Oseltamivir, zanamivir and amantadine in the prevention of influenza: a systematic review.
OBJECTIVE
To systematically review evidence relating to the clinical efficacy of oseltamivir, zanamivir and amantadine in the prevention of influenza.


METHODS
RCTs evaluating these interventions in seasonal prophylaxis and post-exposure prophylaxis were identified using electronic bibliographic databases and handsearching of retrieved articles.


RESULTS
Oseltamivir was effective in preventing symptomatic laboratory-confirmed influenza (SLCI) in seasonal prophylaxis in healthy adults and at-risk elderly subjects and in post-exposure prophylaxis within households of mixed composition. Post-exposure prophylaxis using oseltamivir for paediatric contacts was observed to prevent SLCI. Zanamivir prevented SLCI in seasonal prophylaxis in healthy adults, at-risk adults and adolescents and in post-exposure prophylaxis within mixed households, with a trend for seasonal and post-exposure preventative effects in elderly subjects. Evidence for amantadine prophylaxis across subgroups was very limited. However, amantadine prevented SLCI in seasonal prophylaxis in healthy adults and in outbreak control amongst adolescent subjects. Interventions were reported to be well tolerated by subjects, with a relatively low proportion of subjects experiencing drug-related adverse events and drug-related withdrawals.


CONCLUSIONS
Evidence was identified for the efficacy of oseltamivir and zanamivir in preventing influenza in a range of population subgroups. The evidence base for amantadine was considerably more limited.
Health Economics and Decision Science, School of Health and Related Research, University of Sheffield, Regent Court, 30 Regent Street, Sheffield, UK. R.Jackson@Sheffield.ac.uk
Rachel J
RJ
Jackson
Katy L
KL
Cooper
Paul
P
Tappenden
Angie
A
Rees
Emma L
EL
Simpson
Robert C
RC
Read
Karl G
KG
Nicholson
D000547:Amantadine / Q000627:therapeutic use*; D000998:Antiviral Agents / Q000627:therapeutic use*; D004196:Disease Outbreaks / Q000517:prevention & control; D006801:Humans; D007252:Influenza Vaccines; D007251:Influenza, Human / Q000517:prevention & control*; D009439:Neuraminidase / Q000037:antagonists & inhibitors; D053139:Oseltamivir / Q000627:therapeutic use*; D056990:Post-Exposure Prophylaxis; D016896:Treatment Outcome; D014763:Viral Matrix Proteins / Q000037:antagonists & inhibitors; D053243:Zanamivir / Q000627:therapeutic use*; D000086082:Viroporin Proteins
D000547:Amantadine; D000998:Antiviral Agents; D007252:Influenza Vaccines; D009439:Neuraminidase; D053139:Oseltamivir; D014763:Viral Matrix Proteins; D053243:Zanamivir; C488937:M2 protein, Influenza A virus; D000086082:Viroporin Proteins