title: In-vivo evaluation of prolonged release bilayer tablets of anti-Parkinson drugs in Göttingen minipigs.
abstract: OBJECTIVE
  Patients with Parkinson's disease can benefit from controlled released levodopa dosage forms since there is a clear clinical advantage in obtaining sustained plasma concentrations. The purpose of this study was to obtain a tablet that prolonged the release of levodopa.
  
  
  METHODS
  A novel bilayer tablet, consisting of an immediate release layer containing nebicapone (100 mg) and an erosion-matrix type prolonged release layer containing levodopa (100 mg) and carbidopa (25 mg) was developed (LCN PR). A pharmacokinetic study in Göttingen minipigs was performed to evaluate this formulation.
  
  
  RESULTS
  LCN PR tablets prolonged the in-vitro release of levodopa in HCl 0.1 m for more than 3 h. In-vivo plasma levodopa levels peaked at a later time point with LCN PR tablets as compared with that obtained with Sinemet 100/25 (2.7 vs 0.5 h). Nebicapone increased the maximum plasma concentration and area under the plasma concentration-time curve values for levodopa.
  
  
  CONCLUSIONS
  The results obtained suggested that LCN PR tablets may have decreased the number of tablets and daily intake in the treatment of patients with Parkinson's disease.
authors.affiliation: Pharmaceutical Technology Department, Faculty of Pharmacy, University of Porto, Portugal. paulo.silva@ff.up.pt
authors.forename: José Paulo
authors.initials: JP
authors.lastname: Sousa e Silva
authors.forename: José S
authors.initials: JS
authors.lastname: Lobo
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Bonifácio
authors.forename: Rita
authors.initials: R
authors.lastname: Machado
authors.forename: Amílcar
authors.initials: A
authors.lastname: Falcão
authors.forename: Patrício
authors.initials: P
authors.lastname: Soares-da-Silva
mesh_terms: D000098:Acetophenones / Q000494:pharmacology*; D000818:Animals; D000978:Antiparkinson Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D019540:Area Under Curve; D002230:Carbidopa / Q000008:administration & dosage; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D007980:Levodopa / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D013552:Swine; D013556:Swine, Miniature; D013607:Tablets; D013678:Technology, Pharmaceutical
chemical_list: D000098:Acetophenones; D000978:Antiparkinson Agents; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D013607:Tablets; D007980:Levodopa; D002230:Carbidopa; C433466:nebicapone