Washing out means that a clinical trial is halted for lack of efficacy. It means the drug candidate in question is safe to ingest, but also doesn't work to tr

Washing out means that a clinical trial is halted for lack of efficacy. It means the drug candidate in question is safe to ingest, but also doesn't work to treat the condition it was designed to treat. "work" is defined as having met or exceeded predefined clinical endpoints; e.g., "cognitive assessment improves by x% on average in a cohort of Y thousand patients", or "blood cholesterol levels reduced by Z%" or whatever. It's important and sad to note, too, that the clinical targets of most modern alzheimers drug candidates are comparatively low bars. We're not shooting for a cure, we're shooting for things like "reliably slows down cognitive decline by 6 months", and we can't even do that.