There are more than 100 Alzheimer’s studies looking for a whopping 25,000 participants, Mr. Dwyer said. To begin filling them all, 37.5 million patients in the right age group would first have to be informed. And with an 80 percent screening failure rate, that leaves 25,000 participants of the 37.5 million who were first informed. The numbers make it clear: There’s no way scientists are going to find 25,000 participants for all of the Alzheimer’s trials that have been approved. Pfizer, after a series of failures, announced in January that it was getting out of the Alzheimer’s race altogether.

Source: New York Times July 23, 2018 16:22 UTC