[Inhibitory effect of AA-673 eye drops on ocular provocation for Japanese cedar pollinosis].

The inhibitory effect of 0.25% AA-673 eye drops on histamine release in tears was examined by an ocular provocation test with antigen in 11 patients with Japanese cedar pollinosis during the off-season. AA-673 eye drops were administered into the right eye, while the left eye was given placebo eye drops. Five minutes later, a cedar antigen solution at 1:20 w/v was applied to the eyes. Levels of histamine in collected tears were determined by radioimmunoassay. Histamine levels in tears before, and 5 min and 10 min after provocation amounted to 0.2 +/- 0.2 ng/ml, 1.2 +/- 1.3 ng/ml and 1.3 +/- 1.6 ng/ml, respectively, while they were 0.2 +/- 0.2 ng/ml, 3.4 +/- 2.4 ng/ml and 3.6 +/- 3.6 ng/ml in the placebo-treated eyes at the same time points, showing a significant inhibitory effect of the drug on histamine release in the eyes treated with AA-673 (p less than 0.01 at 5 min; p less than 0.05 at 10 min). Inhibition rates of AA-673 eye drops on histamine release were 73.0% at 5 min and 69.6% at 10 min after provocation, indicating the excellent effect of this preparation in inhibiting histamine release. From the above findings it is considered that 0.25% AA-673 eye drops are an effective new therapeutic agent for Japanese cedar pollinosis.