three use in patients with advanced NSCLC on ICI treatment.

© 2024. The Author(s) under exclusive licence to Japan Society of Clinical Oncology.