Tetrabenazine is hepatically metabolized. Carbonyl reductase in the liver is responsible for the formation of two major active metabolites: α-dihydrotetrabenazine (α-HTBZ) and β-dihydrotetrabenazine (β-HTBZ). α-HTBZ is further metabolized into 9-desmethyl-α-DHTBZ, a minor metabolite by CYP2D6 and with some contribution of CYP1A2. β-HTBZ is metabolized to another major circulating metabolite, 9-desmethyl-β-DHTBZ, by CYP2D6. The Tmax of this metabolite is 2 hours post-administration of tetrabenazine.
In a mass balance study in 6 healthy volunteers, approximately 75% of the dose was excreted in the urine, and fecal recovery accounted for approximately 7 to 16% of the dose. Unchanged tetrabenazine has not been found in human urine. Urinary excretion of alpha-dihydrotetrabenazine (a-HTBZ) or beta-dihydrotetrabenazine (b-HTBZ) accounted for less than 10% of the administered dose. Circulating metabolites, including sulfate and glucuronide conjugates of HTBZ metabolites as well as products of oxidative metabolism, account for the majority of metabolites in the urine.
来源:Hazardous Substances Data Bank (HSDB)
代谢
口服给药后,四苯喹嗪在肝脏广泛代谢,代谢物主要通过肾脏排出。
After oral administration, tetrabenazine is extensively hepatically metabolized, and the metabolites are primarily renally eliminated.
The results of in vitro studies do not suggest that tetrabenazine, alpha-dihydrotetrabenazine (a-HTBZ), beta-dihydrotetrabenazine (b-HTBZ) or 9-desmethyl-beta-dihydrotetrabenazine are likely to result in clinically significant inhibition of CYP2D6, CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2E1, or CYP3A. In vitro studies suggest that neither tetrabenazine nor its a- or b-HTBZ or 9-desmethyl-beta-dihydrotetrabenazine metabolites are likely to result in clinically significant induction of CYP1A2, CYP3A4, CYP2B6, CYP2C8, CYP2C9, or CYP2C19.
After oral administration in humans, at least 19 metabolites of tetrabenazine have been identified. alpha-Dihydrotetrabenazine (a-HTBZ), beta-dihydrotetrabenazine (b-HTBZ) and 9-desmethyl-beta-dihydrotetrabenazine are the major circulating metabolites and are subsequently metabolized to sulfate or glucuronide conjugates. a-HTBZ and b-HTBZ are formed by carbonyl reductase that occurs mainly in the liver. a-HTBZ is O-dealkylated by CYP450 enzymes, principally CYP2D6, with some contribution of CYP1A2 to form 9-desmethyl-alpha-dihydrotetrabenazine, a minor metabolite. b-HTBZ is O-dealkylated principally by CYP2D6 to form 9-desmethyl-beta-dihydrotetrabenazine.
IDENTIFICATION AND USE: Tetrabenazine is a solid. It is used as adrenergic uptake inhibitor for the treatment of chorea associated with Huntington's disease. Pharmacology studies demonstrate that betrabenzaine reversibly inhibits the activity of vesicular monoamine transporter 2, resulting in depletion of central dopamine. HUMAN STUDIES: Adverse effects are dose and age related and include depression, fatigue, parkinsonism, and somnolence. Neuroleptic malignant syndrome (NMS), a potentially fatal syndrome, has been reported in patients receiving tetrabenazine and other drugs that reduce dopaminergic transmission. Three episodes of overdose occurred in the open-label trials performed in support of registration. Eight cases of overdose have been reported in the literature. The dose of the drug in these patients ranged from 100 mg to 1 g. Adverse reactions associated with overdose include acute dystonia, oculogyric crisis, nausea and vomiting, sweating, sedation, hypotension, confusion, diarrhea, hallucinations, rubor, and tremor. Completed suicide, attempted suicide, and 6 cases of suicidal ideation were reported in 187 tetrabenazine recipients. Major human metabolite 9-Desmethyl-beta-dihydrotetrabenazine was not clastogenic in an in vitro chromosomal aberration assay in human peripheral blood mononuclear cells in the presence or absence of metabolic activation. ANIMAL STUDIES: No increase in tumors was observed in transgenic mice treated orally with a major human metabolite, 9-desmethyl-beta-dihydrotetrabenazine (20, 100, and 200 mg/kg/day), for 26 weeks. Oral administration of tetrabenazine (5, 15, or 30 mg/kg/day) to female rats prior to and throughout mating, and continuing through day 7 of gestation resulted in disrupted