relative merits of zanamivir and oseltamivir

There is an informative article on the relative merits of zanamivir (Relenza) and oseltamivir (Tamiflu). It is in Journal of Medical Virology 79:1577–1586 (2007) "Neuraminidase Inhibitor Resistance in
Influenza Viruses" by P.A. Reece.

QUOTE
In the case of influenza A(H5N1) human infections, the WHO and others have noted that if emergence and spread of viruses resistant to oseltamivir were to occur, it would have significant implications for the prevention and control of potential pandemic influenza [WHO, 2005a]. Calls to add zanamivir to government stockpiles [Moscona, 2005a; The Royal Society, 2006] have been prompted partly by the knowledge that, to date, oseltamivir resistant H5N1 virus remains sensitive to zanamivir. Zanamivir’s in vitro efficacy against H5N1 strains including oseltamivir resistant strains, its efficacy and safety, and its pharmacokinetic profile, support its use for treatment and prophylaxis of H5N1 infections in humans [Tsang et al., 2005]. Intravenously administered zanamivir is efficacious in the human challenge model of influenza [Calfee et al., 1999] and may be a useful adjunct in seriously ill patients, but is currently not a regulatory approved formulation of the drug.
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