Phase II Evaluation of RFT5-dgA in Patients With Metastatic Melanoma

Background:

• CD4+ cells are white blood cells that regulate the immune system by controlling the strength and quality of the immune response.
• CD25+ cells are a subset of CD4+ cells that suppress or prevent immune responses.
• RFT-5-dgA is an immunotoxin (substance that kills specific cells in the immune system) that kills CD25+ cells.
• In mouse studies, RFT-5-dgA showed anti-tumor activity in animals studies.

Objective: To determine whether the immune system of patients with metastatic melanoma (melanoma that has spread beyond the original site) can cause tumors to shrink if the patients are given RFT-5-dgA to remove their CD25+ cells.

Eligibility: Patients 18 years of age and older with metastatic melanoma whose disease has progressed after receiving standard treatment.

Design:

• Patients receive RFT-5-dgA through a vein every other day for a total of 3 doses (one treatment course). Patients have routine blood tests during the week of treatment.
• Four to 5 weeks after the last dose, patients are evaluated with a physical examination, blood tests and scans and x-rays to evaluate their tumor.
• Patients whose tumor has shrunk or remained stable may be offered additional treatment with RFT-5-dgA up to a total of four courses.
• Patients undergo leukapheresis or have several tubes of blood drawn from a vein to determine the effects of RFT-5-dgA on the immune system. This is done before the first dose of RFT-5-dgA, after the first three doses, and possibly during subsequent treatment courses in those patients who receive additional treatment. For leukapheresis, blood is collected through a needle in an arm vein and flows through a catheter into a machine that separates it into its components by spinning. The white cells are extracted and the rest of the blood is returned through another needle in the other arm.