In another example of how discoveries in medicine (and any science) sometimes take a strange turn, researchers have found that an older antihistamine that worked by blocking certain signals in the brain can also protect brain tissue. In fact, the drug called dimebon significantly improved the symptom of memory loss for patients in a landmark study published in the medical journal, Lancet.

The dimebon study took a group of patients with mild to moderate Alzheimer’s and placed them randomly in two groups: one group received 20 mg of dimebon three times a day and the other group received a placebo.

The difference between patients in the two groups was significant, according to researchers. Symptoms were assessed using a cognitive scale based on knowledge of dates, memorization of words, the ability to understand instructions and follow commands, as well as performance of simple tasks. The difference in scores between the patients on the placebo and the patients on dimebon was 7 points on the research scale, showing a clear advantage to patients on dimebon.

When reviewing the results, researchers not only found short-term benefits but when patients continued on dimebon, benefits actually increased over a 12-month period. No other drug has been able to generate this kind of increasing benefit in Alzheimer’s patients. While dimebon patients improved, the control group in the study continued to worsen, as is typical in the progression of Alzheimer’s.

Such exciting research for patients with an otherwise gloomy prognosis has the medical field abuzz. Currently, treatment options for Alzheimer’s patients are limited and the benefit of most treatment is small.

Dimebon was the main antihistamine used in Russia before more advanced antihistamines hit the market, but had lost favor with the advent of other allergy treatments. It appears it will have a new lease on life with the discovery of its benefits to Alzheimer’s patients. More research is already planned for drug.

Do not look for dimebon to hit the market quickly in North America, despite promising trials. Even though this drug is now in international, multi-centred clinical trials, it could be as much as 10 years before this is an available treatment.
(Lancet)