Alcaftadine was also superior in the category of subjects with minimal itching (less than 1 on a 4-point scale); in 95 grass-allergic subjects, 38 (79%) subjects who had received alcaftadine had a low score versus 25 (54%) of those who received olopatadine.
In the study of tree-allergic subjects 24 hours after dosing (n=16), results 3 minutes post-CAC showed that the mean difference between alcaftadine (mean itching score of 0.50) and olopatadine (mean itching score of 1.38) was -0.88 (p=0.135).
The change from baseline was -2.4 for alcaftadine versus -1.1 for olopatadine (p=0.048), which corresponded to a percentage change from baseline of -83.3% for alcaftadine versus -41.4% for olopatadine (p=0.045). Five patients treated with alcaftadine (83%) versus 2 (33%) who had received olopatadine reported minimal itching of less than 1 on the 0-4 itching scale (p=0.242).
1Ono SJ, Lane K. Comparison of effects of alcaftadine and olopatadine on conjunctival epithelium and eosinophil recruitment in a murine model of allergic conjunctivitis. Drug Design, Development and Therapy. 2011;5:77-84.