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Updated: Aug 25, 2026

Use of Rabbit Eyes in Pharmacokinetic Studies of Intraocular Drugs
Published on: July 23, 2016
Pharmacokinetics and safety of intravitreally delivered etanercept
Sascha Fauser1, Hubert Kalbacher, Nils Alteheld
1Abteilung 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
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.
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