Why clinical trials fail -- another reason. This article talks about a guy who was misdiagnosed with Alzheimer's at age 39, and was in multiple clinical trials. So, of course, he didn't respond to the drugs. This is one of the reasons why some clinical trials show great results for sub-groups of patients and no results for others -- because they didn't actually have the disease.

https://www.washingtonpost.com/national/healt...0ccee11a65