Valacyclovir is converted to acyclovir and L-valine via first-pass intestinal and/or hepatic metabolism. Acyclovir is also transformed, to a small extent, to inactive metabolites by _aldehyde oxidase_ in addition to _alcohol dehydrogenase_ and _aldehyde dehydrogenase_. Neither valacyclovir nor acyclovir is metabolized by cytochrome P450 enzymes.
来源:DrugBank
代谢
阿昔洛韦的主要代谢物是9-羧甲氧基甲基鸟嘌呤。
... Aciclovir's main metabolite /is/ 9-carboxymethoxymethylguanine. ...
Valacyclovir is converted to acyclovir and L-valine by first-pass intestinal and/or hepatic metabolism. Acyclovir is converted to a small extent to inactive metabolites by aldehyde oxidase and by alcohol and aldehyde dehydrogenase. Neither valacyclovir nor acyclovir is metabolized by cytochrome P450 enzymes. Plasma concentrations of unconverted valacyclovir are low and transient, generally becoming non-quantifiable by 3 hours after administration. Peak plasma valacyclovir concentrations are generally less than 0.5 ug/mL at all doses. After single-dose administration of 1 gram of Valtrex, average plasma valacyclovir concentrations observed were 0.5, 0.4, and 0.8 ug/mL in patients with hepatic dysfunction, renal insufficiency, and in healthy volunteers who received concomitant cimetidine and probenecid, respectively.
**LD50 Oral** Rat – 903.5 mg/kg **Carcinogenesis, Mutagenesis, Impairment of Fertility** Valacyclovir was noncarcinogenic in lifetime carcinogenicity assays at single daily gavage doses of valacyclovir giving plasma acyclovir concentrations equivalent to human levels in the mouse bioassay and 1.4 to 2.3 times human levels in the rat bioassay. No clinically significant difference in the incidence of tumors between treated and control animals was observed, and valacyclovir was not found to shorten the latency period of tumors. Valacyclovir was tested in 5 genetic toxicity assays. An Ames assay was negative in the absence or presence of metabolic activation. An in vitro cytogenetic study with human lymphocytes and a rat cytogenetic study was negative. In the mouse lymphoma assay, valacyclovir was not found to be mutagenic without metabolic activation, however, in the presence of metabolic activation (76% to 88% conversion to acyclovir), valacyclovir was mutagenic. Valacyclovir was also found to be mutagenic in a mouse micronucleus assay. Valacyclovir did not impair fertility or reproduction in rats at 6 times the normal concentrations in human plasma. **Use in pregnancy** Valacyclovir is categorized as a pregnancy category B drug. There are insufficient well-controlled studies of valacyclovir in pregnant women. The general rate of birth defects in infants exposed to acyclovir in-utero is comparable to the rate for infants measured in the general population. This drug should be used during pregnancy only if the potential benefit justifies the possible fetal risk. **Use in nursing** Acyclovir, a major metabolite of valacyclovir, was excreted in breastmilk at lower concentrations when a normal therapeutic dose of valacyclovir was administered. Exercise caution when acyclovir is used while nursing. **A note on renal function and toxicity in elderly patients** Elderly patients and patients with decreased renal function are at increased risk of valacyclovir toxicity, which can sometimes lead to central nervous system effects, such as encephalopathy, agitation, dysarthria, mania, and psychosis, among other effects. Consider reducing the dose of this drug in these populations to decrease the risk of toxicity.
Oral therapy with valacyclovir is associated with a low rate of mild-to-moderate serum aminotransferase elevations, but these abnormalities are usually asymptomatic and self-limited even with continuation of therapy. Complicating the attribution of liver test abnormalities to valacyclovir therapy is the fact that enzyme elevations are not uncommon during the course of varicella-zoster infection (both chickenpox and shingles) and can progress to clinically apparent hepatitis and even acute liver failure. Clinically apparent liver disease due to valacyclovir itself is rare, but isolated reports have been published. The time to onset was short (1 to 2 weeks) and the course mild, with few symptoms and rapid resolution (Case 1). The pattern of liver injury described was mixed hepatocellular-cholestatic. Immunoallergic features and autoantibodies were absent.
