title: Pharmacokinetics and safety of intravitreally delivered etanercept.
abstract: BACKGROUND
  The anti-inflammatory drug etanercept may be an effective therapeutic agent in diabetic retinopathy. In order to further evaluate its potential, the pharmacokinetics and safety of this drug after intravitreal delivery were investigated.
  
  
  METHODS
  After intravitreal administration of etanercept in rabbits, clinical examination, electroretinography (ERG), visually evoked potentials (VEP) and histology were evaluated. The pharmacokinetics and distribution of etanercept were analyzed using fluorescence-coupled protein at 0, 2, 4, and 8 weeks after injection in vitreous, retina, and choroid.
  
  
  RESULTS
  No adverse effects and signs of toxicity were found. Etanercept showed peak concentrations after 4 weeks in the retina and choroid.
  
  
  CONCLUSIONS
  Intravitreally delivered etanercept is safe and results in high concentrations in the retina and choroid over a long period of time.
authors.affiliation: Abteilung für Netzhaut- und Glaskörperchirurgie des Zentrums für Augenheilkunde und Zentrum für Molekulare Medizin (ZMMK), Universität zu Köln, Joseph-Stelzmann-Strasse 9, 50931 Cologne, Germany. sfauser@hgmp.mrc.ac.uk
authors.forename: Sascha
authors.initials: S
authors.lastname: Fauser
authors.forename: Hubert
authors.initials: H
authors.lastname: Kalbacher
authors.forename: Nils
authors.initials: N
authors.lastname: Alteheld
authors.forename: Kan
authors.initials: K
authors.lastname: Koizumi
authors.forename: Tim U
authors.initials: TU
authors.lastname: Krohne
authors.forename: Antonia M
authors.initials: AM
authors.lastname: Joussen
mesh_terms: D000818:Animals; D002829:Choroid / Q000187:drug effects / Q000378:metabolism*; D004596:Electroretinography; D000068800:Etanercept; D005074:Evoked Potentials, Visual; D007074:Immunoglobulin G / Q000378:metabolism* / Q000633:toxicity; D007166:Immunosuppressive Agents / Q000493:pharmacokinetics* / Q000633:toxicity; D007267:Injections; D008297:Male; D011817:Rabbits; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism*; D012160:Retina / Q000187:drug effects / Q000378:metabolism*; D014018:Tissue Distribution; D014822:Vitreous Body / Q000378:metabolism*
chemical_list: D007074:Immunoglobulin G; D007166:Immunosuppressive Agents; D018124:Receptors, Tumor Necrosis Factor; D000068800:Etanercept