title: Design and evaluation of an osmotic pump tablet (OPT) for prednisolone, a poorly water soluble drug, using (SBE)7m-beta-CD.
abstract: OBJECTIVE
  The purpose of this study was to develop a controlled-porosity osmotic pump tablet (OPT) for poorly water soluble drugs using a sulfobutyl ether-beta-cyclodextrin, (SBE)7m-beta-CD or Captisol, which acted as both a solubilizer and as an osmotic agent.
  
  
  METHODS
  Prednisolone (PDL) was chosen as a model drug for this study. The release of PDL from osmotic pump devices and tablets was studied. In vivo absorption of PDL from OPT was evaluated in male beagle dogs.
  
  
  RESULTS
  PDL release from the osmotic pump tablet with (SBE)7m-beta-CD was complete. Another cyclodextrin, hydroxypropyl-beta-cyclodextrin (HP-beta-CD), and a sugar mixture of lactose and fructose resulted in incomplete release. Although PDL release from the OPT with (SBE)7m-beta-CD and the sugar formulation displayed mainly zero-order release characteristics, the tablet utilizing HP-beta-CD showed apparent first-order release characteristics. An in vivo absorption study in dogs correlated very well with the in vitro release profiles using the Japanese Pharmacopoeia dissolution method.
  
  
  CONCLUSIONS
  The present results confirm that (SBE)7m-gamma-CD can serve as both the solubilizer and the osmotic agent for OPT of PDL, and modify the input rate of PDL without compromising oral bioavailability.
authors.affiliation: Technological Development Laboratories, Fujisawa Pharmaceutical Co., Ltd., Osaka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Okimoto
authors.forename: M
authors.initials: M
authors.lastname: Miyake
authors.forename: N
authors.initials: N
authors.lastname: Ohnishi
authors.forename: R A
authors.initials: RA
authors.lastname: Rajewski
authors.forename: V J
authors.initials: VJ
authors.lastname: Stella
authors.forename: T
authors.initials: T
authors.lastname: Irie
authors.forename: K
authors.initials: K
authors.lastname: Uekama
mesh_terms: D000042:Absorption; D000818:Animals; D003505:Cyclodextrins / Q000008:administration & dosage*; D004285:Dogs; D008297:Male; D011239:Prednisolone / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D012995:Solubility; D013607:Tablets; D047392:beta-Cyclodextrins
chemical_list: D003505:Cyclodextrins; C103513:SBE7-beta-cyclodextrin; D013607:Tablets; D047392:beta-Cyclodextrins; D011239:Prednisolone