 The primary purpose of this protocol is to evaluate the safety and tolerability of intravenous peramivir, a neuraminidase inhibitor. Beginning with a low single-dose, the safety and tolerability is established by evaluating symptoms, clinical laboratory tests, ECG, and pharmacokinetics. Utilizing a series of stopping rules and a medical monitor, the dose will be escalated as safety and tolerability are established. Once the maximum tolerated dose MTD is established in the first part of this trial either limited by adverse effects or up to maximum anticipated dose, the safety and tolerability of multi-dose administration will begin replicating anticipated clinical use. These cohorts will be evaluated using similar criteria. The dose used in the multi-dose cohorts will also be escalated as safety and tolerability are established. 