There will be 15 patients entered (with the goal of 12 evaluable patients) distributed among two treatment groups. Patients will be randomized at a 3 to 1 ratio between h5G1.1-mAb and placebo. Following a screening period of no less than 7 days, a 2 month double-blind, randomized treatment period will commence. Patients will receive an active (h5G1.1-mAb, 8mg/kg) bolus infusion every week X 5, then every 2 weeks X 2, or a placebo bolus infusion every week X 5, then every 2 weeks X 2. All patients will be receiving 7 infusions of h5G1.1-mAb or placebo.