Comparison of once- or twice-daily bimatoprost with twice-daily timolol inpatients with elevated IOP - A 3-month clinical trial

Objective: To compare the safety, tolerability, and efficacy of bimatoprost 0.03% instilled once daily or twice daily with timolol 0.5% twice daily. Design: Multicenter, 3-month, randomized, double-masked, interventional com parison trial. Participants: Patients diagnosed with ocular hypertension or glaucoma (n = 596). Intervention: Patients received bimatoprost 0.03% ophthalmic solution once daily (8 PM, With vehicle control at 8 AM), bimatoprost 0.03% twice daily ( 8 AM; 8 PM), or timolol 0.5% twice daily (8 AM; 8 PM) in an uneven 2:2:1 ra ndomization. Scheduled visits were at prestudy, baseline (day 0), weeks 2 a nd 6, and month 3. Intraocular pressure (IOP) was measured at 8 AM (predose ), 10 AM, and 4 PM. Main Outcome Measures: The primary outcome measure was reduction in IOP in the eye with higher IOP at baseline. Secondary outcome measures included sa fety variables (adverse events, ophthalmoscopy, biomicroscopy, iris pigment ation, laser-flare meter, visual acuity, visual fields, heart rate, blood p ressure, blood chemistry, hematology, and urinalysis). Results: At month 3, the mean reduction in IOP from baseline at 8 AM was 9. 16 mmHg (35.2%) with bimatoprost once daily, 7.78 mmHg (30.4%) with bimatop rost twice daily, and 6.74 mmHg (26.2%) with timolol twice daily. At all fo llow-up visits, mean IOP reductions were significantly greater in the bimat oprost once daily group than in the timolol group at each time point (8 AM, 10 AM, and 4 PM; P < 0.001). Twice-daily dosing of bimatoprost also provid ed significantly greater mean reductions in IOP than timolol at most time p oints but was not as effective as once-daily dosing. Bimatoprost was associ ated with significantly more hyperemia and eyelash growth than timolol, whe reas timolol was associated with significantly more burning and stinging se nsation in eyes. Overall, bimatoprost was well tolerated with few discontin uations because of adverse events. Conclusions: Bimatoprost 0.03% once daily was safe and statistically superi or to timolol 0.5% twice daily in lowering IOP in patients with ocular hype rtension or glaucoma. Bimatoprost given once daily consistently provided IO P reductions approximately 2 to 3 mmHg greater than those provided by timol ol. Once-daily dosing of bimatoprost, 0.03%, demonstrated greater IOP-lower ing effect and better ocular tolerability than twice-daily dosing. Ophthalm ology 2001;108: 1023-1032 (C) 2001 by the American Academy of Ophthalmology .