Discovery and development of statins polar methane sulfonamide group, which is quite hydrophilic and confers low lipophilicity. The sulfonamide group forms a unique polar interaction with the enzyme. As a result, rosuvastatin has superior binding affinity to the HMGR enzyme compared to the other statins, which is directly related to its efficiency to lower LDL cholesterol. Lipophilicity of the statins is considered to be quite important since the hepatoselectivity of the statins is related to their lipophilicity. The more lipophilic statins tend to achieve higher levels of exposure in non-hepatic tissues, while the hydrophilic statins tend to be more hepatoselective. The difference in selectivity is
Specialty drugs in the United States and prescribe." Drugs are most typically defined as specialty because they are expensive. They are high cost "both in total and on a per-patient basis". High-cost medications are typically priced at more than $1,000 per 30-day supply. The Medicare Part D program "defines a specialty drug as one that costs more than $600 per month". Most of the prescriptions filled by Pennsylvania-licensed Philidor Rx Services, a specialty online mail-order pharmacy, which mainly sold Valeant Pharmaceuticals International Inc expensive drugs directly to patients and handled insurance claims on the customers' behalf, such as Solodyn, Jublia, and Tretinoin, would be considered specialty