After oral administration, valacyclovir hydrochloride is rapidly absorbed from the gastrointestinal (GI) tract and converted to acyclovir and L-valine. The absolute bioavailability of acyclovir after administration of valacyclovir was measured at 54.5% ± 9.1% after the administration of a 1 gram oral dose of valacyclovir and a 350 mg intravenous (IV) acyclovir dose to 12 healthy subjects. Acyclovir (a metabolite of valacyclovir) bioavailability from the administration of this drug is not affected by the administration with food.
After oral administration of a single 1 gram dose of radiolabeled valacyclovir to 4 healthy subjects, 46% and 47% of administered radioactivity was measured in urine and feces, respectively, over 96 hours. Acyclovir accounted for 89% of the radioactivity excreted in the urine.
Cerebrospinal fluid (CSF) penetration, determined by CSF/plasma AUC ratio, is approximately 25% for aciclovir and the metabolite _8-hydroxy-aciclovir_ (8-OH-ACV), and approximately 2.5% for the metabolite _9-(carboxymethoxy)methylguanine_. In a study of immunocompromised pediatric patients, the volume of distribution of a 15 ml/kg dose of valacyclovir was 1.34 ± 0.65 L/kg.
Renal clearance of acyclovir following the administration of a single 1 gram dose of valacylcovir to 12 healthy 437 volunteers was approximately 255 ± 86 mL/min, which represents 42% of total acyclovir apparent plasma clearance.
After oral administration, valacyclovir hydrochloride is rapidly absorbed from the gastrointestinal tract and nearly completely converted to acyclovir and L-valine by first-pass intestinal and/or hepatic metabolism. The absolute bioavailability of acyclovir after administration of Valtrex is 54.5% + or - 9.1% as determined following a 1-gram oral dose of Valtrex and a 350 mg intravenous acyclovir dose to 12 healthy volunteers. Acyclovir bioavailability from the administration of Valtrex is not altered by administration with food (30 minutes after an 873 Kcal breakfast, which included 51 grams of fat).
Tricyclic compounds, protected intermediates thereof, and methods for inhibition of HIV-integrase are disclosed.
三环化合物，其受保护的中间体，以及用于抑制HIV整合酶的方法被披露。
[EN] AZADECALIN DERIVATIVES AS INHIBITORS OF HUMAN IMMUNODEFICIENCY VIRUS REPLICATION<br/>[FR] DÉRIVÉS D'AZADÉCALINE EN TANT QU'INHIBITEURS DE LA RÉPLICATION DU VIRUS DE L'IMMUNODÉFICIENCE HUMAINE
申请人：VIIV HEALTHCARE UK (NO 5) LTD
公开号：WO2018002848A1
公开（公告）日：2018-01-04
Compounds having drug and bio-affecting properties, their pharmaceutical compositions and methods of use are set forth. In particular, azadecaline derivatives that possess unique antiviral activity are provided as HIV maturation inhibitors, as represented by compounds of Formula (I). These compounds are useful for the treatment of HIV and AIDS.
The invention provides compounds of Formula (I)
as described herein, along with pharmaceutically acceptable salts, pharmaceutical compositions containing such compounds, and methods to use these compounds, salts and compositions for treating viral infections, particularly infections caused by hepatitis B virus, and reducing the occurrence of serious conditions associated with HBV.
[EN] POLYCYCLIC PYRIDONE COMPOUNDS AS ANTIVIRALS<br/>[FR] COMPOSÉS PYRIDONES POLYCYCLIQUES UTILES EN TANT QU'AGENTS ANTIVIRAUX
申请人：NOVARTIS AG
公开号：WO2018047109A1
公开（公告）日：2018-03-15
The invention provides compounds of Formula (I) as described herein, along with pharmaceutically acceptable salts, pharmaceutical compositions containing such compounds, and methods to use these compounds, salts and compositions for treating viral infections, particularly infections caused by hepatitis B virus, and reducing the occurrence of serious conditions associated with HBV.
The present invention discloses compounds of Formula (I), and pharmaceutically acceptable salts thereof:
which inhibit the protein(s) encoded by hepatitis B virus (HBV) or interfere with the function of the HBV life cycle of the hepatitis B virus and are also useful as antiviral agents. The present invention further relates to pharmaceutical compositions comprising the aforementioned compounds for administration to a subject suffering from HBV infection. The invention also relates to methods of treating an HBV infection in a subject by administering a pharmaceutical composition comprising the compounds of the present invention.
