Does Antibiotic Therapy Impact Outcomes to Chemoimmunotherapy in NSCLC?
Posted: Monday, August 30, 2021
Alessio Cortellini, MD, and David James Pinato, MD, PhD, both of the Imperial College London, as well as international colleagues, studied the effect of antibiotic therapy on patients with non–small cell lung cancer (NSCLC) who were undergoing chemoimmunotherapy. These investigators found that antibiotic therapy, both prior and concurrent, appears to be safe in most of these patients and does not seem to impair clinical outcomes. Their results, published in Annals of Oncology, also suggest that patients who are PD-L1–positive may be best served by combinations of chemoimmunotherapy to avoid the adverse effects of prior antibiotics, which are increasingly known to impair the efficacy of single-agent immune checkpoint inhibitors.
This retrospective study focused on the data of 302 patients with stage IV NSCLC who were treated with first-line chemoimmunotherapy and either prior or concurrent antibiotic therapy. The most common antibiotic classes were beta-lactams (40.4%) and cephalosporins (21.3%). Progression-free survival and overall survival were followed until either disease progression or death.
A total of 47 patients underwent previous antibiotic therapy, and 117 received concurrent therapy. Former smokers made up most (71.5%) of the population, with 61 individuals (20.2%) identifying as former or current smokers. Of 274 evaluable patients, 76 had 50% or higher PD-L1 tumor expression, 84 had 1% to 49% PD-L1 expression, and 113 had less than 1% PD-L1 expression.
According to multivariable analysis, overall survival (hazard ratio [HR] = 1.42) and progression-free survival (HR = 1.12) were comparable among patients who did and did not receive prior antibiotic therapy. This trend was similar for the overall response rate across exposed and unexposed patients (42.6% vs. 57.4%), and it was not considered to be statistically significant (P = .1794). Of note, patients who underwent concurrent antibiotic therapy also had similar progression-free (HR = 1.29) and overall (HR = 1.30) survival to those who did not. Among patients who received previous antibiotics, there appeared to be no significant differences in progression-free or overall survival when accounting for the duration of exposure (< 7 vs. ≥ 7 days) or the type of administration (oral vs. intravenous).
Disclosure: For full disclosures of the study authors, visit annalsofoncology.org.
