Novel oxysterols activate the Hedgehog pathway and induce osteogenesis

Structure-activity relationship studies of oxysterol 4 have identified analogues such as 18, 21 and 30. These analogues are characterized by higher potency in a osteoblast differentiation assay and/or by increased metabolic stability in human liver microsomes. Oxysterols 4, 18 and 21 were evaluated in vivo in a rat spinal fusion model.