Scientists Find Way to Sneak Alzheimer's Drug Into Brain

Scientists have found a way to help Alzheimer's drugs seep inside the brain faster—by temporarily breaching its protective shield. The novel experiment was a first attempt in just three patients. But in spots in the brain where the new technology took aim, researchers say it enhanced removal of Alzheimer's trademark brain-clogging plaque, reports the AP. "Our goal is to give patients a head start," by boosting some new Alzheimer's treatments that take a long time to work, said Dr. Ali Rezai of West Virginia University's Rockefeller Neuroscience Institute, who led the study.

At issue is what's called the blood-brain barrier, a protective lining in blood vessels that prevents germs and other damaging substances from leaching into brain from the bloodstream. But it also can block drugs for Alzheimer's, tumors, and other neurologic diseases, requiring higher doses for longer periods for enough to reach their target inside the brain. Now scientists are using a technology called focused ultrasound to jiggle temporary openings in that shield. First, they inject microscopic bubbles into the bloodstream. Then they beam sound waves through a helmetlike device to a precise brain area. The pulses of energy vibrate the microbubbles, which loosen gaps in the barrier enough for medications to slip in.

Prior small studies have found the technology can safely poke tiny holes that seal up in 48 hours. Now Rezai's team has gone a step further—administering an Alzheimer's drug at the same time. PET scans showed patients' plaque levels before and after the six months of medication. There was about 32% greater reduction in spots where the blood-brain barrier was breached compared to the same region on the brain's opposite side, the researchers report in the New England Journal of Medicine. The pilot study is elegant but too tiny to draw any conclusions, cautioned Dr. Eliezer Masliah of the National Institute on Aging. Still, "it's very exciting," added Masliah, who wasn't involved with the research. "It opens the door for more extensive, larger studies definitely." (More Alzheimer's disease stories.)