Ocular Pharmacokinetics of a Single Dose of Bromfenac Sodium Ophthalmic Solution 0.1% in Human Aqueous Humor

Abstract

The aim of this study was to evaluate the ocular pharmacokinetics of a single dose of bromfenac sodium ophthalmic solution 0.1% in subjects undergoing routine cataract surgery with intraocular lens implantation. An open-label, phase II confirmatory study of 54 subjects undergoing cataract surgery with intraocular lens implantation. A single drop of bromfenac sodium ophthalmic solution 0.1% was administered at 30, 60, 90, 120, 180, or 240 min prior to the initiation of cataract surgery. Samples of aqueous humor were aspirated through a paracentesis and analyzed by using high-performance liquid chromatography. Based upon these data, predicted concentrations of bromfenac in the aqueous humor over 24 h were generated by using computer simulation and compared with the IC(50) for bromfenac as a measure of anti-inflammatory efficacy. Peak aqueous-humor concentrations of bromfenac occurred between 150 and 180 min following ophthalmic dosing, with a mean concentration of 78.7 ng/mL. The level of bromfenac decreased in a log-linear fashion with an elimination-rate constant of 1.4. Bromfenac remained above the IC(50) value of cyclo-oxygenase-2 (COX-2) during the evaluated time points and over the 12-h dosing interval, using a computer model of extrapolated time points and assuming first-order elimination. Pharmacokinetic modeling, based upon samples collected over 240 min after a single dose of bromfenac sodium ophthalmic solution 0.1% suggests that aqueous-humor concentrations remain at clinically effective levels (above its IC(50) value for COX-2) for over 12 h. Based upon this rationale, these results supported clinical trials that demonstrated the efficacy of twice-daily dosing of bromfenac sodium ophthalmic solution 0.1% to manage patients with postoperative ocular pain and inflammation.