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Zaina P. Qureshi

Bio: Zaina P. Qureshi is an academic researcher from Merck & Co.. The author has contributed to research in topics: Medicine & Medical prescription. The author has an hindex of 15, co-authored 53 publications receiving 847 citations. Previous affiliations of Zaina P. Qureshi include Veterans Health Administration & William Jennings Bryan Dorn VA Medical Center.


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Journal ArticleDOI
TL;DR: In this study, new molecular entities approved by the Food and Drug Administration (FDA) were examined in the USA from 1980 to 2009.
Abstract: Purpose Economic factors, market dynamics, and safety issues are largely responsible for decisions to withdraw pharmaceutical products from the market. In this study, new molecular entities (NMEs) approved by the Food and Drug Administration (FDA) were examined in the USA from 1980 to 2009. Methods Data were obtained from the FDA, Micromedex, Medline, and Lexis-Nexis. Descriptive analyses were used to classify product discontinuations by therapeutic category, time frame for discontinuation, and reason for withdrawal. Results There were 740 NMEs approved by the FDA during the study period. As of 1 December 2010, the number of drugs discontinued was 118 (15.9%). Discontinuations were the highest for antiparasitic products, insecticides, and repellents (6, 33.3% of approvals), systemic hormonal preparations excluding sex hormones and insulins (5, 33.3%), musculo-skeletal system (11, 32.4%), diagnostic agents (16, 28.1%), and anti-infectives for systemic use (27, 25.2%). Safety was the primary reason for withdrawing 26 drugs (3.5% of approvals). Conclusions Approximately one in seven approved NMEs were discontinued from the market in the period of 1980–2009. Less than one-quarter (22%) of the total withdrawals were attributed to safety reasons. An ongoing evaluation of new drugs throughout their product life cycle is important to determine their efficacy, safety, and value to society. Copyright © 2011 John Wiley & Sons, Ltd.

144 citations

Journal ArticleDOI
TL;DR: Oncology biosimilars use is emerging worldwide, with the notable exception of the USA, where several regulatory and cost barriers to biosimilar approval exist.
Abstract: Summary Biological oncology products are integral to cancer treatment, but their high costs pose challenges to patients, families, providers, and insurers. The introduction of biosimilar agents—molecules that are similar in structure, function, activity, immunogenicity, and safety to the original biological drugs—provide opportunities both to improve health-care access and outcomes, and to reduce costs. Several international regulatory pathways have been developed to expedite entry of biosimilars into global marketplaces. The first wave of oncology biosimilar use was in Europe and India in 2007. Oncology biosimilars are now widely marketed in several countries in Europe, and in Australia, Japan, China, Russia, India, and South Korea. Their use is emerging worldwide, with the notable exception of the USA, where several regulatory and cost barriers to biosimilar approval exist. In this Review, we discuss oncology biosimilars and summarise their regulatory frameworks, clinical experiences, and safety concerns.

103 citations

Journal ArticleDOI
TL;DR: A novel expectation-maximization (EM) algorithm is developed for finding the maximum likelihood estimates of the parameters in the proportional hazards model, which uses a monotone spline representation to approximate the unknown nondecreasing cumulative baseline hazard function.
Abstract: The proportional hazards model (PH) is currently the most popular regression model for analyzing time-to-event data. Despite its popularity, the analysis of interval-censored data under the PH model can be challenging using many available techniques. This article presents a new method for analyzing interval-censored data under the PH model. The proposed approach uses a monotone spline representation to approximate the unknown nondecreasing cumulative baseline hazard function. Formulating the PH model in this fashion results in a finite number of parameters to estimate while maintaining substantial modeling flexibility. A novel expectation-maximization (EM) algorithm is developed for finding the maximum likelihood estimates of the parameters. The derivation of the EM algorithm relies on a two-stage data augmentation involving latent Poisson random variables. The resulting algorithm is easy to implement, robust to initialization, enjoys quick convergence, and provides closed-form variance estimates. The performance of the proposed regression methodology is evaluated through a simulation study, and is further illustrated using data from a large population-based randomized trial designed and sponsored by the United States National Cancer Institute.

