Absolutely, the belief in scientific circles is that the way forward to develop cures (or at least treatment that slows down the progression) is to treat it early. When you get to the point where you start showing clear symptoms, your brain is already mush. If you have a potential treatment that attacks the root cause, you would have to catch the very early, pre-clinical, stages of the disease, but without good diagnostics there is no way to do that (short of giving the disease to a wide swath of the population, like a vaccine... but that gets expensive very quickly, and side effects become a bigger worry.