Publications by authors named "Summerfield S"

Article Synopsis
  • The term "bioanalytical" now covers a wider range of analytical outputs, including drug concentration data and evidence of drug interactions within the body, such as immunogenicity and pathway effects.
  • The Bioanalytical Hub model integrates various bioanalytical support services, focusing on multiple endpoints like pharmacokinetics and biomarkers while using diverse analytical methods.
  • This integrated approach maximizes the use of lab instruments, improves workforce flexibility, and enhances data analysis, reducing the need for multiple transitions as assays progress from exploratory stages to fully validated endpoints.
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The 15th edition of the Workshop on Recent Issues in Bioanalysis (15th WRIB) was held on 27 September to 1 October 2021. Even with a last-minute move from in-person to virtual, an overwhelmingly high number of nearly 900 professionals representing pharma and biotech companies, contract research organizations (CROs), and multiple regulatory agencies still eagerly convened to actively discuss the most current topics of interest in bioanalysis. The 15th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccines.

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Purpose: More than 15 years have passed since the first description of the unbound brain-to-plasma partition coefficient (K) by Prof. Margareta Hammarlund-Udenaes, which was enabled by advancements in experimental methodologies including cerebral microdialysis. Since then, growing knowledge and data continue to support the notion that the unbound (free) concentration of a drug at the site of action, such as the brain, is the driving force for pharmacological responses.

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The Free Drug Hypothesis is a well-established concept within the scientific lexicon pervading many areas of Drug Discovery and Development, and yet it is poorly defined by virtue of many variations appearing in the literature. Clearly, unbound drug is in dynamic equilibrium with respect to absorption, distribution, metabolism, elimination, and indeed, interaction with the desired pharmacological target. Binding interactions be they specific (e.

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Reducing the required frequence of drug dosing can improve the adherence of patients to chronic treatments. Hence, drugs with longer half-lives are highly desirable. One of the most promising approaches to extend the half-life of drugs is conjugation to human serum albumin (HSA).

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The 14 edition of the Workshop on Recent Issues in Bioanalysis (14 WRIB) was held virtually on June 15-29, 2020 with an attendance of over 1000 representatives from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations, and regulatory agencies worldwide. The 14 WRIB included three Main Workshops, seven Specialized Workshops that together spanned 11 days in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccine. Moreover, a comprehensive vaccine assays track; an enhanced cytometry track and updated Industry/Regulators consensus on BMV of biotherapeutics by Mass Spectrometry (hybrid assays, LCMS and HRMS) were special features in 2020.

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Biography Having studied for a PhD and postdoctoral fellowship in proteomics Scott moved into the field of regulated Bioanalysis in 1997 when joining SmithKline Beecham. In 2001, Scott moved to Neuroscience Drug Discovery to lead a bioanalytical team supporting PK, DMPK and metabolite id work. In 2009, he returned to the regulated bioanalytical group, initially as a Section Leader and subsequently as Site Head and currently as WW Head of Bioanalysis at GSK.

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The 2018 12 Workshop on Recent Issues in Bioanalysis (12th WRIB) took place in Philadelphia, PA, USA on April 9-13, 2018 with an attendance of over 900 representatives from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations and regulatory agencies worldwide. WRIB was once again a 5-day full immersion in bioanalysis, biomarkers and immunogenicity. As usual, it was specifically designed to facilitate sharing, reviewing, discussing and agreeing on approaches to address the most current issues of interest including both small- and large-molecule bioanalysis involving LC-MS, hybrid ligand binding assay (LBA)/LC-MS and LBA/cell-based assays approaches.

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Quantitative bioanalytical data are crucial in pharmaceutical research and development, allowing project teams to make informed scientific decisions on the progression of candidate molecules to medicines. Many challenges are often encountered during the bioanalysis of drugs in biological matrices which require resolution in a timely manner. In this publication, guidance is provided to bioanalytical scientists on how to identify potential problems before they become an obstacle for the drug development and to share our experiences dealing some of most common problems encountered in the bioanalytical laboratory.