estrous cyclicity at doses greater than 5 mg/kg/day. No effects on mating and fertility indices or sperm parameters (motility, count, density) were observed when male rats were treated orally with tetrabenazine (5, 15, or 30 mg/kg/day. However, because rats dosed with tetrabenazine do not produce 9-desmethyl-beta-dihydrotetrabenazine, a major human metabolite, this study may not have adequately assessed the potential of the drug to impair fertility in humans. Oral administration of 9-desmethyl-beta-dihydrotetrabenazine (8, 15, and 40 mg/kg/day) to pregnant and lactating rats throughout the period of organogenesis produced increases in embryofetal mortality at 15 and 40 mg/kg/day and reductions in fetal body weights at 40 mg/kg/day, which was also maternally toxic. When 9-desmethyl-beta-dihydrotetrabenazine (8, 15, and 40 mg/kg/day) was orally administered to pregnant rats from the beginning of organogenesis through the lactation period, increases in gestation duration, stillbirths, and offspring postnatal mortality (40 mg/kg/day); decreases in pup weights (40 mg/kg/day); and neurobehavioral (increased activity, learning and memory deficits) and reproductive (decreased litter size) impairment (15 and 40 mg/kg/day) were observed. Maternal toxicity was seen at the highest dose. Tetrabenazine and metabolites alpha-dihydrotetrabenazine (a-HTBZ), beta-dihydrotetrabenazine (b-HTBZ), and 9-desmethyl-beta-dihydrotetrabenazine were negative in an in vitro bacterial reverse mutation assay. Tetrabenazine was clastogenic in an in vitro chromosomal aberration assay in Chinese hamster ovary cells in the presence of metabolic activation. a-HTBZ and b-HTBZ were clastogenic in an in vitro chromosome aberration assay in Chinese hamster lung cells in the presence and absence of metabolic activation. In vivo micronucleus assays were conducted in male and female rats and male mice. Tetrabenazine was negative in male mice and rats but produced an equivocal response in female rats.
Tetrabenazine has not been associated with rates of serum enzyme elevations greater than occur with placebo therapy, but information on liver test results during therapy is limited and occasional instances of asymptomatic ALT elevations leading to drug discontinuation or dose modification have been reported by the sponsor. In prelicensure pivotal registration trials in several hundred patients, tetrabenazine was not associated with cases of jaundice or hepatitis. Since licensure, there have been no published reports of clinically apparent liver injury, jaundice or hepatitis attributed to tetrabenazine. Thus, clinically apparent liver injury with jaundice due to tetrabenazine must be rare, if it occurs at all.
Following oral administration of tetrabenazine, the extent of absorption is at least 75%. After single oral doses ranging from 12.5 to 50 mg, plasma concentrations of tetrabenazine are generally below the limit of detection because of the rapid and extensive hepatic metabolism of tetrabenazine. Food does not affect the absorption of tetrabenazine. Cmax, oral = 4.8 ng/mL in HD or tardive dyskinesia patients; Tmax, oral = 69 min in HD or tardive dyskinesia patients
After oral administration, tetrabenazine is extensively hepatically metabolized, and the metabolites are primarily renally eliminated (75%). Tetrabenazine is also cleared fecally (7% to 16%). Unchanged tetrabenazine has not been found in human urine. Urinary excretion of α-HTBZ or β-HTBZ (the major metabolites) accounted for less than 10% of the administered dose.
Steady State, IV, in HD or tardive dyskinesia patients: 385L. Tetrabenazine is rapidly distributed to the brain following IV injection. The site with the highest binding is the striatum, while the lowest binding was observed in the cortex.
来源:DrugBank
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清除
IV, 1.67 L/min 在血液透析或迟发性运动障碍患者中
IV, 1.67 L/min in HD or tardive dyskinesia patients
The in vitro protein binding of tetrabenazine, alpha-dihydrotetrabenazine (a-HTBZ), and beta-dihydrotetrabenazine (b-HTBZ) was examined in human plasma for concentrations ranging from 50 to 200 ng/mL. Tetrabenazine binding ranged from 82% to 85%, a-HTBZ binding ranged from 60% to 68%, and b-HTBZ binding ranged from 59% to 63%.
