(Rac)-3′-Hydroxy simvastatin is the primary active metabolite of simvastatin, a widely prescribed statin drug used to lower cholesterol levels in patients with hyperlipidemia. As the active form, it inhibits HMG-CoA reductase, an enzyme critical for cholesterol biosynthesis, thereby reducing the risk of cardiovascular diseases. It is utilized in pharmaceutical research to study the metabolic pathways, efficacy, and pharmacokinetics of statin drugs. Additionally, it plays a role in developing improved formulations, derivatives, and novel cholesterol-lowering medications.