Poly(lactic-co-glycolic) Acid as a Slow-Release Drug-Carrying Matrix for Methotrexate Coated onto Intraocular Lenses to Conquer Posterior Capsule Opacification

Abstract

PURPOSE: Posterior capsule opacification (PCO) still represents the main long-term complication of cataract surgery. Research into pharmacologic PCO prophylaxis is extensive. One promising candidate drug is methotrexate (MTX). Our aim is to determine the in vitro feasibility of MTX-loaded poly(lactic-co-glycolic) (PLGA) biomatrices sprayed on intraocular lenses (IOLs) as a drug-delivery implant. METHODS: Hydrophilic and hydrophobic acrylic IOLs were spray-coated with MTX-loaded PLGA. Unsprayed, solvent only, and solvent-PLGA-sprayed IOLs served as controls. All IOLs were evaluated for their growth-inhibiting properties in an in vitro anterior segment model and the ex vivo human capsular bag. The release kinetics of MTX from the IOLs was determined. The toxicity of MTX on corneal endothelial cells was evaluated by using a dye reduction colorimetric assay. MTX was also used in a scratch assay. RESULTS: MTX-PLGA-IOL showed a significant difference in cell proliferation and migration compared with all controls in the anterior segment model (p < 0.001) and in the human capsular bag model (p = 0.04). No difference in viability was observed on corneal endothelial cells (p = 0.43; p = 0.61). MTX significantly inhibited cells in the scratch assay (p = 0.02). At all measured points, the released MTX dose remained above EC50 and below the toxic dose for the endothelium. CONCLUSIONS: In view of the strong inhibition of PCO in vitro with the lack of toxic effects on a corneal cell line, MTX encapsulating microspheres seem to be a promising method for modifying IOL.