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Outcomes of incurred sample reanalysis (ISR) studies have been reviewed from a decade of internally supported bioanalysis. From over 1000 bioanalytical pharmacokinetic end points, 26 bioanalytical studies have failed against predefined ISR acceptance criteria, ultimately resulting in the rejection of three partial and two full datasets (instability or preanalytic contamination). The remaining investigations highlighted methodological root causes including unexpected within-study assay variability, inappropriate assay range and sample homogeneity.

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Besides routine pharmacokinetic (PK) parameters, unbound brain-to-blood concentration ratio (K) is an index particularly crucial in drug discovery for central nervous system (CNS) indications. Despite advantages of K from steady state after constant intravenous (i.v.

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Recent years have seen a paradigm shift away from optimizing the brain:blood concentration ratio toward the more relevant brain:blood unbound concentration ratio (K) in CNS drug discovery. Here, we review the recent developments in the in silico and in vitro model systems to predict the K of discovery compounds with special emphasis on the in-vitro-in-vivo correlation. We also discuss clinical 'translation' of rodent K and highlight the future directions for improvement in brain penetration prediction.

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Little is known about the impact of the blood-nerve barrier (BNB) on drug distribution into peripheral nerves. In this study, we examined the peripheral nerve penetration in rats of 11 small-molecule drugs possessing diverse physicochemical and transport properties and ProTx-II, a tarantula venom peptide with molecular mass of 3826 Daltons. Each drug was administered as constant rate intravenous infusion for 6 hours (small molecules) or 24 hours (ProTx-II).

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Aim: Typically, quantitation of biotherapeutics from biological matrices by LC-MS is based on a surrogate peptide approach to determine molecule concentration. Recent efforts have focused on quantitation of the intact protein molecules or larger mass subunits of monoclonal antibodies. To date, there has been limited guidance for large or intact protein mass quantitation for quantitative bioanalysis.

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The 2017 11th Workshop on Recent Issues in Bioanalysis (11th WRIB) took place in Los Angeles/Universal City, California from 3 April 2017 to 7 April 2017 with participation of close to 750 professionals from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations and regulatory agencies worldwide. WRIB was once again a 5-day, weeklong event - A Full Immersion Week of Bioanalysis, Biomarkers and Immunogenicity. As usual, it was specifically designed to facilitate sharing, reviewing, discussing and agreeing on approaches to address the most current issues of interest including both small and large molecule analysis involving LCMS, hybrid LBA/LCMS and ligand-binding assay (LBA) approaches.

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Emerging evidence indicates an important role for the breast cancer resistance protein (BCRP) in limiting brain penetration of substrate drugs. While in vitro transwell assays can provide an indication of BCRP substrate potential, the predictability of these assays in relation to in vivo brain penetration is still under debate. The present study examined the correlation of BCRP membrane protein expression level and transcellular transport activity across Madin-Darby canine kidney (MDCK) II monolayers.

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Circulating drug concentrations (clinical or preclinical) underly many interactions between industry and regulators; expressing safety coverage, pharmacokinetic-pharmacodynamic relationships or defining bioequivalence and dosing regimens. Accurate and precise measurement of these circulating concentrations is pivotal to the evolution and validation of any bioanalytical method that supports regulatory interactions. Since the bioanalyst is presented with a sub-aliquot of sampled biological matrix, how do they ensure this aliquot reflects the concentration in the subject at the time of collection? Here we share experiences from project support (internal and at CROs) that suggests we need to be ever vigilant translating the needs of bioanalysis with those of project teams.

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The 2016 10 Workshop on Recent Issues in Bioanalysis (10 WRIB) took place in Orlando, Florida with participation of close to 700 professionals from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations, and regulatory agencies worldwide. WRIB was once again a 5-day, weeklong event - A Full Immersion Week of Bioanalysis including Biomarkers and Immunogenicity. As usual, it was specifically designed to facilitate sharing, reviewing, discussing and agreeing on approaches to address the most current issues of interest including both small and large molecule analysis involving LCMS, hybrid LBA/LCMS, and LBA approaches, with the focus on biomarkers and immunogenicity.

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