Abstract
Purpose :
To compare the distribution characteristic and ocular pharmacokinetics of norvancomycin in ocular tissues of anterior segment between continuous topical ocular instillation and hourly administration of eye drop in rabbits
Methods :
Sixty rabbits were randomly divided into 2 groups: continuous topical ocular instillation drug delivery (CTOIDD) group and eye drop (control) group. In the CTOIDD group, norvancomycin solution (50mg/ml) was perfused to the ocular surface using CTOIDD system at 2ml/h up to 10 hours and the same solution was administrated one drop (50μl) per hour for 10h in the control group. Animals were sacrificed at 2, 4, 6, 10 and 24 hours and ocular tissues and plasma were obtained promptly. The concentration of norvancomycin in the conjunctiva, cornea, aqueous humour, iris, ciliary body and plasma were measured by HPLC-PDA method. The pharmacokinetics parameters were calculated by Kinetica 5.1
Results :
The highest concentration of norvancomycin for the CTOIDD group and control group were 2105.45±919.89μg/g and 97.18±43.14μg/g in cornea, 3033.92±1061.95μg/g and 806.99±563.02μg/g in conjunctiva, 1570.19±402.87μg/g and 46.93±23.46μg/g in iris, 181.94±47.11μg/g and 15.38±4.00μg/g in ciliary body, 29.78±4.90μg/ml and 3.20±1.48μg/ml in aqueous humour, 26.89±5.57μg/ml and 1.90±1.87μg/ml in plasma. The mean norvancomycin levels significantly increased in all time points in cornea, iris and ciliary body (p＜0.05) in the CTOIDD group. The AUC0-24 in the CTOIDD group were 27543.70μg*h/g in cornea, 32514.48μg*h/g in conjunctiva, 8631.05μg*h/g in iris, 2194.36μg*h/g in ciliary body and 343.94μg*h/ml in aqueous humour which was higher than the eye drop group in all tissues
Conclusions :
Since continuous instillation with CTOIDD could reach significantly higher concentration of norvancomycin and sustained for a longer period compared with hourly administration of eye drop, CTOIDD can be a possible efficient method to manage with the bacterial keratitis
This is a 2020 ARVO Annual Meeting abstract.