Details of Drug Interaction | MecDDI

Drug General Information (ID: DDISCOKHLJ)
Drug Name			Colchicine		Drug Info		Fosnetupitant		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antigout Agents				Antiemetics
Structure

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

Drug Name		Colchicine				Fosnetupitant
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 Colchicine caused by Fosnetupitant mediated inhibition of CYP450 enzyme

Recommended Action
Management		Caution is advised if colchicine is prescribed in combination with moderate CYP450 3A4 inhibitors. In patients with normal renal and hepatic function, the dosage of colchicine should be reduced when used with moderate CYP450 3A4 inhibitors or within 14 days of using them. For the treatment of acute gout flares, the adjusted dosage recommended is 1.2 mg for one dose. Administration should not be repeated for at least three days. For the prophylaxis of gout flares, the adjusted dosage should be 0.3 mg twice a day (or 0.6 mg once a day) if the original regimen was 0.6 mg twice a day, and 0.3 mg once a day if the original regimen was 0.6 once a day. For the treatment of familial Mediterranean fever, the maximum dosage of colchicine is 1.2 mg/day (may be given as 0.6 mg twice a day) when used in the presence of moderate CYP450 3A4 inhibitors. Other significant inhibitors of CYP450 3A4 include amiodarone, dronedarone, imatinib, posaconazole, and quinupristin-dalfopristin, although the extent to which they may interact with colchicine is unknown. A similar dosage adjustment may be required. Patients should be advised to contact their physician if they experience symptoms of toxicity such as abdominal pain, nausea, vomiting, diarrhea, fatigue, myalgia, asthenia, hyporeflexia, paresthesia, and numbness.

References
1	Dogukan A, Oymak FS, Taskapan H, Guven M, Tokgoz B, Utas C "Acute fatal colchicine intoxication in a patient on continuous ambulatory peritoneal dialysis (CAPD). Possible role of clarithromycin administration." Clin Nephrol 55 (2001): 181-2. [PMID: 11269688]
2	Severe colchicine-macrolide interactions. Prescrire Int 12 (2003): 18-9. [PMID: 12602385]
3	Tateishi T, Soucek P, Caraco Y, Guengerich FP, Wood AJ "Colchicine biotransformation by human liver microsomes. Identification of CYP3A4 as the major isoform responsible for colchicine demethylation." Biochem Pharmacol 53 (1996): 111-6. [PMID: 8960070]