Confirmation of the negative impact of antibiotics on immuno-oncology patients’ survival
Da Volterra is presenting new data at the Society for Immunotherapy of Cancer’s (SITC) 2020 Virtual Meeting this week under the title “Update of a Systematic Review and Meta-Analysis Studying the Association Between Antibiotic Use and Clinical Outcomes of Non-Small-Cell Lung Cancer Patients Treated with Immune Checkpoint Inhibitors”.
Da Volterra’s team conducted a systematic review of literature and analyzed data from 22 studies for Progression-Free Survival (PFS) and 27 studies for Overall Survival (OS). Overall, 3,471 and 6,376 patients diagnosed with Non-Small-Cell Lung Cancer (NSCLC) were included in the update for PFS and for OS, respectively.
The study demonstrates that exposure to antibiotics around the initiation of Immune Checkpoint Inhibitor (ICI) treatment reduces the survival of NSCLC patients which is hypothesized to be due to a decreased efficacy of ICIs when the gut microbiota is disrupted. The pooled hazard ratio calculated, taking into account the latest available data in the field, was 1.55 (95% confidence interval [CI]: 1.27–1.90) for PFS and 1.73 (95% CI: 1.38–2.17) for OS, demonstrating a statistically significant impact. The impact of antibiotics depended on the timeframe of their administration with respect to ICIs treatment initiation: the strongest effect was reported for limited time windows shortly before and after ICIs treatment initiation (from 90 days before to 60 days after treatment start).
When taken together with recent studies by Jin et al. and Gopalakrishnan et al. showing a correlation between a low-diversity microbiota and a reduced survival of cancer patients treated with ICIs, the meta-analysis further suggests that the intestinal microbiota may be a predictor and modulator of the response to ICIs. However, it is only with more robust clinical data that the medical community will be able to proffer the best recommendations regarding antibiotic use for cancer patients treated with ICIs.
Poster available here.