Comparative studies on topical lomefloxacin and ciprofloxacin on ocular kinetic and experimental corneal ulcer

Fluoroquinolones are antimicrobial agents that have a broad spectrum of activity and that are widely used against many of the ocular pathogens responsible for conjunctivitis, blepharitis, corneal ulcers, etc. The aim of our study was to compare the ocular pharmacokinetics of ciprofloxacin (0.3% w/v) and lomefloxacin (0.3% w/v) by HPLC after a single application of 50 microl topically. The study was also extended to compare their efficacy in experimentally-induced corneal ulcers. In ocular kinetic studies, lomefloxacin showed nearly 10 times more ocular bioavailability in aqueous humor as compared to ciprofloxacin. Lomefloxacin showed a Cmax of 1.62 microg/ml at the Tmax of 1 hr whereas ciprofloxacin showed a Cmax of 102.8 ngs/ml at the Tmax of 1 hr. Lomefloxacin was found to have significant efficacy in the healing of Staphylococcus aureus-induced corneal ulcers and associated lesions. Moreover, aqueous formulation oflomefloxacin showed a good compatibility at neutral pH. The results of our study indicate that a suitable treatment regimen with lomefloxacin (0.3%) therapy could be an excellent therapeutic alternative over ciprofloxacin in bacterial keratitis.