Poly-epsilon-caprolactone intravitreous devices: an in vivo study.
OBJECTIVE
The objective of this study was to evaluate the long-term safety and pharmacokinetic profile of a dexamethasone-loaded poly-epsilon-caprolactone (PCL) intravitreous implant.


METHODS
The PCL devices were prepared by compression and were inserted into the vitreous of pigmented rabbits. At different time points, vitreous samples were retrieved, and dexamethasone concentration was analyzed by high-performance liquid chromatography. The biodegradation of the implants was evaluated by scanning electron microscopy, and the dexamethasone remaining was evaluated at the end of follow-up. Clinical and histologic examinations were performed to evaluate the implant's tolerance.


RESULTS
The PCL implant allows for a controlled and prolonged delivery of dexamethasone in rabbits eyes since it released the drug within the therapeutic range for at least 55 weeks. At 55 weeks approximately 79% of the drug was still present in the implant. Biodegradation study showed that PCL implants degradation is very slow. Clinical and histologic observations showed that the devices were very well tolerated in the rabbit eye.


CONCLUSIONS
This study demonstrates the feasibility and tolerance of intravitreous PCL drug delivery systems, which can offer a wide range of applications for intraocular drug delivery because of their controlled and prolonged release over months or even years.
Silva-Cunha
Armando
A
Faculty of Pharmacy of the Federal University of Minas Gerais, Belo Horizonte, Brazil.
Fialho
Silvia Ligorio
SL
Naud
Marie-Christine
MC
Behar-Cohen
Francine
F
D020341:Absorbable Implants; D000818:Animals; D000869:Anterior Eye Segment / Q000473:pathology; D001672:Biocompatible Materials; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid; D003907:Dexamethasone / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D004337:Drug Carriers; D004343:Drug Implants; D005240:Feasibility Studies; D006207:Half-Life; D007429:Intraocular Pressure / Q000187:drug effects; D008855:Microscopy, Electron, Scanning; D011091:Polyesters; D011817:Rabbits; D014822:Vitreous Body / Q000378:metabolism* / Q000473:pathology
D001672:Biocompatible Materials; D004337:Drug Carriers; D004343:Drug Implants; D011091:Polyesters; C016240:polycaprolactone; D003907:Dexamethasone