Name of the Trial
Phase I Study of Siplizumab (MEDI-507) in Patients with CD2-Positive Lymphoproliferative Disorders (NCI-04-C-0031). See the protocol summary at http://cancer.gov/clinicaltrials/NCI-04-C-0031.

Principal Investigator
Dr. John Edward Janik, NCI's CCR

Why Is This Trial Important?
Lymphoproliferative disorders, such as leukemias and lymphomas, are diseases in which cells of the lymphatic system (lymphocytes) grow excessively. These cancers can be especially hard to treat effectively if they arise from a malfunction in one type of lymphocyte called a T cell.

Siplizumab is a monoclonal antibody that binds to a protein called CD2, which is found abundantly on certain types of lymphocytes including T cells and Natural Killer (NK) cells. Initially developed to treat psoriasis, siplizumab has been shown in clinical studies to trigger T-cell death. This phase I dose-escalation study is investigating safety and tolerability, and will determine the maximum dose of siplizumab that can be given to patients with CD2-positive lymphoproliferative disease.

"Preclinical studies of siplizumab at NCI produced very promising results, with a short course of treatment yielding a 50 percent cure rate in mice with T-cell non-Hodgkin's lymphoma," said Dr. Janik. "Longer courses of treatment led to the treated mice living out their natural life spans.

"Early results from this trial have produced promising responses in some patients, and we hope to follow this research with additional studies combining siplizumab and chemotherapy," Dr. Janik added.

Who Can Join This Trial?
Researchers seek to enroll up to 24 additional patients aged 18 or older with CD2-positive lymphomas or leukemias that have been unresponsive to previous treatment. See the full list of eligibility criteria at http://cancer.gov/clinicaltrials/NCI-04-C-0031.

Where Is This Trial Taking Place?
This trial is being conducted at the NIH Clinical Center in Bethesda, Md.

Contact Information
For more information, call the NCI Clinical Studies Support Center (CSSC) at 1-888-NCI-1937. The call is toll free and completely confidential.