In addition, preclinicaldata have demonstrated cognition-enhancing properties of 5-HT6R antagonists in rodent models of AD,4,5 schizophrenia,6 and neuropathic pain.7 Additionally, a proof-of-concept clinical trial has confirmed theefficacy of intepirdine (a 5-HT6R antagonist) in alleviatingcognitive deficits in AD. This evidence concerns the gene HTR6 and Alzheimer disease.