Atomoxetine undergoes biotransformation primarily through the cytochrome P450 2D6 (CYP2D6) enzymatic pathway. People with reduced activity in the CYP2D6 pathway (also known as poor metabolizers or PMs) have higher plasma concentrations of atomoxetine compared with people with normal activity (also known as extensive metabolizers, or EMs). For PMs, the AUC of atomoxetine at steady-state is approximately 10-fold higher and Cmax is about 5-fold greater than for EMs. The major oxidative metabolite formed regardless of CYP2D6 status is 4-hydroxy-atomoxetine, which is rapidly glucuronidated. 4-Hydroxyatomoxetine is equipotent to atomoxetine as an inhibitor of the norepinephrine transporter, but circulates in plasma at much lower concentrations (1% of atomoxetine concentration in EMs and 0.1% of atomoxetine concentration in PMs). In individuals that lack CYP2D6 activity, 4-hydroxyatomoxetine is still the primary metabolite, but is formed by several other cytochrome P450 enzymes and at a slower rate. Another minor metabolite, N-Desmethyl-atomoxetine is formed by CYP2C19 and other cytochrome P450 enzymes, but has much less pharmacological activity than atomoxetine and lower plasma concentrations (5% of atomoxetine concentration in EMs and 45% of atomoxetine concentration in PMs).
Atomoxetine is metabolized primarily through the CYP2D6 enzymatic pathway. People with reduced activity in this pathway (PMs) have higher plasma concentrations of atomoxetine compared with people with normal activity (EMs). For PMs, AUC of atomoxetine is approximately 10-fold and Css, max is about 5-fold greater than EMs. Laboratory tests are available to identify CYP2D6 PMs.
The major oxidative metabolite formed, regardless of CYP2D6 status, is 4-hydroxyatomoxetine, which is glucuronidated. 4-Hydroxyatomoxetine is equipotent to atomoxetine as an inhibitor of the norepinephrine transporter but circulates in plasma at much lower concentrations (1% of atomoxetine concentration in extensive metabolizers (EMs) and 0.1% of atomoxetine concentration in PMs). 4-Hydroxyatomoxetine is primarily formed by CYP2D6, but in PMs, 4-hydroxyatomoxetine is formed at a slower rate by several other cytochrome P450 enzymes. N-Desmethylatomoxetine is formed by CYP2C19 and other cytochrome P450 enzymes, but has substantially less pharmacological activity compared with atomoxetine and circulates in plasma at lower concentrations (5% of atomoxetine concentration in EMs and 45% of atomoxetine concentration in poor metabolizers (PMs)).
The role of the polymorphic cytochrome p450 2D6 (CYP2D6) in the pharmacokinetics of atomoxetine hydrochloride [(-)-N-methyl-gamma-(2-methylphenoxy)benzenepropanamine hydrochloride; LY139603] has been documented following both single and multiple doses of the drug. In this study, the influence of the CYP2D6 polymorphism on the overall disposition and metabolism of a 20-mg dose of (14)C-atomoxetine was evaluated in CYP2D6 extensive metabolizer (EM; n = 4) and poor metabolizer (PM; n = 3) subjects under steady-state conditions. Atomoxetine was well absorbed from the gastrointestinal tract and cleared primarily by metabolism with the preponderance of radioactivity being excreted into the urine. In EM subjects, the majority of the radioactive dose was excreted within 24 hr, whereas in PM subjects the majority of the dose was excreted by 72 hr. The biotransformation of atomoxetine was similar in all subjects undergoing aromatic ring hydroxylation, benzylic oxidation, and N-demethylation with no CYP2D6 phenotype-specific metabolites. The primary oxidative metabolite of atomoxetine was 4-hydroxyatomoxetine, which was subsequently conjugated forming 4-hydroxyatomoxetine-O-glucuronide. Due to the absence of CYP2D6 activity, the systemic exposure to radioactivity was prolonged in PM subjects (t(1/2) = 62 hr) compared with EM subjects (t(1/2) = 18 hr). In EM subjects, atomoxetine (t(1/2) = 5 hr) and 4-hydroxyatomoxetine-O-glucuronide (t(1/2) = 7 hr) were the principal circulating species, whereas atomoxetine (t(1/2) = 20 hr) and N-desmethylatomoxetine (t(1/2) = 33 hr) were the principal circulating species in PM subjects. Although differences were observed in the excretion and relative amounts of metabolites formed, the primary difference observed between EM and PM subjects was the rate at which atomoxetine was biotransformed to 4-hydroxyatomoxetine.
