Unoprostone as adjunctive therapy to timolol: a double masked randomised study versus brimonidine and dorzolamide

To compare the safety and efficacy of unoprostone, brimonidine, and dorzolamide as adjunctive therapy to timolol in patients with primary open angle glaucoma or ocular hypertension.

This was a randomised, double masked, parallel group, multicentre (14) study. After using timolol maleate 0.5% monotherapy twice a day for 2 weeks, patients (n = 146) with an early morning intraocular pressure (IOP) between 22 and 28 mm Hg, inclusively, received unoprostone isopropyl 0.15% (n = 50), brimonidine tartrate 0.2% (n = 48), or dorzolamide hydrochloride 2.0% (n = 48) twice daily as adjunctive therapy to timolol maleate 0.5% for another 12 weeks. Safety was based on comprehensive ophthalmic examinations, adverse events, and vital signs. Efficacy was based on mean change from baseline in the 8 hour diurnal IOP at week 12. Baseline was defined as values obtained after 2 weeks of timolol monotherapy.

Each drug was safe and well tolerated. Burning/stinging was the most common treatment emergent adverse event. No clinically relevant changes from baseline were observed for any ophthalmic examination or vital signs. At week 12, each adjunctive therapy produced statistically significant (p<0.001) reductions from timolol treated baseline in the mean 8 hour diurnal IOP (-2.7 mm Hg, unoprostone; -2.8 mm Hg, brimonidine; -3.1 mm Hg, dorzolamide). The extent of IOP reduction did not differ significantly between unoprostone and either brimonidine (p = 0.154) or dorzolamide (p = 0.101).

Unoprostone was safe and well tolerated and provided a clinically and statistically significant additional reduction in IOP when added to stable monotherapy with timolol. Furthermore, unoprostone was not significantly different from brimonidine and dorzolamide as adjunctive therapy to timolol.