Efficacy and safety of brimonidine, dorzolamide and latanoprost as adjunctive therapy in primary open angle glaucoma.

A double-blind, randomised, controlled trial was carried out to evaluate the efficacy and safety of brimonidine, dorzolamide and latanoprost as an adjunctive therapy in patients with primary open angle glaucoma (POAG). A total of 200 males and 72 females with POAG uncontrolled with previous glaucoma therapy were randomly allocated to receive topical brimonidine 0.2% b.d. (n = 90), topical dorzolamide 2% b.d. (n=91) or topical latanoprost 0.005% o.d. (n = 91). One year post treatment, the mean percentage reduction in intraocular pressure (IOP) between the three groups was statistically significant (p < 0.0001). In an intergroup comparison of efficacy, there was a statistically significant difference between the brimonidine and dorzolamide groups (p = 0.018) and between the dorzolamide and latanoprost groups (p = 0.76) but the efficacy of brimonidine was not significantly higher than latanoprost in the brimonidine and latanoprost groups (p = 0.002). Patients experiencing mild to severe side-effects were statistically similar in the three groups. On an inter-drug comparison of side-effects, we found no statistically significant difference in the brimonidine and latanoprost groups (p = 0.25); and the brimonidine and dorzolamide groups (p = 0.067), while the number of side-effects with latanoprost was significantly higher in the dorzolamide and latanoprost groups (p<0.003). All three drugs caused a significant reduction in the mean IOP from pretreatment values. The brimonidine group had a higher number of patients experiencing severe side-effects necessitating alteration of therapy.