During the 2009 swine influenza pandemic, the FDA briefly authorized the emergency use of peramivir, an investigational NI that is administered intravenously [64] . In one study, a single dose of 300 mg or 600 mg of IV peramivir significantly reduced the time to alleviation of symptoms compared with placebo (HR 0.68 and 0.67 for the 300 mg and 600 mg doses respectively) [65] . Laninamivir octanoate, another long acting NI in development, was non-inferior to a five-day course of oral oseltamivir in adults with seasonal influenza in one study [66] . Experience with avian influenza H5N1, which has caused sporadic cases since 2004 with an elevated mortality rate, is much more limited and recommendations for its treatment are in most cases extrapolated from trials of seasonal influenza. There are, however, reports that suggest reduced severity and mortality with the administration of oseltamivir in patients with avian influenza [67] [68] [69] . In patients with pneumonia or with clinical failure to standard regime with oseltamivir, a higher dose of 150 mg bid for 10 days should be considered [24, 67] . In regions with adamantine-susceptible strains, combination therapy with a NI and an adamantine may also be considered with pneumonia or clinical worsening [24] . Therapy with oseltamivir should be administered even in the late course of influenza A (H5N1) infection since viral replication is more prolonged than with seasonal influenza [24] .