Atorvastatin lactone (ATVL) is hydroxylated to hydroxy-metabolites, predominantly by cytochrome P450 3A4 (CYP3A4) (Park et al. 2008). Statin lactones are metabolized to a much higher extent than their acid forms by CYP enzymes, suggesting that metabolism of the lactone is the relevant pathway for atorvastatin elimination (Jacobsen et al. 2000, Fujino et al. 2004, Filppula et al. 2021). Described here is the formation of 4-hydroxyatorvastatin lactone (4-OH-ATVL).
monooxygenase activity of CYP3A4 [endoplasmic reticulum membrane]