Accumulation of amyloid-β (Aβ) peptide is a pathological hallmark of Alzheimers disease (AD).Reduction of Aβ is believed to be a promising approach for the treatment ofAD.Aβ is generated by the proteolytic cleavage of amyloid precursor protein (APP) by β-and β-secretases.Two classes of therapeutic agents are under development for the reduction of Aβ through β-secretases:β-secretases inhibitors (GSI) and B-secretases modulators (GSM).