Oral oseltamivir in human experimental influenza B infection

Antivir Ther. 2000 Sep;5(3):205-13.


Oseltamivir is the prodrug of Ro64-0802 (GS4071), a potent and selective inhibitor of influenza A and B virus neuraminidases. Three randomized, double-blind, placebo-controlled, parallel-group studies evaluated oral oseltamivir for early treatment (75 or 150 mg twice daily for 5 days) or prevention (75 mg once or twice daily for 7 days) of experimental influenza B virus infection in healthy susceptible adults. Treatment study A (n=60) demonstrated similar trends to treatment study B (n=117), in which 75 mg doses of oseltamivir introduced 24 h after inoculation reduced median area under curve (AUC) virus titre (oseltamivir, 22.7; placebo, 131.1 log10 TCID50 x h/ml; P=0.002) and duration of viral shedding (oseltamivir, 23.9 h; placebo, 95.8 h; P=0.0005). In prevention study C (n=58), oseltamivir did not reduce infection rates (85 versus 84%) but significantly reduced median AUC virus titre (10.0 versus 66.9 log10 TCID50 x h/ml; P=0.03) and duration of viral shedding (36 versus 84 h; P=0.03) compared with placebo. Oseltamivir was well tolerated. No emergence of drug-resistant variants was detected by testing last-day isolates (n=112) in neuraminidase inhibition assays. These results indicate that oseltamivir has significant antiviral activity in experimental human influenza B virus infection when used for prophylaxis or early treatment.

Publication types

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

MeSH terms

  • Acetamides / therapeutic use*
  • Adolescent
  • Adult
  • Antiviral Agents / therapeutic use*
  • Double-Blind Method
  • Humans
  • Influenza B virus* / isolation & purification
  • Influenza B virus* / pathogenicity
  • Influenza, Human / drug therapy*
  • Influenza, Human / prevention & control*
  • Influenza, Human / virology
  • Middle Aged
  • Oseltamivir


  • Acetamides
  • Antiviral Agents
  • Oseltamivir