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
Specialty drugs in the United States are often defined as specialty because their price is much higher than that of non-specialty drugs. Medicare defines any drug for which the negotiated price is $670 per month or more, as a specialty drug which is placed in a specialty tier that requires a higher patient cost sharing. Drugs are also identified as specialty when there is a special handling requirement or the drug is only available via a limited distributions network. By 2015 "specialty medications accounted for one-third of all spending on drugs in the United States, up from 19 percent in 2004 and heading toward 50 percent