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2.
Adv Exp Med Biol ; 856: 33-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27671719

RESUMO

Animal studies may be carried out to support first administration of a new medicinal product to either humans or the target animal species, or before performing clinical trials in even larger populations, or before marketing authorisation, or to control quality during production. Ethical and animal welfare considerations require that animal use is limited as much as possible. Directive 2010/63/EU on the protection of animals used for scientific purposes unambiguously fosters the application of the principle of the 3Rs when considering the choice of methods to be used.As such, today, the 3Rs are embedded in the relevant regulatory guidance both at the European (European Medicines Agency (EMA)) and (Veterinary) International Conference on Harmonization ((V)ICH) levels. With respect to non-clinical testing requirements for human medicinal products, reduction and replacement of animal testing has been achieved by the regulatory acceptance of new in vitro methods, either as pivotal, supportive or exploratory mechanistic studies. Whilst replacement of animal studies remains the ultimate goal, approaches aimed at reducing or refining animal studies have also been routinely implemented in regulatory guidelines, where applicable. The chapter provides an overview of the implementation of 3Rs in the drafting of non-clinical testing guidelines for human medicinal products at the level of the ICH. In addition, the revision of the ICH S2 guideline on genotoxicity testing and data interpretation for pharmaceuticals intended for human use is discussed as a case study.In October 2010, the EMA established a Joint ad hoc Expert Group (JEG 3Rs) with the mandate to improve and foster the application of 3Rs principles to the regulatory testing of medicinal products throughout their lifecycle. As such, a Guideline on regulatory acceptance of 3R testing approaches was drafted that defines regulatory acceptance and provides guidance on the scientific and technical criteria for regulatory acceptance of 3R testing approaches, including a process for collection of real-life data (safe harbour). Pathways for regulatory acceptance of 3R testing approaches are depicted and a new procedure for submission and evaluation of a proposal for regulatory acceptance of 3R testing approaches is described.


Assuntos
Alternativas aos Testes com Animais/métodos , Descoberta de Drogas , Testes de Toxicidade/métodos , Animais , Testes de Carcinogenicidade/métodos , Guias como Assunto , Humanos , Testes de Mutagenicidade/métodos , Reprodução/efeitos dos fármacos , Toxicocinética
3.
Regul Toxicol Pharmacol ; 73(1): 361-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26232707

RESUMO

Cancer presents a major healthcare challenge worldwide, with several millions new cases a year, and represents a therapeutic area with a high need for new drugs. To respond to this, the parties of the International Conference for Harmonization agreed in 2007 to develop a guideline on nonclinical requirements for oncology therapeutics' development (ICH S9), which came into effect in early 2010. This guideline includes recommendations to facilitate and accelerate the development and marketing of cancer therapeutic agents for serious and life threatening malignancies and aims to address this need through a refinement and a reduction in the use of experimental animals, following the 3Rs principles. To assess the impact of ICH S9 on drug development and reduction of animal use, we performed an analysis of Marketing Authorization Applications at the European Medicines Agency relevant to the period in which the development of the guideline was approaching the final steps and its early implementation period. From the analysis performed, a consistent trend towards a decrease in the average number of non-clinical studies performed (-40.7%) and number of animals used per development program (-58.1%) for new chemical entities has been detected, highlighting increasing compliance by companies to the recommendations of ICH S9.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/normas , Descoberta de Drogas/normas , Neoplasias/tratamento farmacológico , Experimentação Animal/normas , Animais , Animais de Laboratório , Aprovação de Drogas/métodos , Indústria Farmacêutica/métodos , Guias como Assunto , Cooperação Internacional
4.
Histochem J ; 34(3-4): 139-51, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12495220

RESUMO

In search of factors that regulate the phenotype of the peroxisomal compartment in wild-type liver parenchymal cells, we compared hepatocyte polarity to peroxisome differentiation, using adult liver as the standard. Differentiation parameters were evaluated in a three-dimensional culture model (spheroid), in 'sandwich' and monolayer primary hepatocyte cultures, and in 15.5 and 18.5-day-old foetal rat liver. Peroxisomes, studied by immunohistochemistry, enzyme histochemistry, and catalase specific activity, were better differentiated depending on foetal age (day 18.5 > day 15.5) and culture type (spheroid > sandwich > monolayer). The hepatocyte polarity markers ATP-, ADP-, and AMP-hydrolysing activities were, in all models, mislocalized at the lateral plasma membrane, whereas in contrast the multidrug resistance-associated protein 2 (mrp2) antigen was always correctly immunolocalized at the apical membrane domain. In cultures, the correct secretion of fluorescein (mrp2-mediated) into bile canaliculi was observed. Bile canaliculi (branching, ultrastructure and immunolocalization of the tight-junction associated protein ZO-1), were better differentiated in 18.5 than in 15.5-day-old foetal liver and in spheroid > sandwich > monolayer cultures. Our results show a parallelism between changes of the peroxisomal compartment and bile canalicular structure together with mrp2-mediated secretory function. Distinct polarization characteristics do not necessarily change simultaneously, suggesting different regulatory mechanisms.


Assuntos
Polaridade Celular/fisiologia , Hepatócitos/fisiologia , Proteínas de Membrana Transportadoras , Peroxissomos/fisiologia , Difosfato de Adenosina/metabolismo , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Albuminas/metabolismo , Animais , Canalículos Biliares/citologia , Canalículos Biliares/fisiologia , Canalículos Biliares/ultraestrutura , Catalase/metabolismo , Células Cultivadas , Feminino , Fluoresceína , Hepatócitos/ultraestrutura , Imuno-Histoquímica , Glicogênio Hepático/metabolismo , Proteínas de Membrana/metabolismo , Microscopia Eletrônica , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Peroxissomos/ultraestrutura , Fosfoproteínas/metabolismo , Gravidez , Ratos , Junções Íntimas/ultraestrutura , Proteína da Zônula de Oclusão-1
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