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An Integrated Experimental Design for the Assessment of Multiple Toxicological End Points in Rat Bioassays.

ABSTRACT: For nearly five decades long-term studies in rodents have been the accepted benchmark for assessing chronic long-term toxic effects, particularly carcinogenicity, of chemicals. The European Food Safety Authority (EFSA) and the World Health Organization (WHO) have pointed out that the current set of internationally utilized test methods capture only some of the potential adverse effects associated with exposures to these agents over the lifetime.In this paper, we propose the adaption of the carcinogenicity bioassay to integrate additional protocols for comprehensive long-term toxicity assessment that includes developmental exposures and long-term outcomes, capable of generating information on a broad spectrum of different end points.An integrated study design based on a stepwise process is described that includes the priority end points of the Economic Co-operation and Development and the National Toxicology Program guidelines on carcinogenicity and chronic toxicity and developmental and reproductive toxicity. Integrating a comprehensive set of relevant toxicological end points in a single protocol represents an opportunity to optimize animal use in accordance with the 3Rs (replacement, reduction and refinement). This strategy has the potential to provide sufficient data on multiple windows of susceptibility of specific interest for risk assessments and public health decision-making by including prenatal, lactational, neonatal exposures and evaluating outcomes over the lifespan.This integrated study design is efficient in that the same generational cohort of rats used for evaluating long-term outcomes can be monitored in satellite parallel experiments to measure biomarkers and other parameters related to system-specific responses including metabolic alterations and endocrine disturbances. Citation: Manservisi F, Babot Marquillas C, Buscaroli A, Huff J, Lauriola M, Mandrioli D, Manservigi M, Panzacchi S, Silbergeld EK, Belpoggi F. 2017. An integrated experimental design for the assessment of multiple toxicological end points in rat bioassays. Environ Health Perspect 125:289-295;?http://dx.doi.org/10.1289/EHP419.

SUBMITTER: Manservisi F

PROVIDER: S-EPMC5332192 | biostudies-other | 2017 Mar

REPOSITORIES: biostudies-other

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An Integrated Experimental Design for the Assessment of Multiple Toxicological End Points in Rat Bioassays.

Manservisi Fabiana F Marquillas Clara Babot CB Buscaroli Annalisa A Huff James J Lauriola Michelina M Mandrioli Daniele D Manservigi Marco M Panzacchi Simona S Silbergeld Ellen K EK Belpoggi Fiorella F

Environmental health perspectives 20160722 3

<h4>Background</h4>For nearly five decades long-term studies in rodents have been the accepted benchmark for assessing chronic long-term toxic effects, particularly carcinogenicity, of chemicals. The European Food Safety Authority (EFSA) and the World Health Organization (WHO) have pointed out that the current set of internationally utilized test methods capture only some of the potential adverse effects associated with exposures to these agents over the lifetime.<h4>Objectives</h4>In this paper ...[more]

PMID: 27448388

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Project description:End points and adverse events (AEs) are collected separately in clinical trials, yet regulatory requirements for serious AE reporting vary across regions, so classifying end points according to seriousness criteria can be useful in global trials. In the Apixaban for Prevention of Acute Ischemic Events 2 (APPRAISE-2) trial, patients with a recent acute coronary syndrome were randomized to apixaban or placebo for the prevention of recurrent ischemic events. Suspected end points (myocardial infarction, stroke, or bleeding) were adjudicated by an independent clinical events classification committee. Safety criteria were collected for suspected end points and AEs. Patient-level event rates per 100 patient-days of follow-up, modeled using Poisson regression, explored the influence of region and patient characteristics on event reporting. Overall, 13 909 events were reported by 858 sites in 39 countries; 8.4% (n=1166) were suspected end points, and 91.6% (n=12 743) were AEs. Overall, 66.0% of suspected end points were confirmed by the clinical events classification committee. Most clinical events classification committee-confirmed end points met criteria to be classified as serious (94.0%); many clinical events classification committee-negated end points also did (63.2%), but fewer AEs met seriousness criteria (17.9%). The most common seriousness criterion was hospitalization (79.9%, n=2594). Region explained 28.7% of end point- and 26.4% of serious AE-reporting variation, and patient characteristics explained an additional 25.4% of end point and 13.4% of serious AE variation. Nonserious AE-reporting variation was not explained by adjustment. An integrated collection of end points and serious AEs is feasible in a multinational trial and illustrates the shared characteristics of events. Tailoring event collection to fit the phase and purpose of the trial is achievable and informative. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00831441.

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An Integrated Experimental Design for the Assessment of Multiple Toxicological End Points in Rat Bioassays.

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An Integrated Experimental Design for the Assessment of Multiple Toxicological End Points in Rat Bioassays.

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