Darunavir is heavily oxidized and metabolized by hepatic cytochrome enzymes, mainly CYP3A. Darunavir is extensively metabolized in subjects who do not receive a booster, primarily via carbamate hydrolysis, isobutyl aliphatic hydroxylation, and aniline aromatic hydroxylation, as well as both benzylic aromatic hydroxylation and glucuronidation.
In vitro experiments with human liver microsomes (HLMs) indicate that darunavir primarily undergoes oxidative metabolism. Darunavir is extensively metabolized by CYP enzymes, primarily by CYP3A. A mass balance study in healthy volunteers showed that after a single dose administration of 400 mg (14)C-darunavir, co-administered with 100 mg ritonavir, the majority of the radioactivity in the plasma was due to darunavir. At least 3 oxidative metabolites of darunavir have been identified in humans; all showed activity that was at least 90% less than the activity of darunavir against wild-type HIV.
Absorption, metabolism, and excretion of darunavir, an inhibitor of human immunodeficiency virus protease, was studied in eight healthy male subjects after a single oral dose of 400 mg of ((14)C)darunavir given alone (unboosted subjects) or with ritonavir (100 mg b.i.d. 2 days before and 7 days after darunavir administration (boosted subjects)). ... Darunavir was extensively metabolized in unboosted subjects, mainly by carbamate hydrolysis, isobutyl aliphatic hydroxylation, and aniline aromatic hydroxylation and to a lesser extent by benzylic aromatic hydroxylation and glucuronidation. Total excretion of unchanged darunavir accounted for 8.0% of the dose in unboosted subjects. Boosting with ritonavir resulted in significant inhibition of carbamate hydrolysis, isobutyl aliphatic hydroxylation, and aniline aromatic hydroxylation but had no effect on aromatic hydroxylation at the benzylic moiety, whereas excretion of glucuronide metabolites was markedly increased but still represented a minor pathway. Total excretion of unchanged darunavir accounted for 48.8% of the administered dose in boosted subjects as a result of the inhibition of darunavir metabolism by ritonavir. Unchanged darunavir in urine accounted for 1.2% of the administered dose in unboosted subjects and 7.7% in boosted subjects, indicating a low renal clearance.
Darunavir is metabolized by Phase I and Phase II biotransformation mechanisms. A large number of metabolites were detected in vitro using animal and human hepatocytes and microsomal preparations. The metabolic pathway was qualitatively similar in rats, dogs and humans. The most prevalent pathway was the Phase I biotransformation including carbamate hydrolysis, aliphatic hydroxylation at the isobutyl moiety and aromatic hydroxylation at the aniline moiety. Dogs were most representatives of human with carbamate hydrolysis predominating in both species. Darunavir was mainly metabolized by CYP3A. In mice and rats darunavir treatment induced hepatic microsomal CYP3A4. UDP-GT activity was additionally induced in rats. In dogs, no induction effects were observed. Darunavir is presented as a single enantiomer but no chiral inversion occurs in vivo.
Some degree of serum aminotransferase elevations occur in a high proportion of patients taking darunavir containing antiretroviral regimens. Moderate-to-severe elevations in serum aminotransferase levels (above 5 times the upper limit of normal) are found in 3% to 10% of patients overall, and rates are higher in patients with HIV-HCV coinfection. In clinical trials of darunavir elevations in serum ALT above 5 times ULN occurred in 2% to 3% of patients, but no subject developed clinically apparent liver injury with jaundice. The serum enzyme elevations during therapy are usually asymptomatic and self-limited and can resolve even with continuation of the medication. Clinically apparent acute liver injury due to darunavir has been reported since its approval and more widescale use, but none have been well characterized for clinical features. The liver injury generally arises after 1 to 8 weeks of therapy and the pattern of serum enzyme elevations is usually, but not always, hepatocellular. Signs of hypersensitivity (fever, rash, eosinophilia) are rare, as is autoantibody formation. The acute liver injury is usually self-limited and resolves within a few weeks of stopping darunavir. However, fatal instances have been reported, at least to the sponsor and monitoring of liver enzymes during therapy is recommended.
Finally, initiation of darunavir based highly active antiretroviral therapy can lead to exacerbation of an underlying chronic hepatitis B or C in coinfected individuals, typically arising 2 to 12 months after starting therapy and associated with a hepatocellular pattern of serum enzyme elevations and increases in serum levels of hepatitis B virus (HBV) DNA or hepatitis C virus (HCV) RNA. Darunavir therapy has not been clearly linked to lactic acidosis and acute fatty liver that is reported in association with several nucleoside analogue reverse transcriptase inhibitors.
Likelihood score: D (possible, rare cause of clinically apparent liver injury).
The absolute oral bioavailability of one single 600 mg dose of darunavir alone and with 100 mg of ritonavir twice a day was 37% and 82%, respectively. Exposure to darunavir in boosted patients has been found to be 11 times higher than in unboosted patients. Tmax is achieved approximately 2.4 to 4 hours after oral administration. When darunavir is taken with food, the Cmax and AUC of darunavir given with ritonavir increase by 30% when compared to the fasted state.
