Comparative evaluation of the hepatotoxicity, phototoxicity and photosensitizing potential of dronedarone hydrochloride and its cyclodextrin-based inclusion complexes.

In this study, the hepatotoxicity, phototoxicity and photosensitizing potential of free dronedarone (DRO) and its inclusion complexes with ß-cyclodextrin (ß-CD) and 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD), prepared by different methods, were investigated by using in vitro cell-based approaches. The results of the 3T3 NRU phototoxicity assay showed that free DRO and the CD-based inclusion complexes did not present any substantial phototoxic potential. The photosensitizing potential was assessed by using THP-1 cells and IL-8 as a biomarker, and the experimental data confirmed that both the free drug and the inclusion complexes are likely to cause skin photosensitization, as they were able to induce IL-8 release after irradiation. Nevertheless, the inclusion complexes obtained by kneading followed by spray-drying induced a lower IL-8 release and also presented a smaller stimulation index in comparison with free DRO, suggesting a reduction in the photosensitizing potential. Finally, the free drug and inclusion complexes were also tested for hepatotoxicity using HepG2 cells. Even though lower IC50 values were found for the inclusion complexes prepared by kneading followed by spray-drying, there was no significant difference, indicating that the complexation of dronedarone did not induce hepatotoxicity. Overall, the obtained data confirmed that the inclusion complexes prepared by kneading followed by spray-drying, especially those based on HP-ß-CD, appeared to be the most promising formulations and, therefore, could be encouragingly explored in the development of novel pharmaceutical dosage forms containing DRO, presumably with reduced side effects and improved safety profile.

Preparation, characterization and in vitro cytotoxicity study of dronedarone hydrochloride inclusion complexes.

Dronedarone is a new antiarrhythmic drug for the treatment of atrial fibrillation. This study investigated the complexation of dronedarone hydrochloride with ß­cyclodextrin (ß-CD) and 2­hydroxypropil­ß­CD (HP-ß-CD) using three different techniques. The complexes in the solid state were characterized by DSC, TGA, PXRD, FT-IR, SEM and 1H NMR, demonstrating the formation of the inclusion complexes and exhibiting different properties from the pure drug. Its aqueous solubility increased about 4.0-fold upon complexation with ß-CD and HP-ß-CD. The dissolution rate of the drug was notably improved in all tested physiological pH values from 1.2 to 6.8 in the presence of both cyclodextrins. Furthermore, an in vitro cytotoxic assay revealed that the inclusion complexes could reduce the cytotoxic effects of the drug on 3T3 cells. The overall results suggest that the inclusion complexes with ß-CD and HP-ß-CD may be potentially useful in the preparation of novel pharmaceutical formulations containing dronedarone hydrochloride.

Stability indicating RP-LC-PDA method for the quantitative analysis of saxagliptin in pharmaceutical dosage form / Estabilidade indicando o método de RP-LC-PDA para a análise quantitativa de saxagliptina em forma de dosagem farmacêutica

Saxagliptin is a potent and selective inhibitor of the enzyme dipeptidyl peptidase 4. It is effective in the treatment of type 2 diabetes mellitus because it stimulates the pancreas to produce insulin. In the present study, a liquid chromatography method was developed and validated to quantify the drug in tablets. This method was based on the isocratic elution of saxagliptin, using a mobile phase consisting of 0.1% phosphoric acid at pH 3.0 - methanol (70: 30, v/v) at a flow rate of 1 mL.min^-1 with UV detection at 225 nm. The chromatographic separation was achieved in 8 minutes on a Waters XBridge C18 column (250 mm x 4.6 mm, 5µm) maintained at ambient temperature. The proposed method proved to be specific and robust for the quality control of saxagliptin in pharmaceutical dosage forms, showing good linearity in the range of 15.0 - 100.0 µg.mL^-1 (r>0.999), precision (RSD<1.49%) and accuracy values between 99.42 and 101.59%. The method was found to be stability indicating and was successfully applied for the analysis of saxagliptin in tablets in a routine quality control laboratory...

A saxagliptina é uma inibidora potente e seletiva da enzima dipeptidil peptidase 4. É efetiva no tratamento do Diabete mellitus tipo 2, pois estimula a produção de insulina pelo pâncreas. No presente estudo, desenvolveu-se e validou-se método por cromatografia líquida de alta eficiência para quantificar o fármaco em comprimidos. O método foi baseado em eluição isocrática, utilizando fase móvel constituída por ácido fosfórico 0,1% pH 3,0-metanol (70 : 30, v/v), fluxo de 1,0 mL.min^-1, com detecção UV em 225 nm. A separação cromatográfica foi alcançada em 8 minutos em coluna Waters XBridge C18 (250 mm x 4,6 mm, 5 µm) mantida à temperatura ambiente. O método proposto mostrou-se específico e robusto para o controle de qualidade de saxagliptina em comprimidos, sendo linear na faixa de concentração de 15,0-100,0 µg.mL^-1 (r>0,999), preciso (RSD<1,49%) e exato, com resultados entre 99,42 e 101,59%. O método mostrou-se indicativo de estabilidade e foi aplicado com sucesso no controle de qualidade de saxagliptina em comprimidos...