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Dive into the research topics where Roger L. Williams is active.

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Featured researches published by Roger L. Williams.


Journal of The American Pharmaceutical Association | 2002

Lack of Medication Dose Uniformity in Commonly Split Tablets

Jaja Teng; Clara K. Song; Roger L. Williams; James E. Polli

OBJECTIVEnTo divide 11 commonly split tablets and evaluate the resulting half-tablets for content uniformity.nnnDESIGNnPre-post comparison.nnnSETTINGnLaboratory.nnnINTERVENTIONSnA trained individual split tablets of 11 products using a single-edged razor blade and 3 products by hand alone.nnnMAIN OUTCOME MEASURESnThe Uniformity of Dosage Units test published in the United States Pharmacopeia 24 (USP), which applies to whole tablets, was adapted liberally to assess the dose uniformity of the resulting split tablets.nnnRESULTSnOf the 11 razor-split products, 8 failed the liberal adaptation of the USP uniformity test. No visible tablet features (e.g., scoring) predisposed a products split tablets to pass or fail the uniformity test. All three hand-split tablets failed the uniformity test and yielded worse results than did razor-split tablets.nnnCONCLUSIONnThe majority of the 11 drug products we tested, when assessed for their ability to be split into half-tablets of equal dose, failed a liberally interpreted USP uniformity test. The practice of dividing tablets to save costs or to improve a dosage regimen may not cause problems for patients using drugs with low toxicity and relatively flat dose-response relationships, but it is not recommended for patients using drugs with more substantial toxicity and steep dose-response efficacy curves.


Pharmaceutical Research | 2010

Metal Impurities in Food and Drugs

Darrell R. Abernethy; Anthony J. DeStefano; Todd L. Cecil; Kahkashan Zaidi; Roger L. Williams

The major metals of potential health concern found in food, drugs (medicines), and dietary supplements are lead, cadmium, mercury, and arsenic. Other metals, such as chromium, copper, manganese, molybdenum, vanadium, nickel, osmium, rhodium, ruthenium, iridium, palladium, and platinum, may be used or introduced during manufacturing and may be controlled in the final article as impurities. Screening for metals in medicines and dietary supplements rarely indicates the presence of toxic metal impurities at levels of concern. The setting of heavy metal limits is appropriate for medicines and is appropriate for supplements when heavy metals are likely or certain to contaminate a given product. Setting reasonable health-based limits for some of these metals is challenging because of their ubiquity in the environment, limitations of current analytical procedures, and other factors. Taken together, compendial tests for metals in food and drugs present an array of issues that challenge compendial scientists.


Nature Biotechnology | 2016

The US regulatory and pharmacopeia response to the global heparin contamination crisis

Anita Y. Szajek; Edward K. Chess; Kristian B. Johansen; Gyöngyi Gratzl; Elaine Gray; David A. Keire; Robert J. Linhardt; Jian Liu; Tina S. Morris; Barbara Mulloy; Moheb Nasr; Zachary Shriver; Pearle Torralba; Christian Viskov; Roger L. Williams; Janet Woodcock; Wesley Workman; Ali Al-Hakim

The contamination of the widely used lifesaving anticoagulant drug heparin in 2007 has drawn renewed attention to the challenges that are associated with the characterization, quality control and standardization of complex biological medicines from natural sources. Heparin is a linear, highly sulfated polysaccharide consisting of alternating glucosamine and uronic acid monosaccharide residues. Heparin has been used successfully as an injectable antithrombotic medicine since the 1930s, and its isolation from animal sources (primarily porcine intestine) as well as its manufacturing processes have not changed substantially since its introduction. The 2007 heparin contamination crisis resulted in several deaths in the United States and hundreds of adverse reactions worldwide, revealing the vulnerability of a complex global supply chain to sophisticated adulteration. This Perspective discusses how the US Food and Drug Administration (FDA), the United States Pharmacopeial Convention (USP) and international stakeholders collaborated to redefine quality expectations for heparin, thus making an important natural product better controlled and less susceptible to economically motivated adulteration.


