Forgotten Leukemia Drug Shows Promise
Reported December 23, 2008
(Ivanhoe Newswire) — Doctors found a new weapon in the fight against an incurable form of leukemia, and it’s a drug that was once dismissed as ineffective in battling the disease.
Flavopiridol has shown promising results in phase I and II clinical trials that involved 116 patients with advanced chronic lymphocytic leukemia (CCL), according to researchers at The Ohio State University Comprehensive Cancer Center-James Cancer Hospital and Solove Research Institute.
Responses were seen in about half of the patients, many of whom had chromosomal abnormalities that made it unlikely that they would be helped by standard therapies. In recent years, treatment of CLL has improved, but the disease, which strikes 15,000 people each year and is the most common type of adult leukemia, remains incurable. Patients often suffer significant infections caused by the disease and treatment.
Flavopiridol showed promise as a potent cancer-fighter in the 1980s when it was tested on animals, but when it was given to humans in repeated trials, it proved ineffective and was essentially forgotten, researchers said.
Ohio State researchers said they later discovered that flavopiridol binds to proteins in human blood, which ties up much of the available drug and leaves less free drug in the bloodstream to kill cancer cells. So, in the earlier trials, humans were not getting enough of the drug for it to be effective.
The Ohio State researchers developed a new dosing schedule, and it increased the drug’s blood level enough to kill cancer cells in humans, they said.
“Flavopiridol has bridged the way for several CCL patients to receive a curative stem cell transplant,” said Dr. John Byrd, associate director of translational research and the principal investigator in the phase II trial.
The drug is now being tested at other cancer centers to see if similar results are reported, and at Ohio State, researchers are testing the drug’s effectiveness in battling acute myloid leukemia, non-Hodgkin’s lymphoma, Hodgkin’s lymphoma and head and neck cancers.
SOURCE: Study presented at the 50th Annual Meeting of the American Soceity of Hematology in San Francisco on Dec. 7, 2008
