Group A: Six to 12 subjects will be treated with transfectoma-derived MDX-010 at 2.8 or 5 mg/kg/dose, or with hybridoma-derived MDX-010 at 3 mg/kg/dose administered on Days 1, 57, and 85. The 2.8, 3, and 5 mg/kg dosage cohorts may be initiated concurrently. Additionally, 6 subjects per cohort will receive single doses of transfectoma-derived MDX-010 at 7.5, 10, 15, and 20 mg/kg.