Abstract
Purpose :
To investigate the influence of the patient factors on ocular pharmacokinetics by post hoc pooled analysis of clinical studies of brimonidine related eye drops.
Methods :
Data from 3 clinical studies were used. The subjects were 42 patients who were scheduled for vitrectomy and received brimonidine related eye drops (0.1% brimonidine tartrate ophthalmic solution, 0.1% brimonidine tartrate and 0.68% timolol maleate fixed-combination ophthalmic solution or 0.1% brimonidine tartrate and 1% brinzolamide fixed-combination suspension) twice daily for 1 week. We analyzed the effects of patient factors such as sex, state of lens, age, corneal thickness, corneal endothelial cell density, tear secretion, axial length of the eye, height, weight and body mass index (BMI) on the concentrations of brimonidine, timolol and brinzolamide in the aqueous humor and vitreous after topical application. Wilcoxon rank sum test was used for comparison between two groups (sex, state of lens). Correlations were estimated by Spearman’s rank correlation coefficient method.
Results :
The drug concentrations in the aqueous humor and vitreous were not significantly different regardless of sex and the presence or absence of lens. There was a significantly positive correlation between age and the concentrations in the aqueous humor of brimonidine (r = 0.3948, p = 0.012) and brinzolamide (r = 0.6809, p = 0.030), while timolol was close to significance (r = 0.6425, p = 0.086). No significant correlation was found between the drug concentrations in the aqueous humor and vitreous with corneal thickness, corneal endothelial cell density, tear secretion, axial length of the eye, height. Only the timolol concentration in the vitreous was tendency to negatively correlate with weight and BMI (weight, r = −0.8333, p = 0.010; BMI, r = −0.5714, p = 0.139).
Conclusions :
This study examined whether or not each patient factor affected the intraocular penetration of drugs following topical administration. Findings of this study demonstrate the necessity of the formulation design of eye drops and the drug therapy in consideration of individual differences in ocular pharmacokinetics.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.