Monday, July 19, 2010


Last week I posted on a new proposal for the diagnosis of Alzheimer's disease, one that will allow doctors to make that diagnosis earlier so that treatment can begin earlier. Later in the week, the New York Times reported what I consider to be equally important news with respect to that earlier treatment.

The article, while lengthy, is an excellent one. It details the history of the discovery of the disease and the ongoing research into its source and progressive nature. For that alone, the article deserves a close reading. However, it also provides an important view on the caution which the Food and Drug Administration is exercising with respect to current and future clinical trials being run by pharmaceutical companies with new drugs that are designed to combat the disease by slowing and eliminating the development of the amyloid plaque in the brain.

The reason for that caution is a good one: about 90% of researchers believe that the plaque tangles are not just a symptom of the disease but are rather the source for the destruction of brain cells leading to the loss of memory and the later horrific ravages of the disease which lead to death. That's the current scientific model for the disease, but it's not one which is universally accepted. What happens if it's wrong? What happens if the drugs currently being developed do in fact remove the amyloid plaque, but the disease is not affected? What happens if the drug's side effects are, in the long run, just as bad as the disease itself?

Dr. Russell Katz, director of the F.D.A.’s division of neurology products, is in a quandary about Alzheimer’s drugs. What, he must decide, should be the criteria for showing that a drug works?

Should the F.D.A. say it is sufficient to show that a treatment prevents or lessens the formation of plaque?

The agency is not ready to do that, Dr. Katz said.

“You only care if down the road the patient gets better,” Dr. Katz said. “What we are concerned about is approving a drug based on a lab test and being wrong about what happens to the patient clinically.”

With Alzheimer’s, Dr. Katz said, “the great fear is that maybe amyloid has nothing to do with the disease.” If that were the case, and the agency approved a drug that blocked amyloid formation, millions of healthy people could end up taking something useless or even dangerous. And because it takes so long for Alzheimer’s to develop, it could be decades, if ever, before anyone knew the drug did not work.

While nothing would make me happier than to have a new drug available in the next five years to fight Alzheimer's, a disease that has ravaged my family, I think Dr. Katz's caution is laudable. It doesn't mean that the drug makers should back off; what it does mean is that they will have to use the same caution and to exercise a little patience. And that's why the change in the diagnosis protocols for Alzheimer's was such a big deal. Researchers will be able to start the clinical trials earlier, giving the drugs a chance to prove their efficacy in removing the amyloid and in changing the course of the disease.

Patience is not my long suit, but I'm beginning to learn its importance.



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