GAB, it is interesting that almost 2/3 of the patients are claimed to be still taking 2-73 after at least 148weeks (extended into 208 weeks!!). Point is this is a large percentage of Alzheimer patients, who generally decline!
Also, the patients are still participating in tests, evaluations, maybe visits to AU neurology hospitals. Point is, it is not easy, but rather a BURDEN for them or their caregiver, to continue to participate. (For a drug that it is not working?)
I think these 2 points are good indirect evidence of efficacy.
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