Abstract
The purpose of this study was to characterize and determine the efficacy of a long-term, non-invasive gel/microsphere (GMS) eye drop for glaucoma. This novel drug delivery system is comprised of a thermoresponsive hydrogel carrier and drug-loaded polymer microspheres. In vitro release of brimonidine from the GMS drops and gel properties were quantified. A single brimonidine-loaded GMS drop was administered to 5 normotensive rabbits and intraocular pressure (IOP) was monitored for 28 days. Here we report that IOP reduction in rabbits receiving a single brimonidine GMS drop was comparable to that of rabbits receiving twice daily, standard brimonidine drops. GMS drops were retained in the inferior fornix in all animals for the length of the study. Our results suggest in vivo efficacy over 28 days from a single GMS drop and a potential decrease in systemic absorption, based on a lack of substantial IOP effects on the fellow untreated eye, compared to brimonidine twice-daily eye drops. To our knowledge, this represents the first long-term, drug-releasing depot that can be administered as a traditional eye drop.
Highlights
Failure to adhere to prescribed treatment leads to a greater number of and more frequent office visits for patients, with consequent increases in cost to the medical system
The thermoresponsive hydrogel carrier loaded with rate controlling, safe, and biodegradable polymer microspheres represent a novel, topical ocular drug delivery system capable of releasing drug over customizable and sustained periods of time
The overwhelming majority of glaucoma patients are non-adherent to their treatment regime in some way, putting them at much higher risk for vision loss[36]
Summary
Failure to adhere to prescribed treatment leads to a greater number of and more frequent office visits for patients, with consequent increases in cost to the medical system. The total loading of drug in such systems is much lower than for conventional eye drops, as with IOP reduction accomplished in our subconjunctival injection model using approximately 100 times less drug than twice-daily drops[21]. Despite these advantages, approximately 40% of patients are reluctant to receive regular subconjunctival injections[25]. The thermoresponsive hydrogel carrier loaded with rate controlling, safe, and biodegradable polymer microspheres ( referred to as gel microsphere drops, or GMS drops) represent a novel, topical ocular drug delivery system capable of releasing drug over customizable and sustained periods of time
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
