Effect of Coherin™ on intraocular pressure, pupil size and heart rate in the glaucomatous Beagle: a pilot study.

Abstract

OBJECTIVE: To evaluate effects of Coherin&#x2122; on intraocular pressure (IOP), pupil size (PS), and heart rate (HR) in glaucomatous Beagles in single-dose studies in a pilot study. MATERIALS AND METHODS: Intraocular pressure, PS, and HR were measured in eight glaucomatous Beagles. One randomly chosen eye received single 50&#x2003;&#x3bc;L doses of differing concentrations of Coherin&#x2122; (treated eye) or vehicle (placebo-treated eye), and the fellow eye served as the untreated control. After the first measurements, a single dose of either Coherin&#x2122; or sterile water vehicle was instilled in the drug and placebo eyes, respectively. RESULTS: The mean &#xb1; SEM diurnal changes in IOP after 0.005%, 0.01%, 0.2%, 0.284%, 1%, 2%, and 4% topical Coherin&#x2122; once daily were 7.6 &#xb1; 3.2 mmHg, 15.5 &#xb1; 5.3 mmHg, 11.2 &#xb1; 4.4 mmHg, 11.8 &#xb1; 4.4 mmHg, 19.1 &#xb1; 3.8 mmHg, 5.0 &#xb1; 1.8 mmHg, and 8.8 &#xb1; 2.8 mmHg, respectively. The declines in IOP were significantly different (P < 0.05) from the untreated control eyes with the 0.2% and 0.284% Coherin&#x2122;-treated eyes and suggestive for 1% Coherin&#x2122; concentrations. No signs of irritation, significant PS, and HR changes were detected in the Coherin&#x2122;-treated eyes. CONCLUSION: Of seven different concentrations, 2% and 0.248% Coherin&#x2122; produced significant declines in IOP in the glaucomatous beagle in single-dose studies when compared to both untreated control and placebo-treated eyes. One percent Coherin&#x2122; solution produced significant IOP decreases compared with the placebo-treated eye but not the untreated control eyes. No local ocular irritation, PS and HR changes were observed in Coherin&#x2122;-treated eyes. This pilot study suggests that topical Coherin&#x2122; has potential as an ocular hypotensive agent.