Novel montelukast sodium-loaded clear oral solution prepared with hydroxypropyl-β-cyclodextrin as a solubilizer and stabilizer: enhanced stability and bioequivalence to commercial granules in rats

Enhanced Stability and Compatibility of Montelukast and Levocetirizine in a Fixed-Dose Combination Monolayer Tablet

The purpose of this study was to enhance the stability of montelukast and levocetirizine for the development of a fixed-dose combination (FDC) monolayer tablet. To evaluate the compatibility of montelukast and levocetirizine, a mixture of the two drugs was prepared, and changes in the appearance characteristics and impurity content were observed in a dry oven at 60 °C. Excipients that contributed minimally to impurity increases were selected to minimize drug interactions. Mannitol, microcrystalline cellulose, croscarmellose sodium, hypromellose, and sodium citrate were chosen as excipients, and montelukast-levocetirizine FDC monolayer tablets were prepared by wet granulating the two drugs separately. A separate granulation of montelukast and levocetirizine, along with the addition of sodium citrate as a pH stabilizer, minimized the changes in tablet appearance and impurity levels. The prepared tablets demonstrated release profiles equivalent to those of commercial products in comparative dissolution tests. Subsequent stability testing at 40 ± 2 °C and 75 ± 5% RH for 6 months confirmed that the drug content, dissolution rate, and impurity content met the specified acceptance criteria. In conclusion, the montelukast-levocetirizine FDC monolayer tablet developed in this study offers a potential alternative to commercial products.

Characterization of interactions of montelukast sodium with human serum albumin: multi-spectroscopic techniques and computer simulation studies

The interaction mechanism of montelukast sodium and HSA was characterized using spectroscopic and computer methods.

A novel WH-flags method based on reducing the acidity of molybdenum blue (MB) reaction and stabilization by EDTA for quickly detecting phosphorus in water

There are two popular methods to measure reactive phosphorus (P) and total P: the GB11893-89 method in China and the 4500-P E method of the APHA in the US. However, their drawbacks, including long reaction time and narrow linear range, cannot satisfy the demand for modern analytic techniques. Here, based on reducing the acidity of the molybdenum blue (MB) reaction, and then stabilizing with EDTA, we have developed a novel method (WH-flags) to quickly measure both reactive P and total P. In the WH-flags method, "W" stands for Wide linear ranges (0-1.4 mg L-1 for reactive P & 0-1.8 mg L-1 for total P), "H" stands for High tolerance of different matrices (it can be adapted to a wide spectrum of samples), "f" is fast reaction time (2 min), "l" is long stabilization (40 min), "a" stands for appropriate recovery rates (89.1-103.2%), "g" is good precision and accuracy (CVs < 5% & Res < 5%) and "s" is small volume of samples (5-10 mL). The WH-flags method showed good linearity (R2 > 0.999). The WH-flags method should have broad application in monitoring P from different aqueous samples in the future.

Comparison of a revaprazan-loaded solid dispersion, solid SNEDDS and inclusion compound: Physicochemical characterisation and pharmacokinetics

The aim of this research was to compare three strategies for enhancing the solubility of poorly water-soluble revaprazan hydrochloride: solid dispersion, solid SNEDDS and inclusion compound. The influence of polymers, surfactants and oils on the drug solubility was assessed, and via the chosen carriers, the three types of formulations were prepared utilising spray drying technique. Their physicochemical properties, solubility, dissolution and pharmacokinetics in rats were performed compared with revaprazan powder. Among the liquid SNEDDS formulations assessed, the compositions of revaprazan, peceol, Tween 80 and Labrasol (10:15:55:30, weight ratio) provided the smallest emulsion size. Moreover, this liquid SNEDDS and dextran were suspended/dissolved in distilled water, and spray-dried, producing an optimal revaprazan-loaded solid SNEDDS. The appropriate solid dispersion and inclusion compound were composed of revaprazan, hydroxypropylmethylcellulose and cremophor A25 (5:1.4:5.6) and drug and hydroxyl-β-cyclodextrin (2.5:8.77), respectively. The crystalline drug was converted to an amorphous state in all formulations. In the solid dispersion, the drug was attached to the hydrophilic carrier. The solid SNEDDS and inclusion compound contained aggregate microspheres and separate microspheres, respectively. All formulations significantly increased the drug solubility, dissolution, plasma concentration and AUC compared with revaprazan powder. These properties were ranked in the order solid dispersion ≥ solid SNEDDS > inclusion compound. Particularly, the solid dispersion improved about 9500-fold drug solubility and 10-fold oral bioavailability. Thus, the improved properties were considerably dependent upon these techniques, although all of the techniques employed similar mechanisms. Among the strategies checked, the solid dispersion system would be recommended as an oral revaprazan-loaded pharmaceutical product.

