Safety and Efficacy Study of GC1008 to Treat Renal Cell Carcinoma or Malignant Melanoma

1 dose of 0.1 mg/kg IV followed by a 28 day observation period and then 3 additional doses of 0.1 mg/kg IV (one dose every 14 days)

1 dose of 0.3 mg/kg IV followed by a 28 day observation period and then 3 additional doses of 0.3 mg/kg IV (one dose every 14 days)

1 dose of 1.0 mg/kg IV followed by a 28 day observation period and then 3 additional doses of 1.0 mg/kg IV (one dose every 14 days)

1 dose of 3.0 mg/kg IV followed by a 28 day observation period and then 3 additional doses of 3.0 mg/kg IV (one dose every 14 days)

1 dose of 10.0 mg/kg IV followed by a 28 day observation period and then 3 additional doses of 10.0 mg/kg IV (one dose every 14 days)

1 dose of 15.0 mg/kg IV followed by a 28 day observation period and then 3 additional doses of 15.0 mg/kg IV (one dose every 14 days)

1 dose of 15.0 mg/kg IV followed by a 28 day observation period and then 3 additional doses of 15.0 mg/kg IV (one dose every 14 days)

1 dose of 15.0 or 10.0 mg/kg IV (based on safety profile of part 2, cohort 1) followed by a 28 day observation period and then 3 additional doses of 15.0 or 10.0 mg/kg IV (one dose every 14 days)