Da Volterra is presenting new data at the European Society for Medical Oncology (ESMO) Immuno-Oncology 2020 Virtual Meeting this week under the title “Update of Systematic Reviews and Meta-Analyses Studying the Association Between Antibiotic Use and Clinical Outcomes of Cancer Patients Treated with Immune Checkpoint Inhibitors”.
Da Volterra’s team conducted a systematic review of literature and analyzed data from 45 studies for Progression-Free Survival (PFS) and 65 studies for Overall Survival (OS). Overall, 14,689 and 23,146 patients diagnosed with several types of cancers such as non-small-cell lung cancer (NSCLC), melanoma, renal cell cancer, urothelial carcinoma, and other types were included in the update for PFS and for OS, respectively.
The study demonstrates that exposure to antibiotics around the initiation of the immune checkpoint inhibitor (ICI) treatment reduces the survival of cancer 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 1.44 (95% confidence interval [CI]: 1.27–1.64) for PFS and 1.65 (95% CI: 1.46–1.87) for OS, demonstrating a statistically significant impact. The negative impact of antibiotics on patients’ survival was demonstrated in most types of cancers, with a particularly significant effect in NSCLC and melanoma cancers. The impact of antibiotics depended on the timeframe of their administration with respect to ICI treatment initiation: the strongest effect was reported for limited time windows shortly before and after ICI treatment initiation (from 60 days before to 30 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
Link towards the scientific news on the ESMO website.