A DOUBLE-MASKED COMPARISON OF THE INTRAOCULAR-PRESSURE REDUCING EFFECT OF LATANOPROST 0.005-PERCENT AND 0.001-PERCENT ADMINISTERED ONCE-DAILY IN OPEN-ANGLE GLAUCOMA AND OCULAR HYPERTENSION

Aim-To compare the intraocular pressure (IOP) reducing effect of latan oprost 0.005% and 0.001%. Methods-Twenty four patients with glaucoma o r ocular hypertension were randomised into two groups. Twelve patients (group 1) were given latanoprost 0.005% once daily for 4 weeks and th en latanoprost 0.001% once daily for the following 4 weeks. Twelve pat ients (group 2) were given latanoprost 0.001% once daily for 4 weeks a nd then latanoprost 0.005% for the following 4 weeks. Results-There wa s a significant IOP reduction from baseline in both groups on day 28 a s well as on day 56. When the results from both groups were used for c alculations, the mean IOP reduction from baseline after 4 weeks of tre atment with latanoprost 0.005% (day 28 or 56) was 9.6 (SD 3.3) mm Hg ( 35.0%). After 4 weeks of treatment with latanoprost 0.001%, the IOP re duction (day 28 or 56) was 7.6 (3.4) mm Hg (27.7%). The difference in IOP reduction between the two concentrations was 2.0 (2.3) mm Hg (p<0. 001). Conclusions-Latanoprost 0.005% was more effective than latanopro st 0.001% in reducing IOP. Even the lower concentration was surprising ly effective, and potentially may be of importance for use in clinical practice. Furthermore, it is at present unknown whether the increase in iris pigmentation seen in certain patients treated with latanoprost 0.005% is dose dependent and might be less pronounced with latanopros t 0.001%. Long term studies with a larger number of patients are requi red in order to answer this question.