Atomoxetine is excreted primarily as 4-hydroxyatomoxetine-O-glucuronide, mainly in the urine (greater than 80% of the dose) and to a lesser extent in the feces (less than 17% of the dose). Only a small fraction of the Strattera dose is excreted as unchanged atomoxetine (less than 3% of the dose), indicating extensive biotransformation.
IDENTIFICATION AND USE: Atomoxetine, as Strattera, is indicated for the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD). HUMAN EXPOSURE AND TOXICITY: Atomoxetine increased the risk of suicidal ideation in short-term studies in children or adolescents with ADHD. Symptoms accompanying acute and chronic overdoses of atomoxetine include gastrointestinal symptoms, somnolence, dizziness, tremor, abnormal behavior, hyperactivity, agitation, and signs and symptoms consistent with mild to moderate sympathetic nervous system activation (e.g., tachycardia, blood pressure increased, mydriasis, dry mouth). Less commonly, there have been reports of QT prolongation and mental changes, including disorientation and hallucinations. Atomoxetine may cause clinically significant hepatotoxicity either by metabolic idiosyncrasy or by inducing autoimmune hepatitis. There have been fatalities reported involving a mixed ingestion overdose of Strattera and at least one other drug. Sudden deaths, stroke, and myocardial infarction have been reported in both children and adults with structural cardiac abnormalities or other serious heart problems. ANIMAL STUDIES: The median lethal oral dose of atomoxetine hydrochloride in animals was estimated to be 25 mg/kg for cats, >37.5 mg/kg for dogs, and 0.190 mg/kg in rats and mice. Premonitory signs of toxicity following single oral doses of atomoxetine in animals included mydriasis and reduced pupillary light reflex, mucoid stools, salivation, vomiting, ataxia, tremors, myoclonic jerking, and convulsions. Chronic toxicity studies of up to 1 year were conducted in adult rats and dogs. There was no major target organ toxicity observed in dogs given oral doses up to 16 mg/kg/day or in rats given atomoxetine in the diet at time-weighted average doses up to 47 mg/kg/day. These doses are 4-5 times the maximum recommended daily oral dose in adults. Mild hepatic effects, characterized by mottling and pallor of the liver, increased relative liver weights, hepatocellular vacuolation, and slightly increased serum ALT values, occurred in male rats given time weighted average doses >/= 14 mg/kg/day. No hepatic effects were observed in dogs. Clinical signs of mydriasis, reduced pupillary light reflex, emesis, and tremors were observed in dogs, and these effects were minimal in adult dogs given >/= 8 mg/kg/day. No evidence of drug-associated teratogenicity or retarded fetal development was produced in rabbits or rats administered atomoxetine hydrochloride throughout organogenesis at oral doses up to 100 mg/kg/day and 150 mg/kg/day (13 times the maximum recommended daily oral dose in adults). In a rat fertility study, decreased pup weight and survival was observed, predominantly during the first week postpartum following maternal dietary atomoxetine timeweighted average doses of 23 mg/kg/day or higher. Atomoxetine hydrochloride was negative in a battery of genotoxicity studies that included a reverse point mutation assay (Ames Test), an in vitro mouse lymphoma assay, a chromosomal aberration test in Chinese hamster ovary cells, an unscheduled DNA synthesis test in rat hepatocytes, and an in vivo micronucleus test in mice. However, there was a slight increase in the percentage of Chinese hamster ovary cells with diplochromosomes, suggesting endoreduplication (numerical aberration). Atomoxetine hydrochloride was not carcinogenic in rats and mice when given in the diet for 2 years at time-weighted average doses up to 47 and 458 mg/kg/day, respectively.
The precise mechanism by which atomoxetine produces its therapeutic effects in Attention-Deficit/Hyperactivity Disorder (ADHD) is unknown, but is thought to be related to selective inhibition of the pre-synaptic norepinephrine transporter, as determined through in-vitro studies. Atomoxetine appears to have minimal affinity for other noradrenergic receptors or for other neurotransmitter transporters or receptors.
