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John R. Crison

Other affiliations: Pfizer, Simulations Plus, Inc.
Bio: John R. Crison is an academic researcher from Bristol-Myers Squibb. The author has contributed to research in topics: Dissolution testing & Solubility. The author has an hindex of 21, co-authored 39 publications receiving 6608 citations. Previous affiliations of John R. Crison include Pfizer & Simulations Plus, Inc..

Papers
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Journal ArticleDOI
TL;DR: A biopharmaceutics drug classification scheme for correlating in vitro drug product dissolution and in vivo bioavailability is proposed based on recognizing that drug dissolution and gastrointestinal permeability are the fundamental parameters controlling rate and extent of drug absorption.
Abstract: A biopharmaceutics drug classification scheme for correlating in vitro drug product dissolution and in vivo bioavailability is proposed based on recognizing that drug dissolution and gastrointestinal permeability are the fundamental parameters controlling rate and extent of drug absorption. This analysis uses a transport model and human permeability results for estimating in vivo drug absorption to illustrate the primary importance of solubility and permeability on drug absorption. The fundamental parameters which define oral drug absorption in humans resulting from this analysis are discussed and used as a basis for this classification scheme. These Biopharmaceutic Drug Classes are defined as: Case 1. High solubility-high permeability drugs, Case 2. Low solubility-high permeability drugs, Case 3. High solubility-low permeability drugs, and Case 4. Low solubility-low permeability drugs. Based on this classification scheme, suggestions are made for setting standards for in vitro drug dissolution testing methodology which will correlate with the in vivo process. This methodology must be based on the physiological and physical chemical properties controlling drug absorption. This analysis points out conditions under which no in vitro-in vivo correlation may be expected e.g. rapidly dissolving low permeability drugs. Furthermore, it is suggested for example that for very rapidly dissolving high solubility drugs, e.g. 85% dissolution in less than 15 minutes, a simple one point dissolution test, is all that may be needed to insure bioavailability. For slowly dissolving drugs a dissolution profile is required with multiple time points in systems which would include low pH, physiological pH, and surfactants and the in vitro conditions should mimic the in vivo processes. This classification scheme provides a basis for establishing in vitro-in vivo correlations and for estimating the absorption of drugs based on the fundamental dissolution and permeability properties of physiologic importance.

5,049 citations

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TL;DR: This study presents a meta-analysis of the phytochemical properties of seven novel drugs that have been developed over a period of several years and show promise in terms of protecting against adverse events and promoting drug safety.
Abstract: Contributors Jean-Marc Aiache, Nobuo Aoyagi, Dennis Bashaw, Cynthia Brown, William Brown, Diane Burgess, John Crison, Patrick DeLuca, Ruzica Djerki, Jennifer Dressman, Thomas Foster, Kirsti Gjellan, Vivian Gray, Ajaz Hussain, Tom Ingallinera, James Klancke, Johannes Kraemer, Henning Kristensen, Kofi Kumi, Christian Leuner, Jobst Limberg, Petra Loos, Lenny Margulis, Patrick Marroum, Helga Moeller, Bernd Mueller, Martin Mueller-Zsigmondy, Ngozi Okafo, Larry Ouderkirk, Shravan Parsi, Saeed Qureshi, Joseph Robinson, Vinod Shah, Martin Siewert, Ramana Uppoor, and Roger Williams. Aventis, Frankfurt, Germany JW Goethe University, Frankfurt, Germany Eli Lilly and Company, Indianapolis, IN Office of Pharmaceutical Science, Center for Drug Evaluation and Research, US Food and Drug Administration, Rockville, MD Universite d'Auvergne, Clermont-Ferrand Cedex, France National Institute of Health Sciences, Division of Drugs, Tokyo, Japan US Pharmacopeia, Rockville, MD University of Connecticut, Storrs Mansfield, CT Pfizer, Inc, La Jolla, CA University of Kentucky, Lexington, KY Novartis Pharma, Basel, Switzerland AstraZeneca, Sodertalje, Sweden V.A. Gray Consulting, Inc, Hockessin, DE AAI International, Charleston, SC CIMA Laboratories, Inc, Minneapolis, MN Laboratory and Quality Services, Eschborn, Germany University of Copenhagen, Denmark Bundesinstitut fur Arzneimittel, Bonn, Germany Aventis Pharmaceuticals, Bridgewater, NJ Pfizer, Groton, CT Zentrallaboratorium Deutscher Apotheker, Eschborn, Germany Kiel University, Kiel, Germany Alza Corporation, Mountain View, CA DPT Laboratories, Ltd, San Antonio, TX Health Protection Branch, Ottawa, Canada University of Wisconsin, WI

371 citations

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TL;DR: This review focuses on the dynamic models, which predict both the fraction of dose absorbed and the rate of drug absorption and can be related to pharmacokinetic models to evaluate plasma concentration profiles.

