The principal route of pitavastatin metabolism is glucuronidation via liver uridine 5'-diphosphate glucuronosyltransferase (UGT) with subsequent formation of pitavastatin lactone. There is only minimal metabolism by the cytochrome P450 system. Pitavastatin is marginally metabolized by CYP2C9 and to a lesser extent by CYP2C8. The major metabolite in human plasma is the lactone, which is formed via an ester-type pitavastatin glucuronide conjugate by UGTs (UGT1A3 and UGT2B7).
Pitavastatin has been studied for its effects on hepatic microsomal drug metabolism in rats, and the activities of several drug-metabolizing enzymes have been measured. No induction of the drug metabolizing enzymes (aniline hydroxylase, aminopyrine N-demethylase, 7-ethoxycoumarin O-deethylase and UDP-glucuronic acid transferase) was found in the pitavastatin group compared to the control after the multiple administrations of pitavastatin at the dosage of 1-10 mg/kg per day for 7 days. Based on several different in vitro approaches, it is concluded that CYP2C9 is the enzyme responsible for the metabolism of pitavastatin and no metabolite is present in renal and intestinal microsomes. The CYP2C9 polymorphism was not involved in the pitavastatin metabolism. No inhibitory effect in CYP-mediated metabolism was detected on the tolbutamide 4-hydroxylation (CYP2C9) and testosterone 6 beta-hydroxylation (CYP3A4) in the presence of pitavastatin. The results suggested that pitavastatin did not affect the drug-metabolizing systems.
Pitavastatin is marginally metabolized by CYP2C9 and to a lesser extent by CYP2C8. The major metabolite in human plasma is the lactone which is formed via an ester-type pitavastatin glucuronide conjugate by uridine 5'-diphosphate (UDP) glucuronosyltransferase (UGT1A3 and UGT2B7).
To elucidate any potential species differences, the in vitro metabolism of pitavastatin and its lactone was studied with hepatic and renal microsomes from rats, dogs, rabbits, monkeys and humans. With the addition of UDP-glucuronic acid to hepatic microsomes, pitavastatin lactone was identified as the main metabolite in several animals, including humans. Metabolic clearances of pitavastatin and its lactone in monkey hepatic microsome were much greater than in humans. M4, a metabolite of pitavastatin with a 3-dehydroxy structure, was converted to its lactone form in monkey hepatic microsomes in the presence of UDP-glucuronic acid as well as to pitavastatin. These results implied that lactonization is a common pathway for drugs such as 5-hydroxy pentanoic acid derivatives. The acid forms were metabolized to their lactone forms because of their structural characteristics. UDP-glucuronosyltransferase is the key enzyme responsible for the lactonization of pitavastatin, and overall metabolism is different compared with humans owing to the extensive oxidative metabolism of pitavastatin and its lactone in monkey.
IDENTIFICATION AND USE: Pitavastatin, a hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitor (i.e., statin), is an antilipemic agent. It is used as an adjunct to lifestyle modifications for the management of dyslipidemias. HUMAN EXPOSURE AND TOXICITY: Pitavastatin is contraindicated for use in pregnant women or patients with active liver disease, including unexplained, persistent elevations in serum aminotransferase concentrations. Cases of myopathy and rhabdomyolysis with acute renal failure secondary to myoglobinuria have been reported with HMG-CoA reductase inhibitors, including pitavastatin. These risks can occur at any dose level, but increase in a dose-dependent manner. Cases of fatal and nonfatal hepatic failure have also been reported rarely in patients receiving pitavastatin. ANIMAL STUDIES: In a 92-week carcinogenicity study in mice given pitavastatin, at the maximum tolerated dose of 75 mg/kg/day there was an absence of drug-related tumors. However, in a 92-week carcinogenicity study in rats given pitavastatin at 1, 5, 25 mg/kg/day by oral gavage, there was a significant increase in the incidence of thyroid follicular cell tumors at 25 mg/kg/day. Embryo-fetal developmental studies were conducted in pregnant rats treated with 3, 10, 30 mg/kg/day pitavastatin by oral gavage during organogenesis. No adverse effects were observed at 3 mg/kg/day. Embryo-fetal developmental studies were conducted in pregnant rabbits treated with 0.1, 0.3, 1 mg/kg/day pitavastatin by oral gavage during the period of fetal organogenesis. Maternal toxicity consisting of reduced body weight and abortion was observed at all doses tested. In perinatal/postnatal studies in pregnant rats given oral gavage doses of pitavastatin at 0.1, 0.3, 1, 3, 10, 30 mg/kg/day from organogenesis through weaning, maternal toxicity consisting of mortality at 0.3 mg/kg/day and impaired lactation at all doses contributed to the decreased survival of neonates in all dose groups. Pitavastatin had no adverse effects on male and female rat fertility at oral doses of 10 and 30 mg/kg/day, respectively. Pitavastatin was not mutagenic in the Ames test with Salmonella typhimurium and Escherichia coli with and without metabolic activation, the micronucleus test following a single administration in mice and multiple administrations in rats, the unscheduled DNA synthesis test in rats, and a Comet assay in mice. In the chromosomal aberration test, clastogenicity was observed at the highest doses tested which also elicited high levels of cytotoxicity.