83 citations

Journal ArticleDOI
01 Feb 2012-Ndt Plus
TL;DR: Danish nephrologists in Denmark unexpectedly identified chronic kidney disease patients with a new syndrome, nephrogenic systemic fibrosis (NSF), and an independent review concluded that the DMA had erred in rescinding gadodiamide's renal insufficiency contraindication in 1998 and that this error was a key factor in the development of NSF in Denmark.
Abstract: Background. In 2006, nephrologists in Denmark unexpectedly identified chronic kidney disease (CKD) patients with a new syndrome, nephrogenic systemic fibrosis (NSF). Subsequently, 1603 NSF patients were reported to the Food and Drug Administration. Sixty hospitals in the USA account for 93% of these cases, and two hospitals in Denmark account for 4% of these reports. We review Denmark’s identification and subsequent rapid eradication of NSF. Methods. NSF reports from clinicians, the Danish Medicines Agency (DMA) and gadolinium-based contrast agents (GBCAs) manufacturers were reviewed (2002–11). Results. In 1994, the DMA approved a non-ionic linear GBCA, gadodiamide (0.1 mmol/kg), for magnetic resonance imagings (MRIs), with a renal insufficiency contraindication. In 1996, 0.3 mmol/kg dosing received DMA approval. In 1998, the DMA removed renal contraindications. In 1997 and 2002, radiologists at Skejby Hospital and Herlev Hospital, respectively, began performing gadodiamide-enhanced magnetic resonance angiography scans (0.3 mmol/kg) of CKD patients. In 2005, Herlev clinicians requested assistance in evaluating etiological causes of NSF occurring among 10 CKD patients who had developed NSF. This investigation, focusing on infectious agents, was inconclusive. In 2006, Herlev clinicians reported that of 108 CKD patients who had received gadodiamide-enhanced MRI, 20 had developed probable NSF. Herlev radiologists voluntarily discontinued administering gadodiamide to all patients and no new NSF cases at Herlev Hospital developed subsequently. After meeting with Herlev radiologists, Skejby radiologists also discontinued administering gadodiamide to all patients. In 2007, the European Medicines Agency and the DMA contraindicated gadodiamide administration to CKD patients. In 2008, in response to these advisories, radiologists at the other 36 Danish hospitals discontinued administering gadodiamide to all patients, following on practices adopted at Skejby and Herlev Hospitals. In 2009, clinicians at Skejby Hospital reported that a look-back survey identified 33 CKD patients with NSF developing after undergoing GBCA-enhanced MRIs between 1999 and 2007. In 2010, an independent review, commissioned by the Minister of Health, concluded that the DMA had erred in rescinding gadodiamide’s renal insufficiency contraindication in 1998 and that this error was a key factor in the development of NSF in Denmark. In 2011, three NSF cases associated with macrocyclic GBCA-associated NSF and three NSF patients with Stages 3 and 4 CKD disease from Skejby Hospital were reported. Conclusion. A confluence of factors led to the development and eradication of NSF in Denmark.

77 citations

Journal ArticleDOI
TL;DR: Severe deficiency of ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) was present in 80% and antibodies to 100% of these TTP patients on ticlopidine, 0% of the patients with clopidogrel- associated TTP, and an unknown percentage of patients with prasugrel-associated TTP.
Abstract: Thienopyridine-derivatives (ticlopidine, clopidogrel, and prasugrel) are the primary antiplatelet agents. Thrombotic thrombocytopenic purpura (TTP) is a rare drug-associated syndrome, with the thienopyridines being the most common drugs implicated in this syndrome. We reviewed 20 years of information on clinical, epidemiologic, and laboratory findings for thienopyridine-associated TTP. Four, 11, and 11 cases of thienopyridine-associated TTP were reported in the first year of marketing of ticlopidine (1989), clopidogrel (1998), and prasugrel (2010), respectively. As of 2011, the FDA received reports of 97 ticlopidine-, 197 clopidogrel-, and 14 prasugrel-associated TTP cases. Severe deficiency of ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) was present in 80% and antibodies to 100% of these TTP patients on ticlopidine, 0% of the patients with clopidogrel-associated TTP (p < 0.05), and an unknown percentage of patients with prasugrel-associated TTP. TTP is associated with use of each of the three thienopyridines, although the mechanistic pathways may differ.

