title: Formulation and evaluation of thienorphine hydrochloride sublingual delivery system.
abstract: Thienorphine hydrochloride (ThH) is a highly insoluble and readily metabolized partial-opioid agonist. It is used for the treatment of pain and heroin addiction. This study aimed to formulate and evaluate sublingual delivery systems containing ThH. Dimethyl-β-cyclodextrin (DM-β-CD) can enhance the solubility and permeability of hydrophobic drugs. In this paper, ThH cyclodextrin inclusion complexes were prepared and administrated sublingually with the objective of improving the drug's aqueous solubility, in vitro permeation rate, and in vivo absorption rate. The formulation was prepared with DM-β-CD using the freeze-dried method and characterized using phase solubility, differential scanning calorimetry (DSC), X-ray and NMR analyses. The results of each test indicated the formation of dynamic inclusion complexes between ThH and DM-β-CD. The inclusion complexes also showed significant increases in in vitro aqueous solubility and mucosal permeability. According to the pharmacokinetic study of the complex in rats, the AUC and C(max) values of the sublingual delivery group were 40 and 46 times higher than those of the gastrointestinal group, whereas t(max) was shorter, which proved that in vivo absorption and metabolism had been improved. It can therefore be concluded that the inclusion technology and sublingual delivery system were suitable for ThH development.
authors.affiliation: Beijing Institute of Pharmacology and Toxicology, No. 27 Taiping Road, Beijing 100850, PR China.
authors.forename: Fei
authors.initials: F
authors.lastname: Liu
authors.forename: Yumei
authors.initials: Y
authors.lastname: Zhao
authors.forename: Jianxu
authors.initials: J
authors.lastname: Sun
authors.forename: Yongliang
authors.initials: Y
authors.lastname: Gao
authors.forename: Zhenqing
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000286:Administration, Sublingual; D000818:Animals; D002047:Buprenorphine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry / Q000493:pharmacokinetics; D002152:Calorimetry, Differential Scanning; D016503:Drug Delivery Systems; D007413:Intestinal Mucosa / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D010539:Permeability; D051381:Rats; D017208:Rats, Wistar; D012995:Solubility; D014961:X-Ray Diffraction; D047392:beta-Cyclodextrins / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics*
chemical_list: D047392:beta-Cyclodextrins; C512397:thienorphine; D002047:Buprenorphine; C038119:heptakis(2,6-O-dimethyl)beta-cyclodextrin