Early clinical drug product shelf-life setting using accelerated predictive stability and metabolite data for impurity qualification: A case study.

This case study demonstrates how knowledge of degradation products together with predictions can establish a lean stability strategy using the accelerated predictive stability (APS) principles. Applying all available data for AZD4831, (R)-1-(2-(1-aminoethyl)-4-chlorobenzyl)-2-thioxo-2,3-dihydro-1H-pyrrolo[3,2-d]pyrimidin-4(5H)-one, a reliable predictive model was developed despite minor differences in technical batch tablet compositions. Early forced degradation studies were performed to map potential degradation pathways.

In Vivo Metabolite Profiles of an -Acetylgalactosamine-Conjugated Antisense Oligonucleotide AZD8233 Using Liquid Chromatography High-Resolution Mass Spectrometry: A Cross-Species Comparison in Animals and Humans.

AZD8233, a liver-targeting antisense oligonucleotide (ASO), inhibits subtilisin/kexin type 9 protein synthesis. It is a phosphorothioated 3-10-3 gapmer with a central DNA sequence flanked by constrained 2'--ethyl 2',4'-bridged nucleic acid (cEt-BNA) wings and conjugated to a triantennary -acetylgalactosamine (GalNAc) ligand at the 5'-end. Herein we report the biotransformation of AZD8233, as given by liver, kidney, plasma and urine samples, after repeated subcutaneous administration to humans, mice, rats, rabbits, and monkeys.

Biotransformation of the Novel Myeloperoxidase Inhibitor AZD4831 in Preclinical Species and Humans.

We report herein an in-depth analysis of the metabolism of the novel myeloperoxidase inhibitor AZD4831 (()-1-(2-(1-aminoethyl)-4-chlorobenzyl)-2-thioxo-2,3-dihydro-1H-pyrrolo[3,2-]pyrimidin-4(5)-one) in animals and human. Quantitative and qualitative metabolite profiling were performed on samples collected from mass balance studies in rats and humans. Exposure of circulating human metabolites with comparable levels in animal species used in safety assessment were also included.

Application of Accelerator Mass Spectrometry to Characterize the Mass Balance Recovery and Disposition of AZD4831, a Novel Myeloperoxidase Inhibitor, following Administration of an Oral Radiolabeled Microtracer Dose in Humans.

This study evaluated the mass balance and disposition of AZD4831, a novel myeloperoxidase inhibitor, in six healthy participants using a C-labeled microtracer coupled with analysis by accelerator mass spectrometry (AMS). A single oral dose of 10 mg C-AZD4831 (14.8 kBq) was administered as a solution, and C levels were quantified by AMS in blood, urine, and feces over 336 hours postdose.

Meeting report of the second European biotransformation workshop.

Challenges and opportunities in the field of biotransformation were presented and discussed at the 2nd European Biotransformation workshop which was conducted virtually in collaboration with the DMDG on November 24/25, 2021. Here we summarise the presentations and discussions from this workshop.The following topics were covered:Regulatory requirements and biotransformation studies for antibody drug conjugates (ADCs) and antisense oligonucleotides (ASOs).

Characterization of Clinical Absorption, Distribution, Metabolism, and Excretion and Pharmacokinetics of Velsecorat Using an Intravenous Microtracer Combined with an Inhaled Dose in Healthy Subjects.

This open-label, single-period study describes the human absorption, distribution, metabolism, excretion, and pharmacokinetics of velsecorat (AZD7594). Healthy subjects received inhaled velsecorat (non-radiolabeled; 720 g) followed by intravenous infusion of carbon 14 (C)-velsecorat (30 g). Plasma, urine, and feces were collected up to 168 hours post-dose.

Meeting report of the first European biotransformation workshop.

1. Challenges and opportunities in the field of biotransformation were presented and discussed at the 1st European Biotransformation workshop which was conducted virtually in collaboration with the DMDG 27 January 2021. Here we summarize the presentations and discussions from this workshop.