[EN] COMPOUNDS FOR THE TREATMENT OF AMYLOID-ASSOCIATED DISEASES<br/>[FR] COMPOSÉS POUR LE TRAITEMENT DE MALADIES ASSOCIÉES À LA SUBSTANCE AMYLOÏDE
申请人:REMYND NV
公开号:WO2016083490A1
公开(公告)日:2016-06-02
This invention provides novel compounds of formulae (I) or (II) or a stereoisomer, enantiomer, racemic, or tautomer thereof, (I) (II) wherein the substituents are as defined in the specification. The present invention also relates to the novel compounds for use as a medicine, more in particular for the prevention or treatment of amyloid-related diseases, more specifically certain neurological disorders, such as disorders collectively known as tauopathies, disorders characterized by cytotoxic α-synuclein amyloidogenesis. The present invention also relates to the use of said novel compounds for the manufacture of medicaments useful for treating such amyloid-related diseases. The present invention further relates to pharmaceutical compositions including said novel compounds and to methods for the preparation of said novel compounds.
[EN] SUBSTITUTED N-HETEROCYCLIC CARBOXAMIDES AS ACID CERAMIDASE INHIBITORS AND THEIR USE AS MEDICAMENTS<br/>[FR] CARBOXAMIDES N-HÉTÉROCYCLIQUES SUBSTITUÉS UTILISÉS EN TANT QU'INHIBITEURS DE LA CÉRAMIDASE ACIDE ET LEUR UTILISATION EN TANT QUE MÉDICAMENTS
申请人:BIAL BIOTECH INVEST INC
公开号:WO2021055627A1
公开(公告)日:2021-03-25
The invention provides substituted N-heterocyclic carboxamides and related compounds, compositions containing such compounds, medical kits, and methods for using such compounds and compositions to treat a medical disorder, e.g., cancer, lysosomal storage disorder, neurodegenerative disorder, inflammatory disorder, in a patient.
[EN] METHYL OXAZOLE OREXIN RECEPTOR ANTAGONISTS<br/>[FR] MÉTHYLOXAZOLES ANTAGONISTES DU RÉCEPTEUR DE L'OREXINE
申请人:MERCK SHARP & DOHME
公开号:WO2016089721A1
公开(公告)日:2016-06-09
The present invention is directed to methyl oxazole compounds which are antagonists of orexin receptors. The present invention is also directed to uses of the compounds described herein in the potential treatment or prevention of neurological and psychiatric disorders and diseases in which orexin receptors are involved. The present invention is also directed to compositions comprising these compounds. The present invention is also directed to uses of these compositions in the potential prevention or treatment of such diseases in which orexin receptors are involved.
Heterobicyclic compounds of Formula (I):
or a pharmaceutically-acceptable salt, tautomer, or stereoisomer thereof, as defined in the specification, and compositions containing them, and processes for preparing such compounds. Provided herein also are methods of treating disorders or diseases treatable by inhibition of PDE10, such as obesity, non-insulin dependent diabetes, schizophrenia, bipolar disorder, obsessive-compulsive disorder, Huntington's Disease, and the like.
Formula (I)的杂环化合物:
或其药用可接受的盐、互变异构体或立体异构体,如规范中所定义,并含有它们的组合物,以及制备这种化合物的方法。本文还提供了通过抑制PDE10来治疗由此可治疗的疾病或疾病的方法,如肥胖症、非胰岛素依赖型糖尿病、精神分裂症、躁郁症、强迫症、亨廷顿病等。
[EN] NAPHTHALENE CARBOXAMIDE M1 RECEPTOR POSITIVE ALLOSTERIC MODULATORS<br/>[FR] COMPOSÉS DE NAPHTHALÈNE CARBOXAMIDE, MODULATEURS ALLOSTÉRIQUES POSITIFS DU RÉCEPTEUR M1
申请人:MERCK SHARP & DOHME
公开号:WO2011149801A1
公开(公告)日:2011-12-01
The present invention is directed to naphthalene carboxamide compounds of formula (I) which are M1 receptor positive allosteric modulators and that are useful in the treatment of diseases in which the M1 receptor is involved, such as Alzheimers disease, schizophrenia, pain or sleep disorders. The invention is also directed to pharmaceutical compositions comprising the compounds and to the use of the compounds and compositions in the treatment of diseases mediated by the M1 receptor.