Drug General Information (ID: DDIBTLIM0C)
  Drug Name Mitotane Drug Info Everolimus Drug Info
  Drug Type Small molecule Small molecule
  Therapeutic Class Antineoplastics Antineoplastics
  Structure

 Mechanism of Mitotane-Everolimus Interaction (Severity Level: Major)
     CYP450 enzyme induction Click to Show/Hide Mechanism Graph
Could Not Find 2D Structure
      Drug Name Mitotane Everolimus
      Mechanism CYP450 3A4 inducer CYP450 3A4 substrate
      Key Mechanism Factor 1
Factor Name Cytochrome P450 3A4
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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
  • Increased metabolism of Everolimus caused by Mitotane mediated induction of CYP450 enzyme

Recommended Action
      Management Concomitant use of everolimus with potent CYP450 3A4 and/or P-gp inducers should generally be avoided. alternative therapeutic agents with less enzyme induction potential should be considered. Some manufacturers recommend that, if concomitant use is unavoidable, the daily everolimus dose should be doubled to achieve the recommended therapeutic range for the condition being treated. Please refer to the manufacturer's labeling for specific dosing information. If the potent CYP450 3A4 and/or P-gp inducer is discontinued, the everolimus dosage should be returned to the dosage used before the potent inducer was commenced after a washout period of approximately 3 to 5 days. Everolimus whole blood trough levels should be closely monitored during treatment, particularly 2 weeks after a dose increase, and 2 weeks after discontinuation of the potent inducers.

References
1 Canadian Pharmacists Association.
2 Cerner Multum, Inc. "Australian Product Information.".
3 Cerner Multum, Inc. "UK Summary of Product Characteristics.".
4 Product Information. Afinitor (everolimus). Novartis Pharmaceuticals, East Hanover, NJ.
5 Product Information. Zortress (everolimus). Novartis Pharmaceuticals, East Hanover, NJ.