Purpose:
To evaluate the mid–term efficacy of the dorzolamide 2%/timolol maleate 0.5% fixed combination versus latanoprost 0.005% in patients with primary open–angle glaucoma or ocular hypertension.
Methods:
Patients were randomized to either the dorzolamide/timolol maleate fixed combination dosed twice daily or to placebo dosed every morning and latanoprost dosed every evening following a six–week washout period. Patients were dosed in a single–masked fashion for six months on their first treatment and then crossed over to the opposite treatment for an additional six months. At the baseline visit, as well as at the end of each treatment period, patients underwent diurnal curve testing by Goldmann applanation tonometry at 06:00, 10:00, 14:00, 18:00, 22:00 and 02:00 hours.
Results:
Fifty–three patients were included in the study who had an average 24–hour baseline intraocular pressure (IOP) of 25.2 ± 2.3 mm Hg. Following six months of treatment no statistical difference existed for the mean 24–hour pressure between treatments (P = 0.3). However, the dorzolamide/timolol fixed combination group showed superior IOP reduction at 10:00 (–0.8 mm Hg, P = 0.01) and at 22:00 (–1.1 mm Hg, P < 0.0001). No differences between groups were observed at the other time points (P > 0.05) as well as maximum and minimum and the diurnal range of the IOP (P > 0.05). Regarding adverse events, the dorzolamide/timolol fixed combination group had more burning and stinging (P < 0.001) and bitter taste (P = 0.01), whereas the latanoprost group had more hypertrichosis (P = 0.02).
Conclusions:
Although the dorzolamide/timolol fixed combination and latanoprost had a similar 24–hour IOP lowering efficacy, the fixed combination may be more efficacious at individual time points in the morning and evening in patients with primary open–angle glaucoma or ocular hypertension.
Keywords: clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • intraocular pressure