322 citations

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TL;DR: It was demonstrated that the small intestinal transit flow profile was well characterized by both compartmental transit and dispersion models, but not by the single-compartment model, and it was concluded that the compartmental Transit model might be superior to thesingle-compartments model and less complex than the dispersion model.

220 citations

Journal ArticleDOI
TL;DR: This model may be useful in predicting the dissolution of an ionizable water insoluble drug as a function of pH and surfactant and for establishing in vitro-in vivo correlations, IVIVC, for maintaining bioequivalence of drug products.

162 citations


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Posted Content
TL;DR: Deming's theory of management based on the 14 Points for Management is described in Out of the Crisis, originally published in 1982 as mentioned in this paper, where he explains the principles of management transformation and how to apply them.
Abstract: According to W. Edwards Deming, American companies require nothing less than a transformation of management style and of governmental relations with industry. In Out of the Crisis, originally published in 1982, Deming offers a theory of management based on his famous 14 Points for Management. Management's failure to plan for the future, he claims, brings about loss of market, which brings about loss of jobs. Management must be judged not only by the quarterly dividend, but by innovative plans to stay in business, protect investment, ensure future dividends, and provide more jobs through improved product and service. In simple, direct language, he explains the principles of management transformation and how to apply them.

9,241 citations

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TL;DR: Overall, it is advised that the timing of transporter investigations should be driven by efficacy, safety and clinical trial enrolment questions, as well as a need for further understanding of the absorption, distribution, metabolism and excretion properties of the drug molecule, and information required for drug labelling.
Abstract: Membrane transporters can be major determinants of the pharmacokinetic, safety and efficacy profiles of drugs. This presents several key questions for drug development, including which transporters are clinically important in drug absorption and disposition, and which in vitro methods are suitable for studying drug interactions with these transporters. In addition, what criteria should trigger follow-up clinical studies, and which clinical studies should be conducted if needed. In this article, we provide the recommendations of the International Transporter Consortium on these issues, and present decision trees that are intended to help guide clinical studies on the currently recognized most important drug transporter interactions. The recommendations are generally intended to support clinical development and filing of a new drug application. Overall, it is advised that the timing of transporter investigations should be driven by efficacy, safety and clinical trial enrolment questions (for example, exclusion and inclusion criteria), as well as a need for further understanding of the absorption, distribution, metabolism and excretion properties of the drug molecule, and information required for drug labelling.

2,879 citations

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TL;DR: While the book is a standard fixture in most chemical and physical laboratories, including those in medical centers, it is not as frequently seen in the laboratories of physician's offices (those either in solo or group practice), and I believe that the Handbook can be useful in those laboratories.
Abstract: There is a special reason for reviewing this book at this time: it is the 50th edition of a compendium that is known and used frequently in most chemical and physical laboratories in many parts of the world. Surely, a publication that has been published for 56 years, withstanding the vagaries of science in this century, must have had something to offer. There is another reason: while the book is a standard fixture in most chemical and physical laboratories, including those in medical centers, it is not as frequently seen in the laboratories of physician's offices (those either in solo or group practice). I believe that the Handbook can be useful in those laboratories. One of the reasons, among others, is that the various basic items of information it offers may be helpful in new tests, either physical or chemical, which are continuously being published. The basic information may relate

2,493 citations

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TL;DR: This review discusses the various traditional and novel techniques (such as in situ microencapsulation) of preparing various drug loaded PLGA devices, with emphasis on preparing microparticles.

2,232 citations

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TL;DR: This article presents an overview of nanotechnology for the biologist and discusses the attributes of the novel XPclad((c)) nanoparticle formulation that has shown efficacy in treating solid tumors, single dose vaccination, and oral delivery of therapeutic proteins.

2,155 citations