Myriad Genetics Doesn't Make the Grade

Researchers I've consulted say that Myriad's approach to lowering beta-amyloid plaques -- in this case, by working upstream where enzymes cut APP into the sticky fragments -- is feasible.

But the hurdles inherent in this approach are high. It's difficult to get enough drug into the brain to have a therapeutic effect on gamma secretase (as opposed to just getting sufficient drug levels in plasma).

Myriad has presented retrospective analyses from the phase II study showing patients that were able to achieve higher blood levels of Flurizan performed better. But the problem is that it's difficult -- maybe impossible -- to know in advance which patients will be able to achieve those higher concentrations of Flurizan in their system.

The U.S.-based phase III trial of Flurizan has enrolled 1,600 patients with mild Alzheimer's (randomized to drug or placebo) and uses the same clinical endpoints from the phase II study. These clinical measures, however, will be assessed after 18 months of treatment.

Expect to see that data in the first half of 2008. We'll wait a while for the final data to determine the ultimate outcome, but I'm skeptical that Flurizan will be able to achieve a statistically significant benefit for patients of Alzheimer's.

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