Abstract
Abstract: :
Purpose: To study the ocular bioavailability of a triple dose, single application of Sodium Fluorescein to the anterior segment of healthy volunteers from a novel lyophilisate. Method: Fluorescein methocel was deposited on sterilized flexible hydrophobic polytetrafluoroethylene (PTFE) carrier strips and freeze-dried under aseptic conditions. The fluorescein dose of the lyophilisate was 204µg corresponding to three conventional, preservative-free eye drops of 40µl Fluorescein SETM 0.17% (68µg) (Alcon). In a randomised, open-label study 22 healthy volunteers applied the lyophilisate to one eye (+1min.) and three consecutive eye drops (+1, +16, +31 min.) of the fluorescein ophthalmic solution to the fellow eye. Identical doses were reached at +45 minutes. Fluorophotometry was performed (Fluorotron Master IITM Ocumetrics, USA) before and +15, 30, 45, 60, 120, 180, 240, 300, 360, 420 minutes after application. The fluorescein concentrations of cornea (C) and mid anterior chamber (AC) were analysed by paired t-test (SPSS). Results: Mean cornea and AC values (ng/ml) were significantly higher (p<0.001) in the lyophilisate group for up to 7 hours after application with the exception of +45 minutes. The mean corneal bioavailability of the lyophilisate was up to 11 times higher compared with three conventional eye drops. Cornea: mean fluorescein conc.: ng/ml Conclusion: A triple dose can be delivered to the human eye with a single lyophilisate and results in a significantly better bioavailability for up to 7 hours. Our data underline that lyophilisates are a favourable alternative to conventional eye drops. Advantages: significantly better bioavailability, no preservatives, no pH-adjustment, easy handling, less systemic side effects. P
Keywords: 318 anterior segment • 357 clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • 514 pharmacology