This prospective phase I clinical trial evaluated the safety of intravitreal ketorolac 4 mg in patients with chronic uveitis and chronic inflammation or macular edema. This is believed to be the first study investigating the safety of intravitreal ketorolac in humans. They observed no adverse ocular effects after a single intravitreal injection of ketorolac (4 mg), and the treatment appeared to be well tolerated.
However, further clinical trials are required to determine whether this is an effective treatment for posterior segment inflammation and a safer alternative to corticosteroids in patients at increased risk of cataract formation and increased IOP. In a previous study, high levels of intravitreal ketorolac and another NSAID, diclofenac, were well tolerated in an animal model.
The current study involved 10 adult patients (10 eyes) with chronic inflammation and/or macular edema who had failed previous treatment or could not tolerate corticosteroids. They each received a single intravitreal injection of ketorolac (4 mg) and were followed for 90 days.
Two patients had active inflammation at the time of injection, and both showed a reduction in inflammation within one week. Four of the other eight patients had either reduced central subfield thickness or reduced leakage by fluorescein angiography within the first week after treatment, although this improvement did not persist throughout the whole study.
The results of this study suggest that in patients with recurrent uveitis and macular edema, intravitreal ketorolac may be a reasonable treatment option, particularly in patients known to develop elevated IOP from topical steroids or in phakic patients at risk for cataract formation.
However, a limiting factor for this medication is its short half-life. Therapeutic levels of ketorolac are present only for two days in the vitreous and even less time in the retina. As suggested by the study's authors, development of a sustained-release device that would allow drug delivery over an extended period would be more useful and practical in the clinical setting.