Introduction: Laninamivir octanoate inhalation powder is a treatment for influenza. Given that inhalation powder administration is difficult for some patients, a new formulation of laninamivir octanoate administered via a nebulizer inhaler was developed. This study evaluated the superiority and safety of a single inhaled dose of laninamivir octanoate using a nebulized inhaler versus placebo.

Methods: This randomized, single-blind, placebo-controlled, parallel-group, multicenter phase 3 study included patients aged ≥10 years with confirmed influenza A or B virus infection. Patients were randomized 1 : 1 to receive a single inhaled dose of laninamivir octanoate 160 mg inhalation solution (nebulizer inhaler) or placebo. The primary endpoint was influenza duration; the secondary endpoint was the time from the end of the Day 1 study visit to the first timepoint at which the patient’s body temperature was ≤36.9°C for at least 21.5 hr. Adverse events (AEs) were monitored for safety.

Results: In total, 534 patients were randomized. Median influenza duration was 55.3 hr (95% confidence interval [CI] 48.9, 68.8) and 73.6 hr (95% CI 67.8, 84.3) in the laninamivir octanoate and placebo groups, respectively (difference -18.3 hr [95% CI -23.6, -3.8]; P = 0.0048). Median time for body temperature to return to normal was 36.4 hr (95% CI 33.0, 41.3) and 51.4 hr, respectively (95% CI 45.7, 57.8; difference −15.0 hr [95% CI -18.6, -7.9]). No serious AEs, AEs leading to discontinuation, or deaths were reported.

Conclusions: In patients aged ≥10 years, laninamivir octanoate 160 mg nebulizer inhaler was effective against influenza A or B virus infection.

Introduction: A formulation of laninamivir octanoate that is administered using a nebulizer was developed to facilitate drug delivery in patients who have difficulty using powder inhalers, including young children. This study evaluated the efficacy and safety of this new formulation of laninamivir octanoate in pediatric patients with influenza infection.

Methods: This multicenter, uncontrolled, open-label phase 3 study enrolled Japanese pediatric patients aged <10 years with influenza virus A or B infection. Patients were treated with a single inhalation dose of laninamivir octanoate administered using a nebulizer. The primary endpoint was duration of influenza; the secondary endpoint was time to recovery of a normal body temperature (≤37.4°C). Adverse events (AEs) were assessed for safety.

Results: In total, 173 patients were enrolled and treated with laninamivir octanoate. The median (95% confidence interval [CI]) influenza duration (primary endpoint) was 49.0 hr (43.0, 61.0). The median (95% CI) time to recovery of a body temperature ≤37.4°C (secondary endpoint) was 31.1 hr (25.8, 33.7). Thirty-five patients (20.2%) experienced AEs, and one AE of nausea during inhalation resulted in treatment discontinuation. There were no deaths or serious AEs reported.

Conclusions: In this first clinical trial to evaluate a nebulizer formulation in pediatric patients (aged <10 years) with influenza, it was suggested that a single dose of laninamivir octanoate 160 mg administered using a nebulizer was safe and well tolerated in these patients.