Comparison of the topical ocular antiallergic efficacy of emedastine 0.05%ophthalmic solution to ketorolac 0.5% ophthalmic solution in a clinical model of allergic conjunctivitis

Purpose: To compare the clinical efficacy of emedastine ophthalmic solution to that of ketorolac ophthalmic solution using a conjunctival allergen cha llenge model. Methods: The conjunctival allergen challenge model was used in this randomi zed, double-masked, single center, crossover study. The titer of allergen t hat elicited a positive allergic reaction was selected. After at least 14 d ays, 36 subjects were randomized into two groups of 18 to receive either em edastine in one eye and placebo in the contralateral eye, or ketorolac in o ne eye and placebo in the contralateral eye. Ten minutes after drug instill ation, subjects were challenged with antigen. At 3, 10 and 20 minutes follo wing challenge subjects graded ocular itching and were assessed for hyperem ia in conjunctival, ciliary, and episcleral vessel beds. Approximately 14 d ays later, subjects received the alternate treatment in one eye and placebo in the contralateral eye, They were again challenged with allergen and the ir responses were rated in the same manner. Ocular discomfort was assessed by the subjects after administration of each study drug, Results: Emedastine significantly (p<0.05) inhibited ocular itching and red ness in vascular beds following topical ocular administration. In contrast, ketorolac failed to significantly inhibit ocular itching or redness in thi s study, Patient assessment of comfort indicated emedastine was significant ly (p<0.05) more comfortable than ketorolac upon topical ocular administrat ion. Conclusion: Emedastine is superior to ketorolac in controlling itching and redness, the cardinal symptom and sign of allergic conjunctivitis.