Abstract
Purpose:
Covalent immobilisation of antimicrobial peptide melimine onto contact lenses can produce broad spectrum antimicrobial lenses. The aim of this study was to investigate the performance of melimine-coated contact lenses in a human clinical trial.
Methods:
Melimine was covalently attached to the contact lens surface (etafilcon A) via EDC coupling. A prospective, randomised, double-masked, contralateral,1 day clinical trial was used to evaluate subjective responses and ocular physiology during contralateral wear of melimine-coated (test) and uncoated (control) lenses. Delayed reactions were monitored during follow-up visits after 1 and 4 weeks. Ex-vivo retention of antimicrobial activity of worn lenses were assessed by reduction in numbers of viable Pseudomonas aeruginosa 6294 and Staphylococcus aureus 31.
Results:
No differences were observed in wettability and surface deposition between test and control lenses (p >0.05). Lens fitting centration, movement, tightness, and corneal coverage were comparable between the test and control lenses. There were no significant differences between test and control lenses for bulbar, limbal or palpebral redness or conjunctival staining (p >0.05). Mean corneal (extent, depth and type) staining was higher for test lenses compared to control lenses (p< 0.05). There was no difference in subjective responses for lens comfort, dryness and awareness (p< 0.05). No delayed reactions were associated with the test lenses. Worn test lenses retained more than 1.5 log inhibition against both bacterial types.
Conclusions:
This study provides the first evidence to indicate antimicrobial peptide-coated contact lenses can be worn safely by humans. Melimine-coated lens wear was uneventful except that it was associated with higher corneal staining, similar in presentation to solution-induced corneal staining (extent and depth). The melimine-coated lenses retained high antibacterial activity following wear.
Keywords: 477 contact lens •
422 antibiotics/antifungals/antiparasitics •
464 clinical (human) or epidemiologic studies: risk factor assessment