Atri A, et al. - This trial was designed in order to gauge the efficacy of idalopirdine, a selective 5-hydroxytryptamine-6 receptor antagonist for the symptomatic treatment of mild to moderate Alzheimer's disease (AD). No improvement was yielded in the cognition over 24 weeks of idalopirdine treatment compared with placebo in the patients. Hence its use was not recommended for the treatment of AD.