June 30, 2008
Flurizan, an experimental drug that had been undergoing late-stage testing, failed to show benefits for easing the memory loss and thinking problems of Alzheimer's disease.
The findings are very disappointing because Flurizan was one of a new class of Alzheimer's medications that work in a new way. Unlike existing Alzheimer's drugs like Aricept, Exelon and Namenda, which may ease symptoms but do not stop the downward progression of disease, Flurizan was aimed at underlying disease processes and sought to modify the course of Alzheimer's.
"We are disappointed that Flurizan failed to achieve significance in this study, and we will now discontinue development of this compound," said Peter Meldrum, President and Chief Executive Officer of Myriad Genetics, the company that makes the drug.
Flurizan is aimed at beta-amyloid, the toxic protein that builds up and forms plaques in the brains of those with Alzheimer's. Researchers were hoping that it might offer a new avenue of attack for stemming the decline of dementia. But the drug, which goes by the generic name tarfenflurbil, did not improve thinking and memory skills or the ability to carry out everyday tasks compared to a placebo.
The drug had shown promise in mid-stage trials in Britain earlier this spring. [See the article, "Experimental Drug Flurizan May Slow Decline of Mild Alzheimer's"] The most recent trial was larger, involving some 1,700 men and women with mild Alzheimer's disease who were given the drug over 18 months.
Most scientists believe that beta-amyloid causes the major symptoms of Alzheimer's. The failure of Flurzan does not, in the opinion of Fisher Center scientists, cast doubt on that hypothesis. However, the latest testing failure does underscore the need to carry on research aimed at answering fundamental questions about Alzheimer's and what the best therapeutic targets are, a goal that will eventually lead to a cure.
Other companies are testing different drugs in late-stage testing. Wyeth and Elan, for example, are testing a drug called bapineuzumab. The drug is what's called a monoclonal antibody, an immune-system protein that clears toxic beta-amyloid from the brain in a different way than Flurizan. Dozens more drugs are in development.
It may take years of additional research to find a medication that is safe and effective and that may halt, or even reverse, Alzheimer's. The Fisher Center for Alzheimer's Research Foundation continues to fund critical research into the underlying causes of the disease and in finding new kinds of treatments -- research that may one day lead to a cure.
Myriad Genetics, Press Release. ClinicalTrials.gov. Gordon K. Wilcock, Sandra E. Black, Suzanne B. Hendrix, et al: "Efficacy and Safety of Tarenflurbil in Mild to Moderate Alzheimer's Disease: A Randomised Phase II Trial." Lancet Neurology: Published online, April 30, 2008