Pharmaceutical Research | 2002

Chemistry, Manufacturing, and Controls Information in NDAs and ANDAs, Supplements, Annual Reports, and Other Regulatory Filings

Eric Sheinin; Roger L. Williams

Advice to the pharmaceutical industry regarding the chemistry, manufacturing, and controls and microbiology (sterility assurance) information to be included in regulatory submissions to the Center for Drug Evaluation and Research (CDER) can be found in the pertinent statutes, regulations, and guidances. The primary statute is the Federal Food, Drug and Cosmetic Act (the Act); applicable regulations appear in 21 CFR 312 and 314. Neither the Act nor the regulations provide sufficient detail on the information that should be included in these submissions. Over the past 14 years CDER has issued a series of guidelines and guidances that provide specific detail related to the recommended filing mechanisms and information that CDER expects applicants to provide. Some of these guidances are applicable to original submissions and some are applicable to post-approval changes. This article will provide an overview of The Act, the pertinent regulations, and the pre- and post-approval guidances.


Journal of Near Infrared Spectroscopy | 2009

A Comparison of near Infrared Method Development Approaches Using a Drug Product on Different Spectrophotometers and Chemometric Software Algorithms

Assad Kazeminy; Saheed Hashemi; Roger L. Williams; Gary E. Ritchie; Ronald Rubinovitz; Sumit Sen

It is well known that spectral variability in near infrared (NIR) spectroscopy can be attributed to the analyst, sample, sample positioning, instrument configuration and software (in both algorithm formats and structures used as well as in the execution of data pre-treatment and analysis). It is often acknowledged that the single largest factor impacting NIR results is sample presentation. However, what is obvious but not often acknowledged is that there are instrumental and software differences as well. These differences, evident in the quality of the spectra, may impact the chemometrics that are subsequently performed and, possibly, the results obtained from the multivariate statistical models. In order to investigate just what are these sources of variability, and just how much these variations may impact the results of the multivariate models for predicting the identification of pharmaceutical dosage forms, a study has been conducted. To the authors knowledge, no other systematic study of this kind has been published. In this study, we are interested in learning what variability, if any, the choices for instrument and software have on the development of a NIR method for the identification of pharmaceutical dosage forms. Furthermore, we would like to learn what and how do the choices made early on in the experimental design impact the final quality of the spectra and the resulting multivariate models obtained from these spectra. A study protocol was designed, using a common data set consisting of four formulations of Ibuprofen, involving three investigating parties, namely, US FDA, USP and Irvine Pharmaceutical Services and using three NIR instruments, namely (listed in alphabetical order), a Bruker spectrometer, a Büchi spectrometer and a Foss spectrometer. Based on the results and despite differences in instrument configuration [dispersive or Fourier Transform (FT)], number of spectral data points, principal components analysis (PCA) or factorisation algorithms, and validation modelling approach, exact and accurate spectroscopic results can be achieved using NIR spectroscopy for discriminate analysis. More importantly, this study shows that the same NIR method spectral range and pre-treatment parameters can be used, and that nearly the same multivariate models can be obtained, despite instrumental and software differences, to accurately predict the identity of pharmaceutical dosage forms.


Dissolution Technologies | 2008

USP Responses to Comments on Stimuli Article, "Proposed Change to Acceptance Criteria for Dissolution Performance Verification Testing"

Walter W. Hauck; Todd L. Cecil; William Brown; Darrell R. Abernethy; William F. Koch; Roger L. Williams

Pharmacopeial Forum 33(3) [May–June 2007] included a Stimuli article titled “Proposed Change to Acceptance Criteria for Dissolution Performance Verification Testing.” This Stimuli article proposed changing the form of the acceptance criteria for the Performance Verification Test (PVT) associated with USP Dissolution to make the PVT consistent with the International Organization for Standardization’s recommendations for proficiency testing. The article elicited five comments, which are abstracted here with USP responses.


