Trial Information

Open Label Study of ONTAK (Denileukin Diftitox, DAB389 IL-2) to Estimate Response in Cutaneous T-Cell Lymphoma (CTCL) According to CD25 Status

Rationale: Some therapies for cancer target both healthy and diseased cells in the body.
Newer treatments have a more targeted approach that focus on tumor cells, including the drug
offered in this study called denileukin diftitox. This drug targets specific receptors on
malignant cells while minimizing damage to normal cells not expressing the receptor.
Denileukin Diftitox attaches to the cell surface of T-cell lymphocytes, which most commonly
cause skin lymphomas. Previous studies have demonstrated denileukin diftitox's ability to
kill certain leukemia and lymphoma cells due to the drug's ability to attach to the T-cell
lymphocytes and a protein called CD25. Some T-cell lymphocytes have the protein CD25 on
their cell surface, while others do not. CD25 helps to create an immune response. Denileukin
Diftitox is already approved for persistent or recurrent T-cell lymphoma with malignant
cells that express CD25. The current study will test denileukin diftitox in patients with
cutaneous T-cell lymphoma to gain information about treatment efficacy for patients who are
CD25 positive or CD25 negative.

Treatment: Patients in this study will receive denileukin diftitox. This drug will be
administered through intravenous infusions. Denileukin diftitox will be given for five
consecutive days. This schedule will be repeated every three weeks. Several tests and exams
will be conducted throughout the study, including imaging exams before each five day
treatment period with denileukin diftitox. Treatments will be discontinued due to disease
growth or unacceptable side effects. Patients responding to denileukin diftitox will
continue receiving the drug on the same schedule. Those with a complete response will
receive one additional five day treatment. All patients will be closely monitored.