"A small study shows that a new drug being tested for the treatment of Alzheimers disease https reduces the buildup of plaques in the brain https associated with the fatal disease. The experimental compound known as gantenerumab is being developed by Roche the Swiss pharmaceutical company. The results and especially the rapidity of the effects observed in the gantenerumab trial went beyond our expectations Luca Santarelli MD study coauthor and Roche senior vice president of neuroscience writes in an email. The study is published in the online edition of Archives of Neurology. Santarelli describes gantenerumab as a drug engineered to bind itself to plaques known as amyloidbetas which accumulate as Alzheimers https progresses. In the study patients who received monthly gantenerumab injections showed reductions in such brain https plaques. Continue Reading Below you might like What is not entirely known at this point though is if these plaques cause Alzheimers https or are byproducts of the disease. Therefore its not known if reducing the amount of them will slow or stop the disease. Reducing Plaque Buildup Sixteen patients with Alzheimers disease https participated in the study. Four of them received a placebo https six received milligram injections of gantenerumab and the remaining six received milligram injections. The patients received the treatments once a month for two to seven months. At the end of the study the researchers report the group that was given milligram doses of gantenerumab had a  reduction in plaques compared to the placebo group. Those patients who had been given milligram doses showed a . reduction. But the reductions did not come without complications. Two patients in the latter group developed possible findings of vasogenic edema https or fluid collecting in the brain https tissue as well as microhemorrhages. Since its not completely clear what reductions in brain https plaques mean for Alzheimers patients the researchers are unable to say whether treatment with gantenerumab will bring improvement to patients with Alzheimers. They are currently involved in a new study that they hope will answer that question. This study will address whether the reduction in amyloid reported in our paper is paralleled by a slowing down of cognitive decline of the disease Santarelli writes. We will be studying the effects of gantenerumab on participants ability to remember information to solve problems and to go about daytoday activities. That study will focus on patients with early Alzheimers as well as those with symptoms of the disease that are not severe enough to warrant a full diagnosis. Its important to get to patients early before the disease progresses too far because there is no evidence that gantenerumab or any similar compound would be able to reverse the damage caused by Alzheimers and restore mental abilities that have already been lost. Instead it may at best slow or halt the disease. Effects on Mental Skills Unclear Theres nothing to suggest that it will have any effect on cognition or neurological abilities only on progression says David Teplow PhD. If the authors are correct and it does clear plaques will it help patients We dont know. Teplow a professor of neurology and interim director of Mary S. Easton Center for Alzheimers Disease Research at University of California Los Angeles was not involved with Santarellis study nor he says was he impressed with it. The number of patients was incredibly small Teplow says adding that the patients were also too dissimilar to make meaningful comparisons. There were other problems as well. Whats not new and what is discouraging is that they the researchers see microhemorrhages and edema. Thats a problem in these types of studies and a primary concern with respect to these kinds of treatments says Teplow. We need more studies to know if it safe or effective."