Oseltamivir has been used to treat children with influenza for nearly two decades, with treatment currently approved for infants 2 weeks of age or older, but efficacy and safety remain controversial. Newer randomized placebo controlled trials (RCT), not included in previous meta-analyses, can add to the evidence base.

We conducted a systematic review to identify RCTs of oseltamivir therapy in children. We obtained individual patient data and examined protocol-defined outcomes. We then conducted a two-stage, random effects meta-analysis to determine the efficacy of treatment in reducing the duration of illness, estimated using differences in restricted mean survival time (RSMT) by treatment group. We also examined complications and safety.

We identified 5 trials including 2561 patients in the intent to treat (ITT) and 1598 in the intent to treat infected (ITTI) population. Overall, oseltamivir treatment significantly reduced the duration of illness in the ITTI population (RMST difference -17.6 hours 95% CI: -34.7 to -0.62 hours). In trials that enrolled patients without asthma, the difference was larger (-29.9 hours 95% CI -53.9 to -5.8 hours). Risk of otitis media was 34% lower in the ITTI population. Vomiting was the only adverse event with a significantly higher risk in the treatment group.

Despite substantial heterogeneity in pediatric trials, we found that treatment with oseltamivir significantly reduced the duration of illness in those with influenza and lowered the risk of developing otitis media. Alternative endpoints may be required to evaluate the efficacy of oseltamivir in pediatric patients with asthma.