This guidance document provides important insights into the context w/in which the AVXL trials are playing out. I am not claiming mine is the only reading to use but it is at least a start for me to make some sense out of what is going on.
We recognize that the AD treatment efficacy," on the path to overt dementia" has check points which trial sponsors have debated.(are the stages even real they say?) The trial debates seem to trip over cognition vs functional diagnostic criteria.
We have seen clinical observation text stating they are not sure there really is stage 1, it goes from there. My limited understanding all along has been w/o knowing how to measure AD then we are doomed to multi year trials in an effort to prove some science. So far this trials practice goes no where but it is all there has been.
The brilliance (I claim) of the AVXL trial plan w/PDD and RS is it should show the MOA (thx XENA) demonstrated in these should show/demonstrate FUNCTIONAL (sleep, spasm, movement range, etc) results which are more easily and accurately measured early on a time line. The end points will demonstrate this plan and (IMO) RWE/RWD will support along w/caregiver reports and anecdotes. So what you say, we already knew that.
So, before the dementia curtain starts to come down on AD patients valuable time is lost, we have to get that back while we try to develop biomarkers that really tell us something. IMO, that is what is going on right now while we wait for the trials to start. Since AD stage cannot yet be measured w/confidence (functional) until it is too late the PDD/RS trials are vicariously on the point while the AD debate of function vs cognition rages for stage 1,2. The early choice of these two CNS disease trials as indicators (along w/other choices we do not know about) are evidence of a good plan.
Stand by, we are going to actually learn something about CNS diseases, then comes applied knowledge.