Used to prevent influenza-related hospitalization or death, inhaled zanamivir was not inferior to oral oseltamivir in ambulatory patients in Taiwan who did not require hospitalization within 2 days, researchers report. The nationwide, population-based, cohort study included all outpatients treated with inhaled zanamivir or oral oseltamivir within 48 hours after a clinical diagnosis of influenza before and after the rollout of inhaled zanamivir as a first-line antiviral agent in this country.
The primary outcome was influenza-related hospitalization or death within 14 days, but those developing this outcome within 2 days were excluded from the analysis. Study results showed the following: “A total of 865,032 eligible influenza outpatients were included in the analysis. The risk of developing the main outcome (adjusted hazard ratio [aHR], 1.01; 95% confidence interval [CI], .96 to 1.06) did not differ between the inhaled zanamivir group (n = 595,897, 68.9%, the reference) and the oral oseltamivir group (n = 269,135, 31.1%). Prespecified analysis on high-risk subgroups further showed that inhaled zanamivir is not inferior to oral oseltamivir in either patients aged ≥65 years (aHR, 1.14; 95% CI: 1.05 to 1.25) or patients with chronic lung diseases (aHR, 1.23; 95% CI: 1.08 to 1.41).”