While we're on the topic: the FDA draft guidance is specifically for early AD, and specifically addresses just two trial factors: diagnostic criteria and endpoints. Notably, it does not guide on trial size or dropouts.
What to make of this? A couple things are clear:
1. The guidelines arguably reduce the uncertainty or evaluator discretion on what is to be considered "early AD" and what is to be considered necessary endpoints.
2. The guidelines don't reduce the uncertainty or discretion on what is to be considered adequate trial size or excessive dropouts. Ie, they don't specify them.
This 'can be' good for us, if it means that #1 is their primary concern (ie, not trial size or dropouts rates). Whether that's true or not, can't say for sure. Furthermore as Doc has pointed out, are we 100% sure our population was truly overall "early AD"?