I've notice a few posts about donepezil and memantine on the forum and uncertainty in there use. Not sure if this article will help, but it offers more information about the use of these drugs from the DOMINO-AD protocol. The project was closed in 2009. It is worth a read if your curious about wanting to know clinical outcomes
https://trialsjournal.biomedcentral.com/articles/10.1186/1745-6215-10-57
https://trialsjournal.biomedcentral.com/articles/10.1186/1745-6215-10-57