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 a RCT on patients hospitalized for CAP (PTC trial) comparing 3-day versus 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). Choice of route and molecule was left to the physician in charge. The main outcome was failure at 15 days after first antibiotic intake, defined as temperature>37.9°C, and/or absence of resolution/improvement of respiratory symptoms, and/or additional antibiotic treatment for any cause. The primary outcome according to route of administration was evaluated through logistic regression. Inverse probability treatment weighting (IPTW) with a propensity score model was used to adjust for non-randomization of treatment route and potential confounders. The difference in failure rates was also evaluated among several sub-populations (AMC versus 3GC treatments, or intravenous versus 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. Failure rate at Day 15 was not significantly different among patients treated with initial intravenous versus oral treatment (25/93 (26.9%) versus 28/107 (26.2%), 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. Conclusions 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.