Publications

The aim of this study was to investigate the efficiency of hydrophilic polymers to enhance the dissolution rate of poorly water-soluble active pharmaceutical ingredients (APIs) processed by hot-melt extrusion (HME). Indomethacin (INM) and famotidine (FMT) were selected as model active substances while polyvinyl caprolactam graft copolymer, soluplus (SOL) and vinylpyrrolidone-vinyl acetate copolymer grades, Kollidon VA64 (VA64) and Plasdone S630 (S630) were used as hydrophilic polymeric carriers. For the purpose of the study, drug-polymer binary blends at various ratios were processed by a Randcastle single screw extruder. The physicochemical properties and the morphology of the extrudates were evaluated through X-ray diffraction (XRD), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Increased drug loadings of up to 40% were achieved in the extruded formulations for both drugs. INM and FMT exhibited strong plasticization effects with increasing concentrations and were found to be molecularly dispersed within the polymer blends. The in vitro dissolution studies showed increased INM/FMT release rates for all formulations compared to that of pure APIs alone.

The aim of this work was to develop sustained release solid lipid matrices of diclofenac sodium (Df-Na) processed by hot melt extrusion (HME) and subsequent compression into tablets. Different extrusion processing approaches such as "cold", "hot" and pre-mixed formulations were used to develop the Compritol(®) 888 ATO lipid matrices by altering the extrusion temperatures, drug loading and formulation composition. The extrudates were characterized via a range of techniques such as differential scanning calorimetry (DSC), hot stage microscopy (HSM) and X-ray powder diffraction (XRPD) to identify the drug state within the lipid matrix. Df-Na was found to be either in crystalline or amorphous state depending on the processing conditions. Energy dispersive X-ray (EDX) microanalysis demonstrated excellent drug distribution of Df-Na on the surface of the compressed tablets. The lipid matrices developed by HME provided sustained release of pre-mixed formulations for 12h mainly controlled by diffusion.

Over the last three decades industrial adaptability has allowed hot-melt extrusion (HME) to gain wide acceptance and has already established its place in the broad spectrum of manufacturing operations and pharmaceutical research developments. HME has already been demonstrated as a robust, novel technique to make solid dispersions in order to provide time controlled, modified, extended, and targeted drug delivery resulting in improved bioavailability as well as taste masking of bitter active pharmaceutical ingredients (APIs). This paper reviews the innumerable benefits of HME, based on a holistic perspective of the equipment, processing technologies to the materials, novel formulation design and developments, and its varied applications in oral drug delivery systems.

The purpose of this study was the in vitro and in vivo evaluation of the masking efficiency of hot melt extruded paracetamol (PMOL) formulations. Extruded granules containing high PMOL loadings in Eudragit EPO (EPO) or Kollidon VA64 (VA64) were prepared by hot-melt extrusion (HME). The taste masking effect of the processed formulation was evaluated in vivo by a panel of six healthy human volunteers. In addition, in vitro evaluation was carried out by an Astree e-tongue equipped with seven sensors. Taste sensing technology demonstrated taste improvement for both polymers by correlating the data obtained for the placebo polymers and the pure APIs alone. The best masking effect was observed for VA64 at 30% PMOL loading. The e-tongue results were in good agreement with the in vivo evaluation. In vitro dissolution of the extruded granules showed rapid PMOL releases.

In the current study Ibuprofen was embedded in a methacrylate copolymer (Eudragit® EPO) matrix to produce solid dispersions by hot-melt extrusion (HME) processing. The obtained granules were incorporated in orally disintegrating tablets (ODTs). The tablets were developed by varying the ratio of superdisintegrants such as sodium croscarmellose and crosslinked polyvinylpyrrolidone grades while a direct compression process was used to compress the ODTs under various compaction forces to optimize tablet robustness. The properties of the compressed tablets which included porosity, hardness, friability and dissolution profiles were further evaluated and compared with Nurofen® Meltlet ODTs. The taste and sensory evaluation in human volunteers demonstrated excellence in masking the bitter active and improved tablet palatability.