COMPARISON OF THE EFFICACY AND SAFETY OF 2-PERCENT DORZOLAMIDE AND 0.5-PERCENT BETAXOLOL IN THE TREATMENT OF ELEVATED INTRAOCULAR-PRESSURE

A multicenter, parallel-design, randomized, double-masked study was co nducted to compare the efficacy and safety of 2% dorzulamide with thos e of 0.5% betaxolol in the treatment of elevated intraocular pressure (IOP). A total of 311 adults with ocular hypertension or open-angle gl aucoma were randomly allocated to receive either 2% dorzolamide admini stered topically TID or 0.5% betaxolol administered topically BID plus placebo administered topicaIly QD for 12 weeks. After the washout of previous ocular hypotensive drugs, patients with IOP greater than or e qual to 23 mm Hg in at least one eye at 10 AM or 4 PM On study day 1 w ere randomly allocated to receive one of the study treatments. Through out the study, IOP was measured 2 and 8 hours after instillation of st udy medication for the morning peak effect (hour 2) and afternoon trou gh effect (hour 8). After 12 weeks of therapy, the mean change in IOP was not significantly different between the dorzolamide and betaxolol treatment groups at hour 8 (-3.6 mm Hg in both groups) or hour 2 (-5.4 vs -5.3 mm Hg, respectively). The differences between treatments land 95% CIs associated with these differences) in mean IOP changes from b aseline were 0.02 mm Hg (-0.870 to 0.901) for hour 8 and -0.14 mm Hp ( -0.959 to 0.685) for hour 2. The ocular adverse experience (AE) most f requently reported by patients was ocular burning and/or stinging, and the most frequently reported nonocular AEs were taste perversion, upp er respiratory infection, and headache. Only the incidence of taste pe rversion was significantly different between treatment groups (14.6% f or the dorzolamide group and 0.0% for the betaxolol group). Two percen t of patients in each treatment group discontinued the study due to AE s. This study confirmed the similar IOP-lowering effect of 2% dorzolam ide and 0.5% betaxolol. Both treatments were generally well tolerated, and their safety profiles were similar.