A mass balance study in healthy volunteers demonstrated that after single dose administration of 400 mg 14C-darunavir, given with 100 mg ritonavir, approximately 79.5% and 13.9% of the administered dose of radiolabeled darunavir was obtained in the feces and urine, respectively. Excretion of unchanged drug accounted for 8.0% of the darunavir dose in volunteers who were unboosted. In boosted darunavir administration, unchanged darunavir made up 48.8% of the excreted dose in boosted subjects due to inhibition of darunavir metabolism by ritonavir. Unchanged drug in the urine made up 1.2% of the administered dose in volunteers who where unboosted, and 7.7% in boosted volunteers.
The volume of distribution of darunavir in one pharmacokinetic study in conjunction with ritonavir was 206.5 L (with a range of 161.0–264.9) in healthy young adult volunteers. Another pharmacokinetic study revealed a volume of distribution of 220 L.
Darunavir has a low renal clearance. After intravenous administration, the clearance darunavir administered alone and with 100 mg ritonavir twice daily, was 32.8 L/h and 5.9 L/h, respectively.
PROCESS FOR SYNTHESIS OF SYN AZIDO EPOXIDE AND ITS USE AS INTERMEDIATE FOR THE SYNTHESIS OF AMPRENAVIR & SAQUINAVIR
申请人：Council of Scientific & Industrial Research
公开号：US20150011782A1
公开（公告）日：2015-01-08
Disclosed herein is a novel route of synthesis of syn azide epoxide of formula 5, which is used as a common intermediate for asymmetric synthesis of HIV protease inhibitors such as Amprenavir, Fosamprenavir, Saquinavir and formal synthesis of Darunavir and Palinavir obtained by Cobalt-catalyzed hydrolytic kinetic resolution of racemic anti-(2SR,3SR)-3-azido-4-phenyl-1,2-epoxybutane (azido-epoxide).
[EN] SPIROCYCLIC HETEROCYCLE COMPOUNDS USEFUL AS HIV INTEGRASE INHIBITORS<br/>[FR] COMPOSÉS HÉTÉROCYCLIQUES SPIROCYCLIQUES UTILES COMME INHIBITEURS DU VIH
申请人：MERCK SHARP & DOHME
公开号：WO2016094198A1
公开（公告）日：2016-06-16
The present invention relates to Spirocyclic Heterocycle Compounds of Formula (I): (I) and pharmaceutically acceptable salts thereof, wherein A, B, X, R1, R2, R3 and R4 are as defined herein. The present invention also relates to compositions comprising at least one Spirocyclic Heterocycle Compound, and methods of using the Spirocyclic Heterocycle Compounds for treating or preventing HIV infection in a subject.
[EN] DERIVATIVES OF AMANITA TOXINS AND THEIR CONJUGATION TO A CELL BINDING MOLECULE<br/>[FR] DÉRIVÉS DE TOXINES D'AMANITES ET LEUR CONJUGAISON À UNE MOLÉCULE DE LIAISON CELLULAIRE
申请人：HANGZHOU DAC BIOTECH CO LTD
公开号：WO2017046658A1
公开（公告）日：2017-03-23
Derivatives of Amernita toxins of Formula (I), wherein, formula (a) R 1, R 2, R 3, R 4, R 5, R 6, R 7, R 8, R 9, R 10, X, L, m, n and Q are defined herein. The preparation of the derivatives. The therapeutic use of the derivatives in the targeted treatment of cancers, autoimmune disorders, and infectious diseases.
[EN] A CONJUGATE OF A CYTOTOXIC AGENT TO A CELL BINDING MOLECULE WITH BRANCHED LINKERS<br/>[FR] CONJUGUÉ D'UN AGENT CYTOTOXIQUE À UNE MOLÉCULE DE LIAISON CELLULAIRE AVEC DES LIEURS RAMIFIÉS
申请人：HANGZHOU DAC BIOTECH CO LTD
公开号：WO2020257998A1
公开（公告）日：2020-12-30
Provided is a conjugation of cytotoxic drug to a cell-binding molecule with a side-chain linker. It provides side-chain linkage methods of making a conjugate of a cytotoxic molecule to a cell-binding ligand, as well as methods of using the conjugate in targeted treatment of cancer, infection and immunological disorders.
[EN] CROSS-LINKED PYRROLOBENZODIAZEPINE DIMER (PBD) DERIVATIVE AND ITS CONJUGATES<br/>[FR] DÉRIVÉ DE DIMÈRE DE PYRROLOBENZODIAZÉPINE RÉTICULÉ (PBD) ET SES CONJUGUÉS
申请人：HANGZHOU DAC BIOTECH CO LTD
公开号：WO2020006722A1
公开（公告）日：2020-01-09
A novel cross-linked cytotoxic agents, pyrrolobenzo-diazepine dimer (PBD) derivatives, and their conjugates to a cell-binding molecule, a method for preparation of the conjugates and the therapeutic use of the conjugates.
