Corneal delivery of moxifloxacin and dexamethasone combination using drug-eluting mucoadhesive contact lens to treat ocular infections

The important causes of loss of vision are ocular infections, including keratitis and conjunctivitis. Attaining an adequate concentration of topically applied antibiotics to prevent or treat infections within the cornea is challenging. The study aimed to design and develop a drug-eluting polymeric contact lens for the effective delivery of moxifloxacin (MF) and dexamethasone (DM). The polymeric contact lens was prepared using chitosan, glycerol, and polyethylene glycol. MF and DM were loaded into the contact lens, both separately and in combination. The MF and DM loaded contact lenses were characterized for thickness, swelling index, surface topography, and mucoadhesion strength. Furthermore, studies were performed to understand the in vitro drug release behavior, ex vivo corneal permeation, and in vitro and in vivo antimicrobial activity. The drug-loaded contact lens was compared with the standard drug solutions. The physical characteristics of the polymeric contact lens were similar to the commercially available contact lens. Compared to the topically applied standard drug solutions, the drug-loaded contact lens showed significantly (p < 0.05) greater corneal drug distribution after 24 h incubation. In vitro and in vivo antimicrobial activity of the MF loaded contact lens was superior to the standard drug solution. In vivo drug distribution studies showed greater tissue concentration of MF in cornea, sclera, and aqueous humor with contact lens application compared with drug solutions. Overall, the polymeric contact lens was efficient in delivering MF and DM at required therapeutic concentrations. The findings from the present study show that drug-eluting contact lenses could be used in post-operative conditions to prevent ocular infections.