Distribution and biotransformation of therapeutic antisense oligonucleotides and conjugates.

Drug properties of antisense oligonucleotides (ASOs) differ significantly from those of traditional small-molecule therapeutics. In this review, we focus on ASO disposition, mainly as characterized by distribution and biotransformation, of nonconjugated and conjugated ASOs. We introduce ASO chemistry to allow the following in-depth discussion on bioanalytical methods and determination of distribution and elimination kinetics at low concentrations over extended periods of time.

Qualification of impurities based on metabolite data.

Regulatory Guidance documents ICH Q3A (R2) and ICH Q3B (R2) state that "impurities that are also significant metabolites present in animal and/or human studies are generally considered qualified". However, no guidance is provided regarding data requirements for qualification, nor is a definition of the term "significant metabolite" provided. An opportunity is provided to define those categories and potentially avoid separate toxicity studies to qualify impurities.

Metabolism of Strained Rings: Glutathione -transferase-Catalyzed Formation of a Glutathione-Conjugated Spiro-azetidine without Prior Bioactivation.

AZD1979 [(3-(4-(2-oxa-6-azaspiro[3.3]heptan-6-ylmethyl)phenoxy)azetidin-1-yl)(5-(4-methoxyphenyl)-1,3,4-oxadiazol-2-yl)methanone] is a melanin-concentrating hormone receptor 1 antagonist designed for the treatment of obesity. In this study, metabolite profiles of AZD1979 in human hepatocytes revealed a series of glutathione-related metabolites, including the glutathionyl, cysteinyl, cysteinylglycinyl, and mercapturic acid conjugates.

Hip To Be Square: Oxetanes as Design Elements To Alter Metabolic Pathways.

Oxetane-containing ring systems are increasingly used in medicinal chemistry programs to modulate druglike properties. We have shown previously that oxetanes are hydrolyzed to diols by human microsomal epoxide hydrolase (mEH). Mapping the enzymes that contribute to drug metabolism is important since an exaggerated dependence on one specific isoenzyme increases the risk of drug-drug interactions with co-administered drugs.

The metabolic fate of fenclozic acid in chimeric mice with a humanized liver.

The metabolic fate of the human hepatotoxin fenclozic acid ([2-(4-chlorophenyl)-1,3-thiazol-4-yl]acetic acid) (Myalex) was studied in normal and bile-cannulated chimeric mice with a humanized liver, following oral administration of 10 mg/kg. This in vivo animal model was investigated to assess its utility to study "human" metabolism of fenclozic acid, and in particular to explore the formation of electrophilic reactive metabolites (RMs), potentially unique to humans. Metabolism was extensive, particularly involving the carboxylic acid-containing side chain.

Oxetane Substrates of Human Microsomal Epoxide Hydrolase.

Oxetanyl building blocks are increasingly used in drug discovery because of the improved drug-like properties they confer on drug candidates, yet little is currently known about their biotransformation. A series of oxetane-containing analogs was studied and we provide the first direct evidence of oxetane hydrolysis by human recombinant microsomal epoxide hydrolase (mEH). Incubations with human liver fractions and hepatocytes were performed with and without inhibitors of cytochrome P450 (P450), mEH and soluble epoxide hydrolase (sEH).

Database Extraction of Metabolite Information of Drug Candidates: Analysis of 27 AstraZeneca Compounds with Human Absorption, Distribution, Metabolism, and Excretion Data.

As part of the drug discovery and development process, it is important to understand the human metabolism of a candidate drug prior to clinical studies. Preclinical in vitro and in vivo experiments across species are conducted to build knowledge concerning human circulating metabolites in preparation for clinical studies; therefore, the quality of these experiments is critical. Within AstraZeneca, all metabolite identification (Met-ID) information is stored in a global database using ACDLabs software.

