Name of the Trial
Phase I/II Study of ABT-263 in Patients with Relapsed or Refractory T-cell or B-cell Lymphoid Malignancies (NCI-07-C-0006). See the protocol summary at http://cancer.gov/clinicaltrials/NCI-07-C-0006.

Principal Investigator
Dr. Wyndham Wilson, NCI Center for Cancer Research

Why This Trial Is Important
Lymphoid malignancies are cancers that originate in the body's lymphocytes (a type of white blood cell). A particular genetic mutation known as t(14;18) is frequently found in lymphoid cancers. This mutation causes a cell to produce too much of a protein called Bcl-2, which inhibits the process of programmed cell death (apoptosis) and contributes to tumor formation, tumor growth, and resistance to treatment.  

A new drug called ABT-263 may block the activity of Bcl-2, thereby allowing cancer cells that depend on this protein for survival to undergo apoptosis. Preclinical studies have shown that ABT-263 can bind to Bcl-2 in cancer cells and prevent it from functioning, leading to cell death.

In this clinical trial, patients with T-cell or B-cell lymphoid cancers that have recurred or progressed despite prior chemotherapy will receive ABT-263 orally for up to a year. Researchers seek to establish the maximum tolerated dose of ABT-263 and to determine the drug's safety and, preliminarily, its effectiveness in these patients. They will also study ABT-263's activity in the body (pharmacokinetics).

"The Bcl-2 protein family plays a crucial role in cancer cell immortalization in B-cell lymphomas, as well as in some T-cell lymphomas and solid tumors, making it an important molecular target for these cancers," said Dr. Wilson. "This is the first study in humans of ABT-263, which was specifically designed to inhibit Bcl-2."

Who Can Join This Trial
Researchers seek to enroll 80 patients aged 18 or over with a T-cell or B-cell lymphoid cancer that has relapsed or progressed despite previous chemotherapy. See the list of eligibility criteria at http://cancer.gov/clinicaltrials/NCI-07-C-0006.

Study Site and Contact Information
This study is taking place at the NIH Clinical Center in Bethesda, MD. For more information, call the NCI Clinical Trials Referral Office at 1-888-NCI-1937. The call is toll free and confidential.