Engineered polymeric nanoparticles of Efavirenz: Dissolution enhancement through particle size reduction

Prolonged Release of Anti-Retroviral Efavirenz From System Using ZIF-8 as Carrier

BACKGROUND

Acquired Immunodeficiency Syndrome (AIDS) is a major public health problem in the world. One of the highly effective drugs in anti-HIV therapy is efavirenz (EFZ), which is classified as Class II according to the Classification System of Biopharmaceuticals, presenting low solubility and high permeability, this being an obstacle related to the drug.

OBJECTIVE

This study aimed to obtain an innovative system based on EFZ and the Zeolitic Imidazolate Framework (ZIF-8) to use in the development of prolonged-release pharmaceutical forms that can circumvent this problem.

METHODS

The EFZ: ZIF-8 system was obtained by a selected ex-situ method due to its higher incorporation efficiency. Different characterization techniques corroborated the obtainment of the system, and drug release was analyzed by dissolution testing under sink conditions, the profiles being adjusted to some kinetic models.

RESULTS

At pH 1.2, the structure of ZIF-8 breaks down rapidly, releasing a large amount of drug within either 3h or short time. In the pH 4.5 and 6.8 medium, the EFZ release from the EFZ: ZIF-8 system obtained in ethanol was prolonged, releasing 95% of the drug in 24h at pH 4.5 and 75% medium at pH 6.8.

CONCLUSION

It is evident that a promising pH-sensitive system was obtained using ZIF-8 as a novel carrier of EFZ intended for the alternative treatment of AIDS.

Co-stabilization of pioglitazone HCL nanoparticles prepared by planetary ball milling: in-vitro and in-vivo evaluation

Pioglitazone (PGZ) is an oral antidiabetic agent that increases cell resistance to insulin, thereby decreasing blood glucose levels. PGZ is a class II drug. Because of its pH-dependent solubility, it precipitates at the intestinal pH, resulting in an erratic and incomplete absorption following oral administration, which causes fluctuations in its plasma concentration. A nanoparticle drug delivery system offers a solution to enhance the dissolution rate of this poorly water-soluble drug. PGZ nanoparticles were formulated by the wet milling technique using a planetary ball mill. The effects of the steric stabilizer (Pluronic F-127, PL F-127), electrostatic stabilizer (sodium deoxycholate, SDC), and number of milling cycles were optimized using a Box-Behnken factorial design. The results showed that the ratio of PL F-127: SDC significantly affected the zeta potential and the dissolution efficiency (DE%) of PGZ. The optimized PGZ nanoparticle formulation enhanced the dissolution to reach 100% after 5 min. The in-vivo results showed significant enhancement in C_max (1.3-fold) compared to that of the raw powder, and both AUC_0-24 and AUC_0-∞ were significantly (p < 0.05) enhanced. In conclusion, PGZ nanoparticle formulation had enhanced dissolution rate in the alkaline media, which improved its drug bioavailability relative to that of the untreated drug.

How tenofovir disoproxil fumarate can impact on solubility and dissolution rate of efavirenz?

Efavirenz (EFZ) and tenofovir disoproxil fumarate (TDF) can be used simultaneously in the treatment of human immunodeficiency virus type1 infection. In this work the impact of TDF, a hydrophilic drug, on the solubility and dissolution rate of EFZ, a poorly water-soluble drug, was evaluated. EFZ/TDF binary mixtures in different molar ratios were prepared. Differential scanning calorimetry (DSC) results indicate the formation of a eutectic mixture, the molar ratio of 65/35 being the eutectic point. It was observed an increase in the EFZ solubility in water and acidic conditions (0.1 N HCl and biorelevant medium), in the presence of TDF. On the other hand, there was a decreasing on EFZ solubility in phosphate buffer pH 6.8, probably influenced by the lower solubility of TDF in this medium. The high solubility of TDF in water and acidic medium may have contributed to improve the solubility of EFZ, as well as the formation of a eutectic mixture, supported by X-ray powder diffraction (XRPD) and Fourier Transform infrared spectroscopy (FTIR) analyses. However, TDF solubility and dissolution rate was not significantly influenced by the presence of EFZ.

Reverse Transcriptase Inhibitors Nanosystems Designed for Drug Stability and Controlled Delivery

An in-depth analysis of nanotechnology applications for the improvement of solubility, distribution, bioavailability and stability of reverse transcriptase inhibitors is reported. Current clinically used nucleoside and non-nucleoside agents, included in combination therapies, were examined in the present survey, as drugs belonging to these classes are the major component of highly active antiretroviral treatments. The inclusion of such agents into supramolecular vesicular systems, such as liposomes, niosomes and lipid solid NPs, overcomes several drawbacks related to the action of these drugs, including drug instability and unfavorable pharmacokinetics. Overall results reported in the literature show that the performances of these drugs could be significantly improved by inclusion into nanosystems.