Tom Murphy
RedwoodAge.com

A midstage trial showed that an antihistamine used in Russia since 1983 can halt or slow the onset of Alzheimers disease, which already affects as many as 5.1 million Americans and is expected to hit millions more as baby boomers age.

The drug, Dimebon, is one of more than four dozen Alzheimer's drugs now in development. Together, researchers expect this new flood of drugs to change the way Alzheimer's is viewed by patients and the medical community. Dimebon, for example, can't cure the disease. But, so far, it has helped to stabilize the symptoms in most victims with relatively minor side effects.

Other drugs, such as Alzhemed, might actually help reverse the symptoms by clearing away the plak between nerve cells that interferes with the brain's ability to transmit impulses. A report on Alzhemed's trial is expected this month.

Medivation, the San Francisco-based company that is trying to bring Dimebon to the US market, will officially report results of its midstage trial in Washington on Tuesday at the Alzheimer's Association International Conference on Prevention of Dementia. But the company's stock jumped 21 percent Monday after the company put out a news release outlining the results.

Dimebon had already proven itself effective in an early stage trial last year. Now, a six-month, second-stage trial turned in results that were as good as or better than the initial results. A third and final trial is planned for next year, although it would likely take several years for the drug to hit the US market even if those results are strong.

"Given these data and the fact that Dimebon was well-tolerated in this study, I consider Dimebon one of the most promising Alzheimer's disease compounds in development," said Dr. Jeffrey Cummings, a UCLA professor of neurology, who was not involved in the study.

Even so, any celebration should remain a long way off. The Dimebon study was based on just 138 patients with mild to moderate Alzheimers. Of those, half were given a placebo. During the trial, 18 patients dropped out, so just 120 patients finished the trial, which was conducted in Russia.

"The natural history of untreated Alzheimer's disease include decline in thinking abilities, social behavior and function," said Dr. Rachel Doody, who led the study. "By contrast, after a full year of therapy, Dimebon-treated patients did not decline in any of these areas."

Fast-growing Problem
The progress is very welcome. One in eight Americans over 65 suffer from Alzheimer's today. Half of those over 85 have Alzheimer's. With 78 million baby boomers fast approaching those ages - the oldest boomers are 61 now - that number is expected to skyrocket unless science can stop the disease.

Johns Hopkins University reported Sunday that 26 million people have the disease worldwide, and the number is expected to quadruple by 2050. The study said 3.1 million Americans have the disease now, but the number would jump to 8.8 million by 2050.

"If we can make even modest advances in preventing Alzheimer's disease, or delay its progression, we could have a huge global public health impact," said Ron Brookmeyer, a public health specialist at the school. The university's study was funded by Elan and Wyeth, two pharmaceutical companies that are working on treatments.

A separate US study recently estimated that 5.1 million Americans have the disease now, and 16 million will have it by 2050. By then, the youngest baby boomers - those born in 1964 - will be 86.