Comparison of ketorolac 0.4% and bromfenac 0.09% at trough dosing: aqueous drug absorption and prostaglandin E2 levels.

Purpose: To compare aqueous drug concentrations and prostaglandin E(2) (PGE(2)) levels in patients treated with ketorolac 0.4% and bromfenac 0.09% at trough dosing.
Setting: Private practice, Wilkes-Barre, Pennsylvania, USA.
Methods: This single-center randomized investigator-masked clinical study comprised 56 patients having cataract surgery. Patients received 1 drop of ketorolac 0.4% or bromfenac 0.09% 6 hours and 12 hours preoperatively consistent with on-label dosing schedules. Aqueous humor was collected at the start of surgery and analyzed for concentrations of ketorolac and bromfenac using a reverse-phase high-performance liquid chromatography-mass spectroscopy system and for PGE(2) levels by competitive enzyme immunoassay.
Results: The mean aqueous PGE(2) level was 204.2 pg/mL +/- 95.5 (SD) in patients treated with ketorolac 0.4% and 263.7 +/- 90.0 pg/mL in patients treated with bromfenac 0.09%, (P = .020). The mean aqueous concentration of ketorolac and bromfenac at trough dosing was 130.5 +/- 37.8 ng/mL and 6.2 +/- 3.1 ng/mL, respectively (P = .004).
Conclusions: Higher aqueous levels and greater PGE(2) inhibition were observed in cataract surgery patients treated with ketorolac 0.4% than in patients treated with bromfenac 0.09% at trough dosing. These findings suggest that ketorolac 0.4% administered 4 times a day may provide better control of prostaglandin-mediated inflammation than bromfenac 0.09% administered twice a day.