Oral Oseltamivir Improves Pulmonary Function and Reduces Exacerbation Frequency for Influenza-Infected Children With Asthma.

Johnston SL, Ferrero F, Garcia ML, Dutkowski R.

From the *Department of Respiratory Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom; daggerHospital de Ninos Pedro de Elizalde, Docencia e Investigacion, Buenos Aires, Argentina; double daggerHospital Severo Ochoa, Neumologia Infantil, Madrid, Spain; and section signF. Hoffmann-La Roche, Nutley, NJ.

BACKGROUND:: Among asthmatic children, influenza is associated with increased hospitalizations. Although vaccination is safe and effective among asthmatic children, its protective efficacy varies and uptake rates can be low. In comparison, oseltamivir (Tamiflu) is effective against all influenza strains and can reduce the severity and duration of influenza among adults and children. This study determined the effects of oseltamivir among influenza-infected children with asthma. METHODS:: Asthmatic children (6-12 years of age) were randomized to receive oseltamivir (2 mg/kg) or placebo twice daily, as a syrup. The primary efficacy endpoint was the time to freedom from illness. Secondary endpoints included the area under the symptom score-hour curve, the proportion of patients with asthma exacerbations and changes in forced expiratory volume at 1 second during the dosing period. Analysis was performed for both the intent-to-treat infected (n = 179) and per protocol (n = 162) populations. RESULTS:: The primary endpoint for this study was not met. Oseltamivir tended to reduce the time to freedom from illness in the intent-to-treat infected population (10.4 hours, 8%; P = 0.5420), the per protocol population (24.3 hours, 17%; P = 0.1607) and patients who started treatment <24 hours after symptom onset (39.8 hours, 25%; P = 0.0780). However, an improvement in pulmonary function was observed. The improvement in forced expiratory volume at 1 second was significantly greater among oseltamivir-treated patients (10.8% versus 4.7%; P = 0.0148). Oseltamivir-treated patients also experienced fewer asthma exacerbations up to day 7 (68% versus 51%; P = 0.031). Oseltamivir was safe and well-tolerated. CONCLUSIONS:: Oseltamivir is safe and well-tolerated among asthmatic children, may reduce symptom duration and helps improve lung function and reduce asthma exacerbations during influenza infection.