0.05%, 0.1% and 0.25% Verosudil (AR-12286) ophthalmic solutions in patients diagnosed with ocular hypertension or glaucoma. All 3 concentrations of AR-12286 produced statistically and clinically significant reductions in mean IOP that were dose dependent, with peak effects occurring 2 to 4 hours after dosing. Mean IOP at peak effect ranged from 17.6 to 18.7 mm Hg (-6.8 to -4.4 mm Hg) for the 3 concentrations. The largest IOP reductions were produced by 0.25% AR-12286 after twice daily dosing (up to -6.8 mm Hg; 28%). The 0.25% concentration dosed once-daily in the evening produced highly significant IOP reductions throughout the following day (-5.4 to -4.2 mm Hg).