28 research outputs found

    Antifungal and Antiparasitic Drug Delivery

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    Fungal and parasitic diseases affect more than a billion people across the globe, one-sixth of the world’s population, mostly located in developing countries. The lack of effective and safer treatments combined with a deficient diagnosis lead to serious chronic illness or even death. There is a mismatch between the rate of drug resistance and the development of new medicines. Formulation of antifungal and antiparasitic drugs adapted to different administration routes is challenging, bearing in mind their poor water solubility, which limits their bioavailability and efficacy. Hence, there is an unmet clinical need to develop vaccines and novel formulations and drug delivery strategies that can improve the bioavailability and therapeutic effect by enhancing their dissolution, increasing their chemical potency, stabilising the drug and targeting high concentration of drug to the infection sites. This Editorial regards the ten research contributions presented in the Special Issue “Antifungal and Antiparasitic Drug Delivery”

    One and Two-Step In Vitro-In Vivo Correlations Based on USP IV Dynamic Dissolution Applied to Four Sodium Montelukast Products

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    Montelukast is a weak acid drug characterized by its low solubility in the range of pH 1.2 to 4.5, which may lead to dissolution-limited absorption. The aim of this paper is to develop an in vivo predictive dissolution method for montelukast and to check its performance by establishing a level-A in vitro-in vivo correlation (IVIVC). During the development of a generic film-coated tablet formulation, two clinical trials were done with three different experimental formulations to achieve a similar formulation to the reference one. A dissolution test procedure with a flow-through cell (USP IV) was used to predict the in vivo absorption behavior. The method proposed is based on a flow rate of 5 mL/min and changes of pH mediums from 1.2 to 4.5 and then to 6.8 with standard pharmacopoeia buffers. In order to improve the dissolution of montelukast, sodium dodecyl sulfate was added to the 4.5 and 6.8 pH mediums. Dissolution profiles in from the new method were used to develop a level-A IVIVC. One-step level-A IVIVC was developed from dissolution profiles and fractions absorbed obtained by the Loo–Riegelman method. Time scaling with Levy’s plot was necessary to achieve a linear IVIVC. One-step differential equation-based IVIVC was also developed with a time-scaling function. The developed method showed similar results to a previously proposed biopredictive method for montelukast, and the added value showed the ability to discriminate among different release rates in vitro, matching the in vivo clinical bioequivalence results

    Targeting lung macrophages for fungal and parasitic pulmonary infections with innovative amphotericin B dry powder inhalers

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    The incidence of fungal pulmonary infections is known to be on the increase, and yet there is an alarming gap in terms of marketed antifungal therapies that are available for pulmonary administration. Amphotericin B (AmB) is a highly efficient broad-spectrum antifungal only marketed as an intravenous formulation. Based on the lack of effective antifungal and antiparasitic pulmonary treatments, the aim of this study was to develop a carbohydrate-based AmB dry powder inhaler (DPI) formulation, prepared by spray drying. Amorphous AmB microparticles were developed by combining 39.7% AmB with 39.7% γ-cyclodextrin, 8.1% mannose and 12.5% leucine. An increase in the mannose concentration from 8.1 to 29.8%, led to partial drug crystallisation. Both formulations showed good in vitro lung deposition characteristics (80% FPF< 5 µm and MMAD < 3 µm) at different air flow rates (60 and 30 L/min) when used with a DPI, but also during nebulisation upon reconstitution in water

    Composición química IGF para el tratamiento y prevención de enfermedades neurodegenerativas

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    Traducción de Patente Europea E03744388 (fecha de solicitud, 21/02/2003).-- Prioridad: ES20020228200200491.-- Titulares: Consejo Superior de Investigaciones Científicas (CSIC), Universidad Complutense de Madrid (UCM).La invención se refiere a nuevas composiciones terapéuticas de administración lenta de IGF-I, a un procedimiento de preparación y obtención de las mismas y a su empleo para la elaboración de medicamentos para el tratamiento y prevención de enfermedades neurodegenerativas como, entre otras, la enfermedad de Alzheimer o la ataxia cerebelar.Estas composiciones se corresponden con microesferas de tamaño menor de 5 micrometros, entre otras características, y con cápsulas de implantación subcutánea.Peer reviewe

    Enhanced bioavailability and anthelmintic efficacy of mebendazole in redispersible microparticles with low-substituted hydroxypropylcellulose

