ACHE and dementia: Liu et al. (2019) counted 2,117 clinical trials testing various approaches for the treatment of AD. As a result, no new drug for AD has been approved since the approval of memantine (an NMDAR antagonist) in 2003 following the approval in 2001 of galantamine, the last of four acetylcholine esterase inhibitors (AChEIs) (the others being tacrine, donepezil, rivastigmine) recommended in the treatment of dementia (Cummings et al., 2014).