No idea why you are being downvoted. Yes, removing the plaque has been tried and has so far been unsuccessful at improving Alzheimer's. The way I picture it (

No idea why you are being downvoted. Yes, removing the plaque has been tried and has so far been unsuccessful at improving Alzheimer's. The way I picture it (and I'm not an expert, still learning about this stuff myself) is to look at amyloid plaque as a clog in a pipe between nerve cells. Now picture the blockage putting a crack in the pipe. You can clear the blockage, but you still have a cracked pipe, so anything you send down the pipe will spill out. We have no way of fixing the broken pipe, so we must prevent the build up of the plaque in the first place.