Preparation and evaluation of solid dispersions of a new antitumor compound based on early-stage preparation discovery concept

AAPS PharmSciTech. 2013 Jun;14(2):629-38. doi: 10.1208/s12249-013-9948-y. Epub 2013 Apr 30.

Abstract

Ensuring sufficient drug solubility is a crucial problem in pharmaceutical-related research. For water-insoluble drugs, various formulation approaches are employed to enhance the solubility and bioavailability of lead compounds. The goal of this study was to enhance the dissolution and absorption of a new antitumor lead compound, T-OA. Early-stage preparation discovery concept was employed in this study. Based on this concept, a solid dispersion system was chosen as the method of improving drug solubility and bioavailability. Solid dispersions of T-OA in polyvinylpyrrolidone (PVP) K30 were prepared by the solvent evaporation method. Dissolution testing determined that the ideal drug-to-PVP ratio was 1:5. X-ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry were employed to confirm the formation of solid dispersions. Scanning electron microscopy demonstrated that T-OA was converted into an amorphous form. Both in vitro dissolution testing and the in vivo studies demonstrated that the solubility and bioavailability of T-OA were significantly improved when formulated in a solid dispersion with PVP. The dissolution rate of the T-OA/PVP solid dispersion was greatly enhanced relative to the pure drug, and the relative bioavailability of T-OA solid dispersions was found to be 392.0%, which is 4-fold higher than the pure drug.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Animals
  • Antineoplastic Agents, Phytogenic / administration & dosage
  • Antineoplastic Agents, Phytogenic / chemistry*
  • Antineoplastic Agents, Phytogenic / pharmacokinetics
  • Biological Availability
  • Calorimetry, Differential Scanning
  • Chemistry, Pharmaceutical
  • Drug Carriers
  • Drug Discovery* / methods
  • Male
  • Microscopy, Electron, Scanning
  • Oleanolic Acid / administration & dosage
  • Oleanolic Acid / analogs & derivatives
  • Oleanolic Acid / chemistry*
  • Oleanolic Acid / pharmacokinetics
  • Povidone / chemistry
  • Pyrazines / administration & dosage
  • Pyrazines / chemistry*
  • Pyrazines / pharmacokinetics
  • Rats
  • Rats, Sprague-Dawley
  • Solubility
  • Spectroscopy, Fourier Transform Infrared
  • Technology, Pharmaceutical / methods
  • X-Ray Diffraction

Substances

  • Antineoplastic Agents, Phytogenic
  • Drug Carriers
  • Pyrazines
  • Oleanolic Acid
  • Povidone