Antibiotic Treatment Within a Year of ICI Therapy May Result in Worse Survival Outcomes
Source: Onc Nursing News, March 2023
A retrospective cohort demonstrated that patients who are treated with antibiotics within 1 year before immune checkpoint inhibitor therapy may experience worse overall survival.
Findings from a population-level retrospective cohort study published in the Journal of Clinical Oncology demonstrated that patients with cancer who are treated with antibiotics within 1 year before immune checkpoint inhibitor (ICI) therapy may experience worse overall survival (OS) outcomes due to alteration in the gut microbiome. Antibiotic class analysis concluded that fluoroquinolones given within 1 year or 60 days before an ICI were associated with worse OS and a dose effect was observed; patients receiving anti–PD-1 ICIs and those with lung cancer or melanoma also experienced poorer OS.
Overall, the median OS was 302 days for patients (n = 2737) in the final cohort. Comparatively, patients who received antibiotics 1 year prior to beginning therapy with an ICI (n = 1627) had a worse OS with an adjusted HR (aHR) of 1.12 (95% CI, 1.01-1.24; P = .03). Investigators noted that “associations were significant for any antibiotic exposure within 1 year of starting ICIs, while a nonsignificant trend was seen for 60 days, and no significant associations were seen for exposure within 30 days.”