title: A case study exploring the impact of an oxygen barrier coating on formulation stability, in-vitro dissolution and bioperformance.
abstract: OBJECTIVE
  The impact of a carmellose sodium (sodium carboxymethycellulose)-based coat (Opaglos 2) on the stability of an oxygen-sensitive compound A and in-vitro dissolution and bioperformance of compound B has been investigated.
  
  
  METHODS
  Tablets containing compounds A and B were coated with various weight gains of Opaglos 2 and a comparative elegance coating (poly(vinyl alcohol)-based Opadry II). Film-coated tablets were assessed for oxidative degradation under accelerated stability conditions (30°C/65% RH and 40°C/75% RH).
  
  
  RESULTS
  An apparent rank order of restriction of oxygen (O(2) ) permeability afforded by the coatings was observed, with only higher Opaglos 2 coating weight gains (6 and 8% w/w) providing adequate oxidative degradation stability for up to 52 weeks. Improved stability at the higher coating weight gains was attributed to incomplete polymeric film formation at lower coating weight gains. The 6% and 8% w/w Opaglos 2 formulations showed dissolution retardation compared with elegance-coated formulations in USP dissolution apparatus II, predicting significant impact on formulation bioperformance. However, pharmacokinetic studies in Beagle dogs showed similar bioperformance for all formulations.
  
  
  CONCLUSIONS
  The Opaglos 2 coating system evaluated in these studies afforded adequate protection from oxidative degradation with no negative impact on bioperformance as compared to elegance coating. However, further studies are needed using several compounds to assess the broader applicability of these coatings.
authors.affiliation: Analytical Sciences, MSD Ltd, Hoddesdon, Hertfordshire, UK.
authors.forename: James C
authors.initials: JC
authors.lastname: Mann
authors.forename: Amitava
authors.initials: A
authors.lastname: Mitra
authors.forename: Samuel R
authors.initials: SR
authors.lastname: Pygall
mesh_terms: D000818:Animals; D019540:Area Under Curve; D001682:Biological Availability; D002266:Carboxymethylcellulose Sodium / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004285:Dogs; D004355:Drug Stability; D008297:Male; D010100:Oxygen / Q000737:chemistry*; D012995:Solubility; D013608:Tablets, Enteric-Coated / Q000737:chemistry*; D053719:Tandem Mass Spectrometry; D013678:Technology, Pharmaceutical
chemical_list: D013608:Tablets, Enteric-Coated; D002266:Carboxymethylcellulose Sodium; D010100:Oxygen