Intravenous zanamivir was well-tolerated and associated with virologic response and clinical improvement in hospitalized children with influenza, according to the results of a study published in Pediatrics.
In this phase 2 open-label trial, 71 children hospitalized with influenza were enrolled to receive intravenous zanamivir (age- and weight-adjusted to provide a dose comparable to 600 mg twice-daily in adults) for 5 to 10 days. The primary outcomes were treatment-emergent adverse events, clinical laboratory measurements, and vital signs. Secondary outcomes included clinical outcomes, pharmacokinetics, and virologic efficacy data.
Treatment-emergent adverse events were reported in 72% of patients, and serious treatment-emergent adverse events occurred in 21% of patients. The mortality rate was 7%. Serious treatment-emergent adverse events and deaths were not considered to be related to zanamivir treatment.
Pharmacokinetic analyses revealed that the mean zanamivir exposures in patients with normal renal function (n = 34) ranged from 64.5 to 110 hour·μg/mL.
After 2 days of treatment, viral load decreased by a median of 1.81 log10 copies/mL from baseline.
The study authors concluded that “the safety profile of [intravenous] zanamivir was consistent with that expected in children with severe influenza, with no newly identified drug-related adverse safety findings.”
Bradley J, Blumer JL, Romero JR, et al. Intravenous zanamivir in hospitalized patients with influenza. Pediatrics. 2017;140(5):e20162727.