Controlled and complete release of a model poorly water-soluble drug, prednisolone, from hydroxypropyl methylcellulose matrix tablets using (SBE)7m-β-cyclodextrin as a solubilizing agent

✍ Scribed by Venkatramana M. Rao; John L. Haslam; Valentino J. Stella

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 244 KB
• Volume: 90
• Category: Article
• ISSN: 0022-3549
• DOI: 10.1002/jps.1034

✦ Synopsis

Sustained-release formulations such as hydroxypropyl methylcellulose (HPMC)based hydrophilic matrix tablets of poorly water-soluble drugs often result in incomplete release because of the poor solubility and dissolution rate of the drug in the hydrophilic matrix. Sulfobutylether-b-cyclodextrins ((SBE) 7M -b-CDs) have been known to improve the solubility of such drugs by forming inclusion complexes. The present paper deals with the modi®cation of drug release from an HPMC-based matrix tablet of a sparingly water-soluble drug, prednisolone (PDL), using (SBE) 7M -b-CD as a solubilizing agent. Tablets were prepared by direct compression of a physically mixed PDL, (SBE) 7M -b-CD, and polymer. On exposure to water, an in situ PDL:(SBE) 7Mb-CD complex was formed in the gel layer, and enhanced drug release relative to a control formulation was observed (lactose used as the excipient instead of (SBE) 7M -b-CD ). Other possible changes due to the incorporation of (SBE) 7M -b-CD in the formulation were also probed. Incorporation of (SBE) 7M -b-CD lead to a higher water uptake relative to the control (lactose) formulation. For a ®xed total tablet weight, polymer type, and loading, the drug release rate appeared to depend on the molar ratio of (SBE) 7M -b-CD to PDL and not the absolute amount of (SBE) 7M -b-CD present in the matrix tablet. This work shows that incorporation of (SBE) 7M -b-CD into the matrix tablets could be considered in designing a sustained-release tablet of poorly watersoluble drugs.