Aaps Journal | 2014

Progressively Reducing Regulatory Burden

Vinod P. Shah; Todd L. Cecil; Srini V. Srinivasan; Roger L. Williams

Principles of dissolution science have been applied to allow waiver of in vivo bioequivalence studies for oral immediate release solid dosage forms, providing certain stipulations are met. This approach reduces regulatory burden without sacrificing product quality and performance requirements that assure continuing equivalence. These principles are broadly applicable to other dosage forms and routes of administration. In this article, we postulate a further opportunity, which relies on a determination of “optimal performance” for nonsolution orally administered drug products. The determination can be applied to certain highly soluble and rapidly dissolving drug products without further study, paving the way possibly for even further reductions in regulatory burden.


Aaps Journal | 2014

Role of Public Standards in the Safety and Efficacy of Biologic Medicines

Roger L. Williams; Adrian Bristow; Walter W. Hauck; V. Srini Srinivasan; Tina S. Morris; Fouad Atouf; Michael R. Ambrose; Koduru V. Surendranath; Ranjan Chakrabarty; Krishna Menon

In this report, we emphasize the importance of public monographs with reference materials, coupled with careful process and change control and attention to GMPs, as a means of advancing access to good quality, safe, and effective medicines, with emphasis on available and incoming biologic medicines. With adequate control of articles covered by a monograph, these public standards can form the basis for a global public quality platform that covers reference products, non-interchangeable reference products, biosimilars, and interchangeable biosimilars. Working collaboratively with all stakeholders, new approaches allow these public standards to emerge nationally and globally in a timely way. Yet, there are increasing limitations in the availability of public standards for biologic medicines, which may reverse many decades of progress. Solutions are considered in this report.


Dissolution Technologies | 2009

Description of the Upcoming Change in Data Analysis for USP Dissolution Performance Verification Tests

Walter W. Hauck; Anthony J. DeStefano; William Brown; Erika S. Stippler; Darrell R. Abernethy; Roger L. Williams; Thomas S. Foster; James E. Polli; Diane J. Burgess; G. Bryan Crist; Mario A. González; Vivian A. Gray; Johannes Kraemer; Lewis J. Leeson; Alan F. Parr; Leon Shargel; Eli Shefter; W. Craig Simon; Nhan L. Tran; Clarence T. Ueda

As part of its evaluation of the performance verification tests used periodically to affirm the integrity of the USP Performance test when General Chapter Dissolution is relied upon, the Biopharmaceutics Expert Committee of the Council of Experts, working with staff, decided to change the form of the accept/reject decision from one based on the result for each tablet to one based on the mean and coefficient of variation of results from a set of tablets. This paper describes the new approach. The paper also describes an implementation period for the approach, coupled with a period during which USP will discontinue use of the Salicylic Acid tablet in a performance verification test.


The Journal of Allergy and Clinical Immunology | 2002

A methacholine challenge dose-response study for development of a pharmacodynamic bioequivalence methodology for albuterol metered-dose inhalers

Peter S. Creticos; Wallace P. Adams; Brent G. Petty; Lionel D. Lewis; Gur Jai Pal Singh; Arouna P. Khattignavong; Justina A. Molzon; Marilyn N. Martinez; Paul S. Lietman; Roger L. Williams

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Darrell R. Abernethy

Food and Drug Administration

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Walter W. Hauck

United States Pharmacopeial Convention

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William F. Koch

United States Pharmacopeial Convention

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Tina S. Morris

United States Pharmacopeial Convention

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Todd L. Cecil

United States Pharmacopeial Convention

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Anita Y. Szajek

United States Pharmacopeial Convention

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Anthony J. DeStefano

United States Pharmacopeial Convention

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William Brown

United States Pharmacopeial Convention

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