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1.
Eur J Pharm Biopharm ; 74(1): 21-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19013522

RESUMO

The aim of this study was to investigate coating characteristics of push-pull osmotic systems (PPOS) using three-dimensional terahertz pulsed imaging (3D-TPI) and to detect physical alterations potentially impacting the drug release. The terahertz time-domain reflection signal was used to obtain information on both the spatial distribution of the coating thickness and the coating internal physical mapping. The results showed that (i) the thickness distribution of PPOS coating can be non-destructively analysed using 3D-TPI and (ii) internal physical alterations impacting the drug release kinetics were detectable by using the terahertz time-domain signal. Based on the results, the potential benefits of implementing 3D-TPI as quality control analytical tool were discussed.


Assuntos
Preparações de Ação Retardada/química , Imagem Terahertz/métodos , Imageamento Tridimensional/métodos , Cinética , Osmose , Solubilidade , Propriedades de Superfície , Comprimidos/química , Tecnologia Farmacêutica
2.
Eur J Pharm Biopharm ; 73(3): 311-23, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19602438

RESUMO

The number of marketed oral osmotically driven systems (OODS) has doubled in the last 10 years. The main clinical benefits of OODS are their ability to improve treatment tolerability and patient compliance. These advantages are mainly driven by the capacity to deliver drugs in a sustained manner, independent of the drug chemical properties, of the patient's physiological factors or concomitant food intake. However, access to these technologies has been restricted by the crowded patent landscape and manufacturing challenges. In this review article, we intend to give an overview of the OODS development in the last 30 years, detailing the technologies, specific products and their clinical use. General guidance on technology selection is described in light of the recent advances in the field. The clinical performance of these technologies is also discussed, with a focus on food effects and the in vivo-in vitro correlation. Special attention is paid to safety given the controversial case study of Osmosin. Overall, oral osmotically driven systems appear to be a promising technology for product life-cycle strategies.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Preparações Farmacêuticas/administração & dosagem , Tecnologia Farmacêutica/métodos , Administração Oral , Química Farmacêutica , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos/tendências , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Indometacina/administração & dosagem , Bombas de Infusão/tendências , Pressão Osmótica , Tecnologia Farmacêutica/tendências
3.
Int J Pharm ; 376(1-2): 56-62, 2009 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-19383532

RESUMO

Despite more than 30 years of clinical use, only few studies have been published reporting on the release mechanism underlying the drug delivery from push-pull osmotic pumps (PPOP). The aim of this study is to understand which factors have an effect on the drug delivery for modelling the drug release and to develop a mathematical model predictive of the drug release kinetics. The influence of the drug property was tested on two model drugs, isradipine (ISR) and chlorpheniramine (CPA) which are respectively practically insoluble and freely soluble. Results show that, regardless of the drug properties which do not significantly affect the drug delivery, the release kinetics is mainly controlled by four factors, (i) the PEG proportion in the membrane, (ii) the tablet surface area, (iii) the osmotic agent proportion and (iv) the drug layer polymer grade. The influence of each key formulation factors on the release mechanism was investigated defining their applicability range. A mathematical approach was developed to predict the drug delivery kinetics varying the PPOP controlling factors and helps to more efficiently design PPOP.


Assuntos
Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Osmose , Comprimidos/farmacocinética , Clorfeniramina/farmacocinética , Isradipino/farmacocinética , Modelos Estatísticos , Polietilenoglicóis/farmacocinética
4.
Drug Dev Ind Pharm ; 35(4): 433-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18989838

RESUMO

Push-pull osmotic systems have been developed to deliver poorly soluble drugs in a modified-release fashion. The aim of this study was to investigate the influence of the tablet core factors on the drug release kinetics and loadability. The release kinetics was efficiently modulated by varying either the proportion of osmotic agent or the drug layer polymer grade as an alternative to change the membrane characteristics. High osmotic agent proportions and viscous-grade polymers were recommended to formulate high drug loads up to 20% without losing both the release completeness and the zero-order drug release kinetics.


Assuntos
Bloqueadores dos Canais de Cálcio/administração & dosagem , Isradipino/administração & dosagem , Tecnologia Farmacêutica/métodos , Bloqueadores dos Canais de Cálcio/química , Química Farmacêutica , Preparações de Ação Retardada , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Desenho de Equipamento , Excipientes/química , Hidrogel de Polietilenoglicol-Dimetacrilato , Concentração de Íons de Hidrogênio , Isradipino/química , Cinética , Pressão Osmótica , Polietilenoglicóis/química , Solubilidade , Comprimidos
5.
J Control Release ; 133(1): 31-6, 2009 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-18840483

RESUMO

The mechanism of drug release from push-pull osmotic systems (PPOS) has been investigated by Magnetic Resonance Imaging (MRI) using a new benchtop apparatus. The signal intensity profiles of both PPOS layers were monitored non-invasively over time to characterize the hydration and swelling kinetics. The drug release performance was well-correlated to the hydration kinetics. The results show that (i) hydration and swelling critically depend on the tablet core composition, (ii) high osmotic pressure developed by the push layer may lead to bypassing the drug layer and incomplete drug release and (iii) the hydration of both the drug and the push layers needs to be properly balanced to efficiently deliver the drug. MRI is therefore a powerful tool to get insights on the drug delivery mechanism of push-pull osmotic systems, which enable a more efficient optimization of such formulations.


Assuntos
Preparações de Ação Retardada/química , Imageamento por Ressonância Magnética/métodos , Comprimidos/química , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacocinética , Celulose/análogos & derivados , Celulose/química , Preparações de Ação Retardada/farmacocinética , Excipientes/química , Índigo Carmim/química , Isradipino/química , Isradipino/farmacocinética , Cinética , Imageamento por Ressonância Magnética/instrumentação , Pressão Osmótica , Polietilenoglicóis/química , Cloreto de Sódio/química , Ácidos Esteáricos/química , Comprimidos/farmacocinética , Água/química
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