Ketorolac tromethamine ophthalmic solution 0.45%, a third-generation formulation of the nonsteroidal anti-inflammatory drug, had a highly beneficial effect on visual acuity after cataract surgery in a recent study.
Twice-daily application of the drug was well tolerated and effective in reducing pain and inflammation, said Eric D. Donnenfeld, MD, at the annual meeting of the American Society of Cataract and Refractive Surgery.
"NSAIDs are used to alleviate ocular inflammation and pain after cataract surgery," said Dr. Donnenfeld, founding partner of Ophthalmic Consultants of Long Island, Rockville Centre, NY and Connecticut, and professor of ophthalmology at New York University Medical Center, New York.
The important changes in the formulation of the drug were the addition of carboxymethylcellulose; the absence of preservatives, surfactants, and chelating agents; and a decrease in pH from 7.4 to 6.8. These factors resulted in higher bioavailability of the drug by two- to three-fold in the ocular tissues.
Dr. Donnenfeld and colleagues conducted two randomized, multicenter, double-masked, vehicle-controlled studies in which they studied the efficacy and safety of ketorolac 0.45% instilled twice daily for relieving pain and inflammation in patients undergoing cataract surgery.
The investigators also looked at patients' recovery of VA.
The patients underwent uncomplicated, extracapsular phacoemulsification with posterior chamber implantation of an IOL. Ketorolac 0.45% or the vehicle was instilled twice daily starting 1 day preoperatively and continuing for 14 days after surgery.
The investigators looked at the percentage of patients who had an increase in their baseline best-corrected visual acuity (BCVA) of 3 or more lines, the percentage with a summed ocular inflammation score of 0 for anterior chamber cell and flare on day 14, and the percentage without pain 24 hours after surgery.
The patients were evaluated postoperatively on days 1, 3, 7, and 14. A total of 511 patients were included in the two studies, he said.
Baseline median BCVA in the ketorolac 0.45% group (n = 301 to 315) was 20/40 and 20/50 in the vehicle group (n = 116 to 155). The difference between the two was not significant (p = 0.321).
Dr. Donnenfeld said that a significantly (p = 0.02) higher percentage of patients treated with ketorolac 0.45% than those treated with vehicle had an improvement in the BCVA of 3 or more lines compared with baseline on days 7 and 14 postoperatively (54.4% compared with 39.1% and 60.5% and 44.0%, respectively).
He also said that the rates of the drug's adverse effects on the cornea (including corneal edema, corneal abrasion, and corneal striae) and macular edema were 5.2% (17/330) in the ketorolac group and 8.6% (14/163) in the vehicle group. There was no significant (p = 0.139) difference between the groups.