isoform involved in metabolism of lovastatin, simvastatin, atorvastatin and cerivastatin. CYP2C9 isoenzyme is the most predominant isoform involved in metabolism of Fluvastatin, but CYP3A4 and CYP2C8 isoenzymes also contribute to the metabolism of Fluvastatin. Rosuvastatin is metabolized to a small degree by CYP2C9 and to a lesser extent by CYP2C19 isoenzymes. Pravastatin is not metabolized by CYP isoenzymes to any appreciable extent. The statins that have the ability to be metabolized by multiple CYP isoenzymes may therefore avoid drug accumulation when one of the pathways is inhibited by co-administered drugs. Comparative pharmacology of statins Future research With the recent elucidation of the structures of the catalytic portion of human HMGR enzyme complexed with six different statins by a series of crystallography studies, new possibilities have opened up for the rational design and optimization of even better HGMR inhibitors. A new study using comparative molecular field analysis (CoMFA) to establish three-dimensional quantitative structure-activity relationship (3D QSAR), while searching for novel active pharmacophores as potentially potent HGMR inhibitors, was recently published. Using this novel technique researchers were able to screen for compounds with high screening scores. In addition to the conventional statin-like compounds with HMG-like moiety, eight additional compounds with completely different pharmacophore structure were found. This structure-based virtual screening procedure is considered promising for rational quest and optimization of potential novel HGMR inhibitors. References Drug discovery