Exclusive oral antibiotic treatment for hospitalized community-acquired pneumonia: a post-hoc analysis of a randomized clinical trial

Objectives: In this study, we aimed to assess the efficacy of different ways of administration and types of beta-lactams for hospitalized community-acquired pneumonia (CAP). Methods: In this post-hoc analysis of randomized controlled trials (RCT) on patients hospitalized for CAP (pneumonia short treatment trial) comparing 3-day vs. 8-day durations of beta-lactams, which concluded to non-inferiority, we included patients who received either amoxicillin-clavulanate (AMC) or third-generation cephalosporin (3GC) regimens, and exclusively either intravenous or oral treatment for the first 3 days (followed by either 5 days of oral placebo or AMC according to randomization). The choice of route and molecule was left to the physician in charge. The main outcome was a failure at 15 days after the first antibiotic intake, defined as temperature >37.9 degrees C, and/or absence of resolution/improvement of respiratory symptoms, and/or additional antibiotic treatment for any cause. The primary outcome according to the route of administration was evaluated through logistic regression. Inverse probability treatment weighting with a propensity score model was used to adjust for non-randomization of treatment routes and potential confounders. The difference in failure rates was also evaluated among several sub-populations (AMC vs. 3GC treatments, intravenous vs. oral AMC, patients with multi-lobar infection, patients aged >= 65 years old, and patients with CURB65 scores of 3-4). Results: We included 200 patients from the original trial, with 93/200 (46.5%) patients only treated with intravenous treatment and 107/200 (53.5%) patients only treated with oral therapy. The failure rate at Day 15 was not significantly different among patients treated with initial intravenous vs. oral treatment [25/93 (26.9%) vs. 28/107 (26.2%), adjusted odds ratios (aOR) 0.973 (95% CI 0.519-1.823), p 0.932)]. Failure rates at Day 15 were not significantly different among the subgroup populations. Discussion: Among hospitalized patients with CAP, there was no significant difference in efficacy between initial intravenous and exclusive oral treatment. Trial registration: This trial is registered with ClinicalTrials.gov, NCT01963442.