Significantly Different Covalent Binding of Oxidative Metabolites, Acyl Glucuronides, and S-Acyl CoA Conjugates Formed from Xenobiotic Carboxylic Acids in Human Liver Microsomes.

Xenobiotic carboxylic acids may be metabolized to oxidative metabolites, acyl glucuronides, and/or S-acyl-CoA thioesters (CoA conjugates) in vitro, e.g., in hepatocytes, and in vivo.

Systemic exposure to the metabolites of lesogaberan in humans and animals: a case study of metabolites in safety testing.

During preclinical and early phase clinical studies of drug candidates, exposure to metabolites should be monitored to determine whether safety conclusions drawn from studies in animals can be extrapolated to humans. Metabolites accounting for more than 10% of total exposure to drug-related material (DRM) in humans are of regulatory concern, and for any such metabolites, adequate exposure should be demonstrated in animals before large-scale phase 3 clinical trials are conducted. We have previously identified six metabolites, M1-M6, of the gastroesophageal reflux inhibitor lesogaberan.

Troglitazone metabolism and transporter effects in chimeric mice: a comparison between chimeric humanized and chimeric murinized FRG mice.

1. The biotransformation, hepatic transporter and blood chemistry effects of troglitazone were investigated following 7 days of dosing at 600 mg/kg/day to chimeric murinized or humanized FRG mice, Mo-FRG and Hu-FRG mice, respectively. 2.

Metabolism of xenobiotic carboxylic acids: focus on coenzyme A conjugation, reactivity, and interference with lipid metabolism.

While xenobiotic carboxylic acids (XCAs) have been studied extensively with respect to their enzymatic conversion to potentially reactive acyl glucuronides with implications to drug induced hepatotoxicity, the formation of xenobiotic-S-acyl-CoA thioesters (xenobiotic-CoAs) have been much less studied in spite of data indicating that such conjugates may be equally or more reactive than the corresponding acyl glucuronides. This review addresses enzymes and cell organelles involved in the formation of xenobiotic-CoAs, the reactivity of such conjugates toward biological macromolecules, and in vitro and in vivo methodology to assess consequences of such reactivity. Further, the propensity of xenobiotic-CoAs to interfere with endogenous lipid metabolism, e.

In vitro evaluation of major in vivo drug metabolic pathways using primary human hepatocytes and HepaRG cells in suspension and a dynamic three-dimensional bioreactor system.

Major human specific metabolites, not detected during in vivo and in vitro preclinical studies, may cause unexpected drug interactions and toxicity in human and delays in clinical programs. Thus, reliable preclinical tools for the detection of major human metabolites are of high importance. The aim of this study was to compare major drug metabolic pathways in HepaRG cells, a human hepatoma cell line, to fresh human hepatocytes, cryopreserved human hepatocytes, and human in vivo data.

In vitro approach to assess the potential for risk of idiosyncratic adverse reactions caused by candidate drugs.

Idiosyncratic adverse drug reactions (IADRs) in humans can result in a broad range of clinically significant toxicities leading to attrition during drug development as well as postlicensing withdrawal or labeling. IADRs arise from both drug and patient related mechanisms and risk factors. Drug related risk factors, resulting from parent compound or metabolites, may involve multiple contributory mechanisms including organelle toxicity, effects related to compound disposition, and/or immune activation.

Conference Report: High-resolution MS in drug discovery and development: current applications and future perspectives.

The evolving use of high-resolution MS (HRMS) across the pharmaceutical industry has seen its integrated application into both quantitative and qualitative assays. Through an American Association of Pharmaceutical Scientists (AAPS)/ American Society for Mass Spectrometry (ASMS) workshop, held at AAPS, key scientists from world pharma discussed the feasibility of this new paradigm shift through examples and visions for the future, assessing impact on drug discovery and drug development, as well as educating users new to HRMS in the field. This report details selected talks from the 2-day workshop, with particular emphasis on their impact, as well as personal conclusions around certain topics.