A comparison of once-daily morning vs evening dosing of concomitant latanoprost/timolol

To evaluate morning vs evening once daily concomitant latanoprost 0.005%/timolol maleate 0.5% therapy in ocular hypertensive or primary open-angle glaucoma patients.

Prospective single-center double-masked crossover comparison.

Patients who responded to timolol maleate 0.5% given twice daily were randomized to either evening or morning dosing of concomitant latanoprost 0.005% and timolol maleate 0.5% therapy for 7 weeks. Twenty-four hour diurnal curve intraocular pressure (IOP) testing was performed following each period.

Thirty-six patients completed this study. There was a significant reduction at each time point in the 24-hour diurnal curve of both evening (17.1 +/- 2.7 mm Hg) and morning (17.3 +/- 3.1 mm Hg) dosed latanoprost/timolol maleate compared with timolol maleate given twice daily (21.1 +/- 3.3 mm Hg) (P <.0001). When the morning and evening dosing groups were compared directly, the 06:00 time point was statistically lower with evening dosing (16.4 +/- 2.3 mm Hg) vs morning dosing (17.9 +/- 2.8 mm Hg) (P =.01). Overall, a trend existed for greater daytime reduction with night-time dosing of the concomitant therapy, whereas morning dosing tended to give lower night-time pressures. There was a significantly lower mean range of diurnal pressure with evening (3.6 mm Hg) vs morning (4.3 mm Hg) dosing (P =.02). No differences in adverse events existed between the treated arms.

This study suggests that latanoprost and timolol maleate, both given once daily in the morning or evening, effectively reduce the IOP for the 24-hour diurnal curve when compared with timolol maleate twice daily.