A new vitreal drug delivery system using an implantable biodegradable polymeric device.

Abstract

PURPOSE: The authors evaluated the feasibility of using an implantable biodegradable polymeric device to deliver drugs into the vitreous humor. METHODS: Two types of devices were prepared by compression-molding polymers of poly(DL-lactic acid) of two different molecular weights. The molecular weights of the poly(DL-lactic acid) used were 5,600 (device-1) and 9,100 (device-2). Sodium fluorescein (NaF) served as a hydrophilic drug marker. The release of the dye from the devices was studied in vitro. The intravitreal kinetics of NaF was evaluated in rabbits in vivo by fluorophotometry. The eyes were evaluated electrophysiologically and histologically to determine if there were toxic effects. RESULTS: Device-1 and device-2 released NaF for more than 25 and 45 days, respectively, in vitro. Detectable concentrations of NaF were present in the vitreous up to 17 days (device-1) and 28 days (device-2). Both types of devices were well tolerated, with no noted toxic effects. CONCLUSIONS: These results suggested that this device may be a potentially effective system to deliver drugs in the vitreous.