Health experts believe that green tea has a protective effect on a number of chronic diseases, including heart disease, stroke, and certain cancers. Now, new data resulting from a phase 2 clinical trial has revealed that green tea extracts may have some clinical benefits in the treatment of chronic lymphocytic leukemia (CLL).

The extract in question is called epigallocatechin gallate (EGCG), which is a major component of green tea, and has been found to reduce the number of cancer cells in patients suffering from CLL. Previous work with EGCG in the laboratory had shown that the compound was effective against leukemia cells in culture, and these results were followed by the successful use of EGCG in phase 1 clinical trials.

This represented the first time that green tea extracts had been studied in patients. EGCG is part of a growing trend in medicine known as neutraceuticals, which are food or food products that provide potential health or medical benefits, much like a drug.

Neutraceuticals also have the added advantage of being naturally derived and as a consequence, less toxic that synthetic drugs and chemicals. However, experts stress that they are not necessarily a substitute for more stringent approaches to therapy like chemotherapy.

In fact, the patients were given EGCG at a time when their diseases were asymptomatic and would not have otherwise been treated unless the conditions progressed. Furthermore, the use of GECG did not show substantial repression of CLL, though the clinical activity suggests that it may be useful as a way to help stabilize and slow down the progression of the disease.

In the study in question, doctors used the information from the previous trial to design their current approach. Using the highest dose tested, they enrolled a total of 42 patients (41 completed the study) and found that 31 percent of them experienced a 20 percent reduction in leukemia cell counts in their blood. Doctors also saw a reduction in lymph node sizes of up to one half or more in 69 percent of the patients with enlarged glands.

Researchers were also vigilant in keeping track of side effects, mainly because the patients in question were not in advanced stages of the disease. While most trials only look at grade 3 or higher side effects, they included grade 1 and 2 side effects in their analysis. With this in mind, several of the patients experienced some degree of grade 1 or 2 side effects, but only three of the 42 had grade 3 side effects over the course of the study, indicating the treatment was well tolerated.

The authors stress, however, that without phase 3 clinical trials, they cannot at this time make firm recommendations about the use of EGCG in patients with CLL. Those individuals who want to take supplements of EGCG should only do so with under the supervision of their physicians.

If you have questions or concerns about CLL, speak with your doctor or visit the website for the National Cancer Institute. For more information about EGCG, visit the website for the American Cancer Society.