Atomoxetine has been linked to serum aminotransferase elevations in a small proportion of patients (~0.5%). More importantly, there have been several reports of clinically apparent acute liver injury due to atomoxetine. The onset of injury was within 3 to 12 weeks of starting the medication. The typical pattern of serum enzyme elevations was hepatocellular with marked increases in serum aminotransferase levels (often >20 times upper limit of normal) and clinical features that resembled acute viral hepatitis. Most cases have been self-limited, but instances of acute liver failure sometimes requiring emergency liver transplantation have been reported. Immunoallergic features were not found, but several patients with acute injury had antinuclear antibody and at least one patient had other features that resembled autoimmune hepatitis (with typical liver histology and high levels of immunoglobulins in serum).
The pharmacokinetic profile of atomoxetine is highly dependent on cytochrome P450 2D6 genetic polymorphisms of the individual. A large fraction of the population (up to 10% of Caucasians and 2% of people of African descent and 1% of Asians) are poor metabolizers (PMs) of CYP2D6 metabolized drugs. These individuals have reduced activity in this pathway resulting in 10-fold higher AUCs, 5-fold higher peak plasma concentrations, and slower elimination (plasma half-life of 21.6 hours) of atomoxetine compared with people with normal CYP2D6 activity. Atomoxetine is rapidly absorbed after oral administration, with absolute bioavailability of about 63% in extensive metabolizers (EMs) and 94% in poor metabolizers (PMs). Mean maximal plasma concentrations (Cmax) are reached approximately 1 to 2 hours after dosing with a maximal concentration of 350 ng/ml with an AUC of 2 mcg.h/ml.
Atomoxetine is excreted primarily as 4-hydroxyatomoxetine-O-glucuronide, mainly in the urine (greater than 80% of the dose) and to a lesser extent in the feces (less than 17% of the dose). Only a small fraction (less than 3%) of the atomoxetine dose is excreted as unchanged atomoxetine, indicating extensive biotransformation.
The reported volume of distribution of oral atomoxetine was 1.6-2.6 L/kg. The steady-state volume of distribution of intravenous atomoxetine was approximately 0.85 L/kg.
Steady-state volume of distribution (intravenous administration): 8.5 L/kg. Atomexetine distributes primarily into total body water; volume of distribution is similar across patient weight range after normalizing for body weight.
[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.
NAPHTHALENE-BASED INHIBITORS OF ANTI-APOPTOTIC PROTEINS
申请人：Pellecchia Maurizio
公开号：US20090105319A1
公开（公告）日：2009-04-23
Methods of using apogossypol and its derivatives for treating inflammation is disclosed. Also, there is described a group of compounds having structure A, or a pharmaceutically acceptable salt, hydrate, N-oxide, or solvate thereof are provided:
wherein each R is independently selected from the group consisting of H, C(O)X, C(O)NHX, NH(CO)X, SO
2
NHX, and NHSO
2
X, wherein X is selected from the group consisting of an alkyl, a substituted alkyl, an aryl, a substituted aryl, an alkylaryl, and a heterocycle. Compounds of group A may be used for treating various diseases or disorders, such as cancer.
[EN] QUINAZOLINE DERIVATIVES, COMPOSITIONS, AND USES RELATED THERETO<br/>[FR] DÉRIVÉS DE QUINAZOLINE, COMPOSITIONS ET UTILISATIONS ASSOCIÉES
申请人：UNIV EMORY
公开号：WO2013181135A1
公开（公告）日：2013-12-05
The disclosure relates to quinazoline derivatives, compositions, and methods related thereto. In certain embodiments, the disclosure relates to inhibitors of NADPH-oxidases (Nox enzymes) and/or myeloperoxidase.
Disclosed herein are substituted indole cysteinyl leukotriene receptor modulators of Formula I, process of preparation thereof, pharmaceutical compositions thereof, and methods of use thereof.
Direct C-S bond coupling is an attractive way to construct aryl sulfur ether, a building block for a variety of biological active molecules. Herein, we disclose an effective model for regioselective thiolation of the aromatic C-Hbond by thiolactivation instead of arene activation. Strikingly, this method has been applied into anisole derivatives that are not available in the arene activation approach
