Details of Drug Interaction | MecDDI

Drug General Information (ID: DDI2RP4BGU)
Drug Name			Lovastatin		Drug Info		Itraconazole		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Statins/Antihyperlipidemic Agents				Antifungal Agents
Structure

Mechanism of Lovastatin-Itraconazole Interaction (Severity Level: Major)
CYP450 enzyme inhibition Click to Show/Hide Mechanism Graph

Drug Name		Lovastatin				Itraconazole
Mechanism		CYP450 3A4 substrate				CYP450 3A4 inhibitor
Key Mechanism Factor 1
		Factor Name		Cytochrome P450 3A4				× Structure Sequence MALIPDLAMETWLLLAVSLVLLYLYGTHSHGLFKKLGIPGPTPLPFLGNILSYHKGFCMFDMECHKKYGKVWGFYDGQQPVLAITDPDMIKTVLVKECYSVFTNRRPFGPVGFMKSAISIAEDEEWKRLRSLLSPTFTSGKLKEMVPIIAQYGDVLVRNLRREAETGKPVTLKDVFGAYSMDVITSTSFGVNIDSLNNPQDPFVENTKKLLRFDFLDPFFLSITVFPFLIPILEVLNICVFPREVTNFLRKSVKRMKESRLEDTQKHRVDFLQLMIDSQNSKETESHKALSDLELVAQSIIFIFAGYETTSSVLSFIMYELATHPDVQQKLQEEIDAVLPNKAPPTYDTVLQMEYLDMVVNETLRLFPIAMRLERVCKKDVEINGMFIPKGVVVMIPSYALHRDPKYWTEPEKFLPERFSKKNKDNIDPYIYTPFGSGPRNCIGMRFALMNMKLALIRVLQNFSFKPCKETQIPLKLSLGGLLQPEKPVVLKVESRDGTVSGA
		Gene Name		CYP3A4
		Uniprot ID		CP3A4_HUMAN
		KEGG Pathway		hsa:1576
		Protein Family		Cytochrome P450 family
		Protein Function		A cytochrome P450 monooxygenase involved in the metabolism of sterols, steroid hormones, retinoids and fatty acids (PubMed:10681376, PubMed:11093772, PubMed:11555828, PubMed:14559847, PubMed:12865317, PubMed:15373842, PubMed:15764715, PubMed:20702771, PubMed:19965576, PubMed:21490593, PubMed:21576599). Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (NADPH--hemoprotein reductase). Catalyzes the hydroxylation of carbon-hydrogen bonds (PubMed:2732228, PubMed:14559847, PubMed:12865317, PubMed:15373842, PubMed:15764715, PubMed:21576599, PubMed:21490593). Exhibits high catalytic activity for the formation of hydroxyestrogens from estrone (E1) and 17beta-estradiol (E2), namely 2-hydroxy E1 and E2, as well as D-ring hydroxylated E1 and E2 at the C-16 position (PubMed:11555828, PubMed:14559847, PubMed:12865317). Plays a role in the metabolism of androgens, particularly in oxidative deactivation of testosterone (PubMed:2732228, PubMed:15373842, PubMed:15764715, PubMed:22773874). Metabolizes testosterone to less biologically active 2beta- and 6beta-hydroxytestosterones (PubMed:2732228, PubMed:15373842, PubMed:15764715). Contributes to the formation of hydroxycholesterols (oxysterols), particularly A-ring hydroxylated cholesterol at the C-4beta position, and side chain hydroxylated cholesterol at the C-25 position, likely contributing to cholesterol degradation and bile acid biosynthesis (PubMed:21576599). Catalyzes bisallylic hydroxylation of polyunsaturated fatty acids (PUFA) (PubMed:9435160). Catalyzes the epoxidation of double bonds of PUFA with a preference for the last double bond (PubMed:19965576). Metabolizes endocannabinoid arachidonoylethanolamide (anandamide) to 8,9-, 11,12-, and 14,15-epoxyeicosatrienoic acid ethanolamides (EpETrE-EAs), potentially modulating endocannabinoid system signaling (PubMed:20702771). Plays a role in the metabolism of retinoids. Displays high catalytic activity for oxidation of all-trans-retinol to all-trans-retinal, a rate-limiting step for the biosynthesis of all-trans-retinoic acid (atRA) (PubMed:10681376). Further metabolizes atRA toward 4-hydroxyretinoate and may play a role in hepatic atRA clearance (PubMed:11093772). Responsible for oxidative metabolism of xenobiotics. Acts as a 2-exo-monooxygenase for plant lipid 1,8-cineole (eucalyptol) (PubMed:11159812). Metabolizes the majority of the administered drugs. Catalyzes sulfoxidation of the anthelmintics albendazole and fenbendazole (PubMed:10759686). Hydroxylates antimalarial drug quinine (PubMed:8968357). Acts as a 1,4-cineole 2-exo-monooxygenase (PubMed:11695850). Also involved in vitamin D catabolism and calcium homeostasis. Catalyzes the inactivation of the active hormone calcitriol (1-alpha,25-dihydroxyvitamin D(3)) (PubMed:29461981). Click to Show/Hide
Mechanism Description		Decreased metabolism of Lovastatin caused by Itraconazole mediated inhibition of CYP450 enzyme

Recommended Action
Management		The concurrent use of itraconazole with lovastatin and simvastatin is considered contraindicated by the manufacturer. Some authorities consider concomitant administration of lovastatin or simvastatin and itraconazole to be contraindicated during and for 2 weeks after treatment with itraconazole. When concomitant use of an azole antifungal and an HMG-CoA reductase inhibitor is required, pravastatin which is not metabolized by CYP450 enzymes, or fluvastatin which is metabolized by CYP450 2C9, are recommended.

References
1	Canadian Pharmacists Association.
2	Cerner Multum, Inc. "Australian Product Information.".
3	Cerner Multum, Inc. "UK Summary of Product Characteristics.".
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5	Horn M "Coadministration of itraconazole with hypolipidemic agents may induce rhabdomyolysis in healthy individuals." Arch Dermatol 132 (1996): 1254. [PMID: 8859048]
6	Kivisto KT, Kantola T, Neuvonen PJ "Different effects of itraconazole on the pharmacokinetics of fluvastatin and lovastatin." Br J Clin Pharmacol 46 (1998): 49-53. [PMID: 9690949]
7	Lees RS, Lees AM "Rhabdomyolysis from the coadministration of lovastatin and the antifungal agent itraconazole." N Engl J Med 333 (1995): 664-5. [PMID: 7637734]
8	Lomaestro BM, Piatek MA "Update on drug interactions with azole antifungal agents." Ann Pharmacother 32 (1998): 915-28. [PMID: 9762380]
9	Neuvonen PJ, Jalava KM "Itraconazole drastically increases plasma concentrations of lovastatin and lovastatin acid." Clin Pharmacol Ther 60 (1996): 54-61. [PMID: 8689812]
10	Neuvonen PJ, Kantola T, Kivisto KT "Simvastatin but not pravastatin is very susceptible to interaction with the CYP3A4 inhibitor itraconazole." Clin Pharmacol Ther 63 (1998): 332-41. [PMID: 9542477]
11	Product Information. Sporanox (itraconazole). Janssen Pharmaceutica, Titusville, NJ.