Zanamivir for Treatment of Symptomatic Influenza A and B Infection in Children Five to Twelve Years of Age: A Randomized Controlled Trial

Pediatr Infect Dis J. 2000 May;19(5):410-7. doi: 10.1097/00006454-200005000-00005.


Background: Influenza infection rates are higher in children than in other age groups. This study evaluated the efficacy, safety and tolerability of a 5-day course of twice daily inhaled zanamivir, 10 mg, compared with placebo in the treatment of symptomatic influenza A and B viral infections among children 5 to 12 years of age.

Methods: This double blind, randomized, placebo-controlled, parallel group, multicenter study conducted in the Northern Hemisphere during the 1998 and 1999 influenza season enrolled 471 patients with influenza-like symptoms for < or = 36 h. Patients were randomly assigned to zanamivir (n = 224) or placebo (n = 247). Symptoms were recorded on diary cards twice daily during treatment, for 9 days after treatment and for 14 additional days (if still reporting moderate/severe cough and/or taking relief medication).

Findings: A total of 346 (73%) patients were influenza-positive by culture, serology or polymerase chain reaction (65% influenza A, 35% influenza B). Zanamivir reduced the median time to symptom alleviation by 1.25 days compared with placebo among patients with confirmed influenza infection (P < 0.001). Zanamivir-treated patients returned to normal activities significantly faster and took significantly fewer relief medications than placebo-treated patients. Zanamivir was well-tolerated, demonstrating adverse event profiles similar to those of placebo and no clinically significant changes in laboratory findings. Viral susceptibility testing revealed no zanamivir-resistant strains of influenza A or B.

Conclusions: Zanamivir was effective in shortening the duration and severity of influenza symptoms and was well-tolerated among children 5 to 12 years of age.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Inhalation
  • Antiviral Agents / administration & dosage
  • Antiviral Agents / adverse effects
  • Antiviral Agents / therapeutic use*
  • Child
  • Child, Preschool
  • Double-Blind Method
  • Female
  • Guanidines
  • Humans
  • Influenza A virus / drug effects
  • Influenza A virus / isolation & purification*
  • Influenza B virus / drug effects
  • Influenza B virus / isolation & purification*
  • Influenza, Human / drug therapy*
  • Influenza, Human / virology
  • Male
  • Patient Compliance / statistics & numerical data
  • Pyrans
  • Sialic Acids / administration & dosage
  • Sialic Acids / adverse effects
  • Sialic Acids / therapeutic use*
  • Treatment Outcome
  • Zanamivir


  • Antiviral Agents
  • Guanidines
  • Pyrans
  • Sialic Acids
  • Zanamivir