Discovery and development of statins as they directly compete with the endogenous substrate for the active site cavity of HMGR. Statins are also noncompetitive with the cosubstrate NADPH (nicotinamide adenine dinucleotide phosphate). By blocking the HMGR enzyme they inhibit the synthesis of cholesterol via the mevalonate pathway. The end result is lower LDL (Low Density Lipoprotein), TG (Triglycerides) and total cholesterol levels as well as increased HDL (High Density Lipoprotein) levels in serum). The ideal statin should have the following properties: One of the main design objectives of statin design is the selective inhibition of HMGR in the liver, as cholesterol synthesis in non-hepatic cells
Discovery and development of statins lipophilic and also had the largest percentage of serious adverse effects due to its ability to inhibit vascular smooth muscle proliferation and as a result was voluntarily removed from the market by the manufacturer. All statins are (metabolized) by the liver, which causes their low systemic bioavailability. Lovastatin and simvastatin are administered in their lactone forms, which is more lipophilic than their free acid forms, and therefore they have to be activated by hydrolysis to the active anionic carboxylate form. Cytochrome P450(CYP) isoenzymes are involved in the oxidative metabolism of the statins, with CYP3A4 and CYP2C9 isoenzymes being the most