Creation of a drug-coated glaucoma drainage device using polymer technology in vitro and in vivo studies

Abstract

Objective: To create and test a slow-release antifi-brotic drug-coated glaucoma drainage device using in vitro and in vivo experiments. Methods: A slow-release device incorporating mitomycin C in poly(2-hydroxyethyl methacrylate) disks was developed using redox-polymerization techniques. A standardized preparation of this drug delivery device wasattached to the Ahmed glaucoma valve (model FP7; New World Medical, Inc, Rancho Cucamonga, California). Semicircular disks (5 X 6 mm) of P(HEMA)-mitomycin C containing varying concentrations of mitomycin C pergram dry weight of the gel were attached to the lower half of an Ahmed glaucoma valve plate. Water was pumped through the modified Ahmed glaucoma valve at a rate comparable to that of aqueous humor outflow, and mitomycin C release was measured. Modified and unmodified Ahmed glaucoma valves were implanted in a rabbit model, and drug release and fibrosis were assessed after 3 months.Results: The P(HEMA)-mitomycin C device released mitomycin C in vitro over 1 to 2 weeks. Studies in rabbits revealed that mitomycin C was released from the disks during the 3-month implantation. Histologic analysis demonstrated a significant reduction in inflammatory reaction and fibrosis in the resulting blebs. Conclusion: Our slow-release drug-coated glaucoma drainage device decreased fibrosis and inflammation in the resulting bleb in a rabbit model. Clinical Relevance: This device could reduce the failure rate of glaucoma drainage devices. © 2009 American Medical Association. All rights reserved.