69 citations


Cited by
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Journal ArticleDOI
TL;DR: The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.
Abstract: The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating, and categorizing indications for the evidence-based use of therapeutic apheresis in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the Committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Seventh Edition of the JCA Special Issue continues to maintain this methodology and rigor to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Seventh Edition, like its predecessor, has consistently applied the category and grading system definitions in the fact sheets. The general layout and concept of a fact sheet that was used since the fourth edition has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis in a specific disease entity. The Seventh Edition discusses 87 fact sheets (14 new fact sheets since the Sixth Edition) for therapeutic apheresis diseases and medical conditions, with 179 indications, which are separately graded and categorized within the listed fact sheets. Several diseases that are Category IV which have been described in detail in previous editions and do not have significant new evidence since the last publication are summarized in a separate table. The Seventh Edition of the JCA Special Issue serves as a key resource that guides the utilization of therapeutic apheresis in the treatment of human disease. J. Clin. Apheresis 31:149-162, 2016. © 2016 Wiley Periodicals, Inc.

1,691 citations

Journal ArticleDOI
TL;DR: ChEMBL is an open large-scale bioactivity database that includes the annotation of assays and targets using ontologies, the inclusion of targets and indications for clinical candidates, addition of metabolic pathways for drugs and calculation of structural alerts.
Abstract: ChEMBL is an open large-scale bioactivity database (https://www.ebi.ac.uk/chembl), previously described in the 2012 and 2014 Nucleic Acids Research Database Issues. Since then, alongside the continued extraction of data from the medicinal chemistry literature, new sources of bioactivity data have also been added to the database. These include: deposited data sets from neglected disease screening; crop protection data; drug metabolism and disposition data and bioactivity data from patents. A number of improvements and new features have also been incorporated. These include the annotation of assays and targets using ontologies, the inclusion of targets and indications for clinical candidates, addition of metabolic pathways for drugs and calculation of structural alerts. The ChEMBL data can be accessed via a web-interface, RDF distribution, data downloads and RESTful web-services.

1,601 citations

Journal ArticleDOI
TL;DR: A comprehensive longitudinal review of AstraZeneca's small-molecule drug projects from 2005 to 2010 allowed us to establish a framework based on the five most important technical determinants of project success and pipeline quality, which are described as the five 'R's'.
Abstract: Maintaining research and development (R&D) productivity at a sustainable level is one of the main challenges currently facing the pharmaceutical industry. In this article, we discuss the results of a comprehensive longitudinal review of AstraZeneca's small-molecule drug projects from 2005 to 2010. The analysis allowed us to establish a framework based on the five most important technical determinants of project success and pipeline quality, which we describe as the five 'R's: the right target, the right patient, the right tissue, the right safety and the right commercial potential. A sixth factor - the right culture - is also crucial in encouraging effective decision-making based on these technical determinants. AstraZeneca is currently applying this framework to guide its R&D teams, and although it is too early to demonstrate whether this has improved the company's R&D productivity, we present our data and analysis here in the hope that it may assist the industry overall in addressing this key challenge.

1,003 citations

Journal ArticleDOI
TL;DR: This Sixth Edition of the ASFA Special Issue has further improved the process of using evidence‐based medicine in the recommendations by consistently applying the category and GRADE system definitions, but eliminating the “level of evidence” criteria.
Abstract: The American Society for Apheresis (ASFA) JCA Special Issue Writing Committee is charged with reviewing, updating and categorizating indications for therapeutic apheresis. Beginning with the 2007 ASFA Special Issue (Fourth Edition), the committee has incorporated systematic review and evidence‐based approach in the grading and categorization of indications. This Sixth Edition of the ASFA Special Issue has further improved the process of using evidence‐based medicine in the recommendations by consistently applying the category and GRADE system definitions, but eliminating the “level of evidence” criteria (from the University HealthCare Consortium) utilized in prior editions given redundancy between GRADE and University HealthCare Consortium systems. The general layout and concept of a fact sheet that was utilized in the Fourth and Fifth Editions, has been largely maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis in a specific disease entity. This article consists of 78 fact sheets (increased from 2010) for therapeutic indications in ASFA categories I through IV, with many diseases categorized having multiple clinical presentations/situations which are individually graded and categorized. J. Clin. Apheresis 28:145–284, 2013. © 2013 Wiley Periodicals, Inc.

590 citations

Journal ArticleDOI
TL;DR: The history, clinical features and prevalence of nephrogenic systemic fibrosis and the current understanding of its pathophysiology are reviewed and the risk factors for NSF are discussed and prophylactic measures are recommended.
Abstract: Purpose To update the guidelines of the Contrast Media Safety Committee (CMSC) of the European Society of Urogenital Radiology (ESUR) on nephrogenic systemic fibrosis and gadolinium-based contrast media.

386 citations