Green Tea May Help Fight Leukemia

June 01, 2009

Researchers from the Mayo Clinic in Rochester, MN and the Ernest Mario School of Pharmacy at Rutgers in Piscataway, NJ report good results in early leukemia clinical trials using EGCG; the major active ingredient in Green Tea. The trial determined that patients with chronic lymphocytic leukemia (CLL) can tolerate the Green Tea constituent when high doses are taken in capsule form and that the lymphocyte count was reduced in one-third of the patients. “We found not only that patients tolerated the green tea extract at very high doses, but that many of them saw regression to some degree of their chronic lymphocytic leukemia,” says Tait Shanafelt, M.D., Mayo Clinic hematologist and lead author of the study. “The majority of individuals who entered the study with enlarged lymph nodes saw a 50 percent or greater decline in their lymph node size.”

CLL is the most common type of leukemia in the United States. Currently it has no cure. Blood tests have enabled early diagnosis in many instances; however, treatment consists of watchful waiting until the disease progresses. Statistics show that about half of patients with early stage diseases have an aggressive form of CLL that leads to early death. Researchers hope that EGCG can stabilize CLL for early stage patients or perhaps improve the effectiveness of treatment when combined with other therapies.

The research has moved to the second phase of clinical testing in a follow-up trial -- already fully enrolled -- involving roughly the same number of patients. All will receive the highest dose administered from the previous trial.

In the first clinical trial designed to find the best dosage of EGCG, 33 patients received variations of eight different oral doses of a proprietary compound whose primary active ingredient is EGCG. Doses ranged from 400 milligrams (mg) to 2,000 mg administered twice a day. Researchers determined that they had not reached a maximum tolerated dose, even at 2,000 mg twice per day.

92% of the patients with swollen lymph nodes experiencing at least a 50% reduction in the swelling. 33% of the patients have a sustained reduction in absolute lymphocyte count of at least 20%. The findings appear online ahead of print in the May 26, 2009 edition of the Journal of Clinical Oncology.