Stability-enhanced hot-melt extruded amorphous solid dispersions via combinations of Soluplus® and HPMCAS-HF

AAPS PharmSciTech. 2015 Aug;16(4):824-34. doi: 10.1208/s12249-014-0269-6. Epub 2015 Jan 8.

Abstract

The aim of this study was to evaluate a novel combination of Soluplus® and hypromellose acetate succinate (HPMCAS-HF) polymers for solubility enhancement as well as enhanced physicochemical stability of the produced amorphous solid dispersions. This was accomplished by converting the poorly water-soluble crystalline form of carbamazepine into a more soluble amorphous form within the polymeric blends. Carbamazepine (CBZ), a Biopharmaceutics Classification System class II active pharmaceutical ingredient (API) with multiple polymorphs, was utilized as a model drug. Hot-melt extrusion (HME) processing was used to prepare solid dispersions utilizing blends of polymers. Drug loading showed a significant effect on the dissolution rate of CBZ in all of the tested ratios of Soluplus® and HPMCAS-HF. CBZ was completely miscible in the polymeric blends of Soluplus® and HPMCAS-HF up to 40% drug loading. The extrudates were characterized by differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and dissolution studies. DSC and XRD data confirmed the formation of amorphous solid dispersions of CBZ in the polymeric blends of Soluplus® and HPMCAS-HF. Drug loading and release of CBZ was increased with Soluplus® (when used as the primary matrix polymer) when formulations contained Soluplus® with 7-21% (w/w) HPMCAS-HF. In addition, this blend of polymers was found to be physically and chemically stable at 40°C, 75% RH over 12 months without any dissolution rate changes.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Calorimetry, Differential Scanning
  • Carbamazepine / chemistry
  • Chromatography, High Pressure Liquid
  • Hot Temperature
  • Methylcellulose / analogs & derivatives*
  • Methylcellulose / chemistry
  • Polyethylene Glycols / chemistry*
  • Polyvinyls / chemistry*
  • Solubility
  • Spectroscopy, Fourier Transform Infrared
  • Thermogravimetry
  • X-Ray Diffraction

Substances

  • Polyvinyls
  • polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer
  • Carbamazepine
  • Polyethylene Glycols
  • hydroxypropylmethylcellulose acetate succinate
  • Methylcellulose