The treatment options for Alzheimer's disease are in some ways limited. The three drugs that we have in one class called cholinesterase inhibitors have been around for a good while and basically, their mechanism is that we know in people with Alzheimer's disease, they start to lose a neurotransmitter called acetylcholine. There’s an enzyme that breaks down acetylcholine that’s called cholinesterase. What we do is we give a drug, a cholinesterase inhibitor to make that enzyme less able to break down the acetylcholine that’s in the brain. Early in Alzheimer's disease when there’s still enough brain cells around to make that chemical, then, it makes sense that that would work. Later in the disease though, there are not many brain cells left that are making the acetylcholine, so we don’t know whether actually giving it or not toward the end or later stages of Alzheimer's disease makes much difference.
The other class of drugs that we have is … The generic name is memantine. Most people would know it by Namenda. Basically, it protects damaged brain cells from further injury from glutamate which is a normal chemical that’s in the brain. For some reason, glutamate will attack these injured brain cells in Alzheimer's disease and make them die faster. The Namenda or memantine will protect the brain cell a little bit longer. Neither of them are cures.
Most of the studies with those drugs would indicate that they may slow down the progression from being able to be at home to go into a nursing home. That’s what most of them do. If you look at some of the studies that look at small changes in memory or function, yeah, you may be able to measure that but when you actually talk to the family members, they would say, “Well, I don’t notice much difference.”
Now, clearly, when you're treating a disease that has no known cure, there’s a tremendous, almost placebo-like effect that can go along with it because we’re doing something. We’re thinking about it. We’re trying this medicine. We’re going to add this medicine when the time comes but at the same time, we’re trying to do other interventions as well. We’re trying to look at the environment, look at behavioral responses that caregivers have and so forth. It’s very hard. It’s very hard to decide.