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    Antecedentes: el mebendazol (MBZ) es un fármaco extremadamente insoluble y, por lo tanto, poco absorbido y los resultados clínicos variables pueden correlacionarse con las concentraciones sanguíneas. La necesidad de un tratamiento prolongado con dosis altas de este fármaco aumenta el riesgo de efectos adversos. Métodos: En el presente estudio preparamos micropartículas redispersables (RDM) que contienen MBZ, un fármaco oral poco soluble en agua, en diferentes proporciones de hidroxipropilcelulosa poco sustituida (L-HPC). Investigamos las estructuras de micropartículas que emergen espontáneamente tras la dispersión de un RDM en medio acuoso y dilucidamos su influencia en la disolución, y también en su biodisponibilidad oral y eficiencia terapéutica utilizando un modelo murino de infección con el parásito nematodo Trichinella espiralis. Resultados: Se obtuvieron porcentajes elevados de fármaco disuelto con RDM en proporciones 1:2,5 y 1:5 de MBZ:L-HPC. El análisis térmico mostró una amorfización de MBZ en el RDM por la ausencia de un pico de fusión claro de MBZ en las formulaciones. El rápido comportamiento de disolución podría deberse a la disminución de la cristalinidad del fármaco, el rápido tiempo de disolución de portadores como L-HPC, junto con su superior dispersabilidad y excelentes propiedades humectantes. RDM-1:2,5 y RDM-1:5 dieron como resultado un aumento de la concentración plasmática máxima y de los valores de área(s) bajo la curva (AUC)(0-infinito). Asimismo, después de la administración oral de RDM-1:2,5 y RDM-1:5, el AUC(0-infinito) fue 2,67 y 2,97 veces mayor, respectivamente, en comparación con el MBZ puro. La actividad terapéutica, evaluada en el ciclo de vida de Trichinella espiralis, mostró que RDM-1:5 fue el más eficaz para reducir el número de parásitos (4,56 veces) en comparación con el MBZ puro, en estado enquistado. Conclusión: El MBZ: L-HPC RDM podría ser una forma efectiva de mejorar la biodisponibilidad oral y la actividad terapéutica utilizando dosis bajas de MBZ (5 mg/kg), lo que implica un bajo grado de toxicidad para los humanos.Background: Mebendazole (MBZ) is an extremely insoluble and therefore poorly absorbed drug and the variable clinical results may correlate with blood concentrations. The necessity of a prolonged high dose treatment of this drug increases the risk of adverse effects. Methods: In the present study we prepared redispersible microparticles (RDM) containing MBZ, an oral, poorly water-soluble drug, in different proportions of low-substituted hydroxypropylcellulose (L-HPC). We investigated the microparticulate structures that emerge spontaneously upon dispersion of an RDM in aqueous medium and elucidated their influence on dissolution, and also on their oral bioavailability and therapeutic efficiency using a murine model of infection with the nematode parasite Trichinella spiralis. Results: Elevated percentages of dissolved drug were obtained with RDM at 1:2.5 and 1:5 ratios of MBZ: L-HPC. Thermal analysis showed an amorphization of MBZ in the RDM by the absence of a clear MBZ melting peak in formulations. The rapid dissolution behavior could be due to the decreased drug crystallinity, the fast dissolution time of carriers as L-HPC, together with its superior dispersibility and excellent wetting properties. RDM-1:2.5 and RDM-1:5 resulted in increased maximum plasma concentration and area(s) under the curve (AUC)0-∞ values. Likewise, after oral administration of the RDM-1:2.5 and RDM-1:5 the AUC0-∞ were 2.67- and 2.97-fold higher, respectively, compared to those of pure MBZ. Therapeutic activity, assessed on the Trichinella spiralis life cycle, showed that RDM-1:5 was the most effective in reducing the number of parasites (4.56-fold) as compared to pure MBZ, on the encysted stage. Conclusion: The MBZ: L-HPC RDM might be an effective way of improving oral bioavailability and therapeutic activity using low doses of MBZ (5 mg/kg), which implies a low degree of toxicity for humans.Universidad Complutense de MadridDepto. de Farmacia Galénica y Tecnología AlimentariaFac. de FarmaciaTRUEpu

    Efficacy and toxicity evaluation of new amphotericin B micelle systems for brain fungal infections.

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    The aim of this work is to study the micelle systems of amphotericin B (AmB) and surfactant sodium deoxycholate (NaDC) as possible formulations to treat brain fungal infections. Fungizone(®) and Ambisome(®) were used as AmB references. The particle size, aggregation state, toxicity and efficacy of AmB:NaDC micelles were studied with increasing proportions of NaDC. Differences in the size and aggregation state of the reference formulations and micellar NaDC formulations might explain the differences in their distribution and therefore in their toxicity and efficacy. AmB:NaDC 1:0.8 and 1:1.5 nano-sized micelle systems showed a poly-aggregated form of AmB and small mean particle size (450-750 nm). The AmB:NaDC 1:0.8 and AmB:NaDC 1:1.5 micelle systems studied showed an 8-fold lower toxicity than Fungizone(®). Efficacy was examined in a murine candidiasis model by determining the survival rate and tissue burden reduction in kidneys and brain. The AmB:NaDC 1:1.5 micellar system at 5mg/kg of AmB and the highest amount of NaDC (7.5 mg/kg) presented a good survival rate, and induced a major clearance of brain infection. The new AmB:NaDC 1:1.5 nano-sized micelle system is a promising formulation with a good efficacy/toxicity ratio, which can be attributed to its particle size, AmB aggregation state and NaDC content
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