Ro 48-8071 fumarate is an orally active 2,3-oxidosqualene lanosterol cyclase (OSC) inhibitor where OSC represents a unique target for a cholesterol-lowering drug. Partial inhibition of OSC should reduce synthesis of lanosterol and subsequent sterols, and also stimulate the production of epoxysterols that repress HMG-CoA reductase expression, generating a synergistic, self-limited negative regulatory loop.