Solubility and dissolution performances of spray-dried solid dispersion of Efavirenz in Soluplus.

Efavirenz (EFV), a first-line anti-HIV drug largely used as part of antiretroviral therapies, is practically insoluble in water and belongs to BCS class II (low solubility/high permeability). The aim of this study was to improve the solubility and dissolution performances of EFV by formulating an amorphous solid dispersion of the drug in polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (Soluplus®) using spray-drying technique. To this purpose, spray-dried dispersions of EFV in Soluplus® at different mass ratios (1:1.25, 1:7, 1:10) were prepared and characterized using particle size measurements, SEM, XRD, DSC, FTIR and Raman microscopy mapping. Solubility and dissolution were determined in different media. Stability was studied at accelerated conditions (40 °C/75% RH) and ambient conditions for 12 months. DSC and XRD analyses confirmed the EFV amorphous state. FTIR spectroscopy analyses revealed possible drug-polymer molecular interaction. Solubility and dissolution rate of EFV was enhanced remarkably in the developed spray-dried solid dispersions, as a function of the polymer concentration. Spray-drying was concluded to be a proper technique to formulate a physically stable dispersion of amorphous EFV in Soluplus®, when protected from moisture.

Formulation, Development and Scale-Up of Fixed-Dose Combination Tablets Containing Zidovudine, Lamivudine and Nevirapine.

BACKGROUND: The development of antiretroviral associations in a single dosage form aims to ensure improved efficacy, low costs and better adherence to treatment. OBJECTIVE: This work performed the pharmacotechnical development, coating, and stability studies of fixed-dose combination tablets of zidovudine, lamivudine and nevirapine (300 + 200 + 150 mg, respectively). METHODS: Qualitative and quantitative planning of diluents (101 and 250 microcrystalline cellulose, spray-dried monohydrate lactose and corn starch) and coating polymers (Opadry white II HP® and Instacoat Aqua Moistshield II®) were analyzed, and direct compression (DC) and wet granulation (WG) methods were tested aiming the development of the pharmaceutical form. Quality control was carried out according to the specifications set by official compendia. The chosen formulation was scaled-up and the industrial batches were submitted to accelerated and long-term stability studies. RESULTS: The batches obtained by WG met the requirements, using 101 microcrystalline cellulose, corn starch and Opadry white II HP® as excipients. The DC trial was not possible due to the need of a greater ratio of excipients to improve formulation properties. CONCLUSION: Thus, this study brings a new therapeutic alternative for HIV treatment, contributing to the development of another possibility to simplify drug administration.

Amorphous solid dispersions of hecogenin acetate using different polymers for enhancement of solubility and improvement of anti-hyperalgesic effect in neuropathic pain model in mice.

Hecogenin acetate (HA) is an acetylated sapogenin that has shown potential antihyperalgesic activity, inhibiting descending pain and acting in opioid receptors. However, HA exhibits poor aqueous solubility, which may limit its application. This study aims to develop amorphous solid dispersions (ASD) using five hydrophilic polymers, to characterize them and to evaluate their antihyperalgesic activity. Physicochemical characterization was performed by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transformed Infrared (FTIR) spectroscopy. In order to evaluate the hyperalgesia of the ASD, sciatic nerve crush injury (NCI) was induced in mice followed by administration of the ASD, where three parameters were evaluated: mechanical and thermal hyperalgesia as well as grip strength. XRD and SEM showed that ASD of HA with HPMC obtained by kneading (KND) presented an amorphous profile, unlike the others polymers, indicating interaction between HA and HPMC. FTIR analysis evidenced the strong interaction between HA and HPMC. Although the results of mechanical hyperalgesia were slightly improved on the groups treated with ASD of HA with HPMC, the thermal hyperalgesia showed that the incorporation of HA into HPMC matrix significantly improved its antinociceptive activity.

Desenvolvimento e validação de método analítico para nistatina creme vaginal por cromatografia líquida de alta eficiência / Development and validation of an analytical method for nystatin vaginal cream by high performance liquid chromatography

A nistatina é um antibiótico poliênico, com características fungistáticas e fungicidas, que age desestruturando a membrana celular de fungos e leveduras. O creme vaginal de nistatina é usado para o tratamento da candidíase vaginal. Até recentemente, os compêndios oficiais preconizavam o ensaio microbiológico para doseamento deste antibiótico, método este considerado inviável na rotina de centros de controle de qualidade, devido ao tempo excessivo para liberação dos resultados. Visando obter um método alternativo para o doseamento do creme vaginal de nistatina, procurou-se desenvolver e validar um método cromatográfico (CLAE). O método desenvolvido utilizou como fase estacionária uma coluna de fase reversa, C18, 3,9 x 150 mm, 4 mm, à temperatura de 30 ºC. A fase móvel foi constituída por tampão fosfato de sódio 0,25 mM e EDTA 0,025 mM, pH 6,00, metanol e acetonitrila (40:30:30), vazão de 1,0 mL/minuto e comprimento de onda 305 nm. O método validado revelou-se exato, preciso, robusto, linear e específico, além de rápido e prático, podendo ser utilizado para o doseamento analítico de creme vaginal de nistatina.

Nystatin is a polyenic antibiotic with fungistatic and fungicide characteristics that acts by de-structuring the cellular membrane of fungi and yeast. The nystatin vaginal cream is used for the treatment of vaginal candidiasis. Until recently, the official compendia professed the microbiological trial for dosing this antibiotic, method considered as non-feasible in the routine of quality control centers due to the excessive time for release of results. Aiming at obtaining an alternative method for dosing nystatin vaginal cream, a chromatographic method (HPLC) was developed and validated. The method developed used a reversible phase column of C18, 3.9 x 150 mm, 4 mm, at 30 ºC. The mobile phase was made up of a 0.25 mM sodium phosphate buffer and 0.025 mM EDTA, pH 6.00, methanol and acetonitrile (40:30:30), rate of 1.0 mL/minute and wavelength of 305 nm. The validated method showed to be accurate, precise, robust, linear and specific, in addition to being fast and practical, able to be used for analytic dosing of nystatin vaginal cream.