Study of Interleukin-21 for Metastatic Malignant Melanoma and Metastatic Kidney Cancer

This is a phase 1 safety study. Everyone enrolled and eligible will be given rIL-21. The study has 2 parts, Part A will determine how high a dose of rIl-21 can be safely given to patients with these types of cancers. Part B will determine if the drug is of any benefit to patients with these types of cancers. Part A may have up to 7 different dose groups. Beginning with the lowest dose, 3 patients will be treated and will be watched for side effects. If the side effects are not severe, the next group of 3 patients will recieve a higher dose. This cycle is repeated until the highest tolerated dose group is found.