Less information is available on the potential hepatotoxicity of pitavastatin in comparison to other more widely used statins. In large clinical trials, pitavastatin therapy was associated with mild, asymptomatic and usually transient serum aminotransferase elevations in approximately 1% of patients, but levels above 3 times the upper limit of normal (ULN) were infrequent and no cases of clinically apparent hepatitis were reported from the preregistration clinical trials. Since marketing of pitavastatin, however, the sponsor has received reports of jaundice, hepatitis and hepatic failure including fatal cases. However, the clinical features and typical course of the liver injury associated with pitavastatin have not been defined in the published literature. On the other hand, the other statins have all been implicated in cases of clinically apparent acute liver injury that typically arise after 1 to 6 months of therapy with either a cholestatic or hepatocellular pattern of serum enzyme elevations. Rash, fever and eosinophilia are uncommon, but some cases have been marked by autoimmune features including autoantibodies, chronic hepatitis on liver biopsy and a clinical response to corticosteroid therapy. This pattern has yet to be shown to apply to pitavastatin.
Pitavastatin peak plasma concentrations are achieved about 1 hour after oral administration. Both Cmax and AUC0-inf increased in an approximately dose-proportional manner for single pitavastatin doses from 1 mg to 24 mg once daily. The absolute bioavailability of pitavastatin oral solution is 51%. The Cmax and AUC of pitavastatin did not differ following evening or morning drug administration. In healthy volunteers receiving 4 mg pitavastatin, the percent change from baseline for LDL-C following evening dosing was slightly greater than that following morning dosing. Pitavastatin was absorbed in the small intestine but very little in the colon. Compared to other statins, pitavastatin has a relatively high bioavailability, which has been suggested to occur due to enterohepatic reabsorption in the intestine following intestinal absorption. Genetic differences in the OATP1B1 (organic-anion-transporting polypeptide 1B1) hepatic transporter encoded by the SCLCO1B1 gene (Solute Carrier Organic Anion Transporter family member 1B1) have been shown to impact pitavastatin pharmacokinetics. Evidence from pharmacogenetic studies of the c.521T>C single nucleotide polymorphism (SNP) in the gene encoding OATP1B1 (SLCO1B1) demonstrated that pitavastatin AUC was increased 3.08-fold for individuals homozygous for 521CC compared to homozygous 521TT individuals. Other statin drugs impacted by this polymorphism include [simvastatin], [pitavastatin], [atorvastatin], and [rosuvastatin]. Individuals with the 521CC genotype may be at increased risk of dose-related adverse effects including myopathy and rhabdomyolysis due to increased exposure to the drug.
A mean of 15% of radioactivity of orally administered, single 32 mg 14C-labeled pitavastatin dose was excreted in urine, whereas a mean of 79% of the dose was excreted in feces within 7 days.
/MILK/ It is not known whether pitavastatin is excreted in human milk, however, it has been shown that a small amount of another drug in this class passes into human milk. Rat studies have shown that pitavastatin is excreted into breast milk.
DISUBSTITUTED TRIFLUOROMETHYL PYRIMIDINONES AND THEIR USE
申请人：BAYER PHARMA AKTIENGESELLSCHAFT
公开号：US20160221965A1
公开（公告）日：2016-08-04
The present application relates to novel 2,5-disubstituted 6-(trifluoromethyl)pyrimidin-4(3H)-one derivatives, to processes for their preparation, to their use alone or in combinations for the treatment and/or prevention of diseases, and to their use for preparing medicaments for the treatment and/or prevention of diseases, in particular for treatment and/or prevention of cardiovascular, renal, inflammatory and fibrotic diseases.
[EN] PROCESSES FOR MAKING TRIAZOLO[4,5D] PYRAMIDINE DERIVATIVES AND INTERMEDIATES THEREOF<br/>[FR] PROCÉDÉS DE PREPARATION DE DÉRIVÉS DE TRIAZOLO [4,5 D] PYRIMIDINE ET INTERMÉDIAIRES DE CEUX-CI
申请人：CORVUS PHARMACEUTICALS INC
公开号：WO2018183965A1
公开（公告）日：2018-10-04
Provided herein are, inter alia, methods for making triazolo[4,5]pyramidine derivatives and intermediates thereof that are useful for treating diseases.
[EN] TARGETING COMPOUNDS<br/>[FR] COMPOSÉS DE CIBLAGE
申请人：ZAFGEN INC
公开号：WO2019118612A1
公开（公告）日：2019-06-20
The disclosure provides, at least in part, liver, intestine and/or kidney-targeting compounds and their use in treating liver, intestine and/or kidney disorders, such as non-alcoholic steatohepatitis, alcoholic steatohepatitis, hepatocellular carcinoma, liver cirrhosis, and hepatitis B; and/or chronic kidney disease, glomerular disease such as IGA nephropathy, lupus nephritis, or polycystic kidney disease. The compounds are contemplated to have activity against methionyl aminopeptidase 2.
Dibenzyl amine compounds and derivatives, pharmaceutical compositions containing such compounds and the use of such compounds to elevate certain plasma lipid levels, including high density lipoprotein-cholesterol and to lower certain other plasma lipid levels, such as LDL-cholesterol and triglycerides and accordingly to treat diseases which are exacerbated by low levels of HDL cholesterol and/or high levels of LDL-cholesterol and triglycerides, such as atherosclerosis and cardiovascular diseases in some mammals, including humans.