Effect of HM30181 mesylate salt-loaded microcapsules on the oral absorption of paclitaxel as a novel P-glycoprotein inhibitor

The purpose of this study was to develop HM30181 mesylate salt (HM30181M)-loaded microcapsules as a novel P-glycoprotein inhibitor for enhancing the oral absorption of paclitaxel. The effect of various carriers including hydrophilic polymers and solvents on the solubility of HM30181M were evaluated. Among the hydrophilic polymers and solvents tested, HPMC and methylene chloride (and ethanol) provided the highest HM30181M solubility. Numerous HM30181M-loaded microcapsules were prepared with HPMC, silicon dioxide and acidifying agents using a spray-drying technique, and their solubility, dissolution and physicochemical properties were evaluated. Furthermore, a pharmacokinetic study was performed after oral administration of paclitaxel alone, simultaneously with HM30181M powder or HM30181M-loaded microcapsules to rats. Among the acidifying agents investigated, phosphoric acid provided the best improvement in the solubility and dissolution of HM30181M. Moreover, the microcapsule composed of HM30181M, HPMC, silicon dioxide and phosphoric acid at a weight ratio of 3:6:3:2 remarkably enhanced the solubility and dissolution of HM30181M compared with the HM30181M powder alone. The microcapsules were spherical in shape, had a reduced particle size of about 7μm, and contained HM30181M in an amorphous state. Furthermore, this microcapsule significantly enhanced HM30181M absorption, making it about 1.7-fold faster and 1.6-fold greater after simultaneous administration, leading to about 70- and 2-fold improved oral bioavailability of paclitaxel compared with paclitaxel alone and the simultaneous administration with HM30181M powder, respectively. Thus, this novel microcapsule could be a potential candidate for effective P-glycoprotein inhibition during oral administration of paclitaxel.

Montelukast medicines of today and tomorrow: from molecular pharmaceutics to technological formulations

Montelukast sodium is a leukotriene antagonist of growing interest as an alternative therapy for asthma across different age groups due to its bronchoprotective, anti-inflammatory and anti-allergic properties. Currently, montelukast is commercialized only in oral solid dosage forms, which are the favorite of adult patients but may pose challenges in administration to children of young age or patients suffering from dysphagia. This review presents a comprehensive revision of scientific reports and patents on emerging strategies for the delivery of montelukast. A common ground to these reports is the pursue of an enhanced montelukast performance, by increasing its bioavailability and physico-chemical stability. A wide variety of strategies can be found, from the formation of supramolecular adducts with cyclodextrins to encapsulation in nanoparticles and liposomes. The new dosage forms for montelukast are designed for non-enteric absorption, some for absorption in the oral cavity and another two being for local action in the nasal mucosa or in the pulmonary epithelium. The review describes the emerging delivery strategies to circumvent the current limitations to the use of montelukast that are expected to ultimately lead to the development of more patient-compliant dosage forms.

Novel montelukast sodium-loaded stable oral suspension bioequivalent to the commercial granules in rats

To develop a montelukast sodium-loaded stable oral suspension bioequivalent to the commercial granules in rats, several montelukast sodium-loaded suspensions were prepared with a suspending agent, stabilizers and anti-aggregation agents, and their stabilities were investigated by visually observing the sedimentation phenomenon and determining the concentration of the degradation product. Moreover, dissolution and pharmacokinetic studies of the optimized formulation were examined in rats compared to commercial montelukast sodium-loaded granules. Avicel RC-591 (Avicel), a suspending agent, prevented the sedimentation of these suspensions at >2.496 (w/v) per cent composition. Amongst the stabilizers tested, fumaric acid provided the lowest concentration of montelukast sulphoxide (a degradation product) in these suspensions at 40 °C, demonstrating its excellent stabilizing activity. Furthermore, as an anti-aggregation agent, glycerin gave lower amounts of degradation product than those with poloxamer 407 and Tween 80. In particular, montelukast-loaded oral suspension, an aqueous suspension containing montelukast sodium/Avicel/fumaric acid/glycerin at a concentration of 312/2496/15.6/62.4 (mg/100 ml), and the commercial granules exhibited similar dissolution profiles in 0.5% (w/v) aqueous solution of sodium lauryl sulphate. Moreover, the pharmacokinetics in rats provided by this suspension was comparable to that of the commercial granules, suggesting that they were bioequivalent. In addition, it was physically and chemically stable at 40 °C for at least 6 months. Thus, this montelukast sodium-loaded oral suspension, with bioequivalence to the commercial granules and excellent stability, could be a prospective dosage form for the treatment of asthma.