Purpose: To evaluate bimatoprost versus latanoprost and timolol fixed combination (LTFC) over the 24-hour diurnal curve in patients who switched from timolol.
Methods: In this prospective, observer-masked, randomized clinical trial, 64 patients whose intraocular pressures (IOPs) were not effectively controlled with timolol were enrolled. At pretrial visit IOPs and central corneal thickness were measured. After the baseline visit, timolol was replaced by bimatoprost or LTFC. IOPs were recorded at 8 AM, noon, 4 PM, 8 PM, midnight, and 4 AM at baseline, week 8, and week 16 visits.
Results: At baseline and week 8 visits, there was no significant difference between the LTFC and bimatoprost group for the mean IOPs at 6 time points in 24 hours, the mean diurnal IOP, and range of diurnal IOP. At week 16, the mean IOP of the bimatoprost group (15.7±2 mm Hg) at 8 AM and 12 o' clock, midnight, was statistically significantly lower than that of the LTFC group (16.8±1.5 and 16.9±1.7 mm Hg; P=0.03 and 0.002). A statistically significant difference was not found between the proportions of patients who had 15% and 20% decrease in mean diurnal IOP and the mean daytime, nighttime, diurnal IOP reductions of the 2 study groups at weeks 8 and 16 (P>0.05). In the bimatoprost group punctate epitheliopathy, conjunctival hyperemia, and lid erythema were found to be more frequent.
Conclusions: The LTFC and bimatoprost therapies were equally effective in maintaining IOP at lower levels during the 24-hour period in patients who switched from timolol therapy. Adverse events were more frequent with bimatoprost therapy.