Not being able to offer a treatment is always frustrating. I'm glad I mostly do MS with so many great options -- at least for the majority with relapsing forms.
My interpretation is that Adu has a real but mediocre effect in early AD and that this slight benefit would need to be balanced against adverse events, cost of healthcare/patient/caregiver time and societal monetary costs. I expect the FDA will not approve it at this time but will leave a path open for a tiebreak study at the higher dose, maybe just in ApoE4 positive patients.