Additive intraocular pressure reduction effect of fixed combination of maleate timolol 0.5%/dorzolamide 2% (Cosopt) on monotherapy with latanoprost (Xalatan) in patients with elevated intraocular pressure: a prospective, 4-week, open-label, randomized, controlled clinical trial.
OBJECTIVE
To evaluate the additive effect of dorzolamide/timolol fixed combination in patients under monotherapy with latanoprost.


METHODS
In this prospective, 4-week, randomized, open-label controlled clinical trial, patients with open-angle glaucoma or ocular hypertension, which presented at least 15% intraocular pressure (IOP) reduction after a minimum period of 15 days of monotherapy with latanoprost and whose IOP level was considered above the established target-IOP level were randomized to receive fixed combination of timolol/dorzolamide twice daily in one of eyes. The fellow eye was kept under monotherapy and was included in the control group. A modified diurnal tension curve (mDTC) followed by the water drinking test were performed in the baseline and week 4 visits to evaluate IOP profile between groups.


RESULTS
Forty-nine per-protocol patients were analyzed. After latanoprost monotherapy run-in period, IOP levels were significantly reduced (P<0.001) in both control and study groups to 15.34+/-2.96 mm Hg and 15.24+/-2.84 mm Hg (30.8% and 32.2% IOP reduction, respectively; P=0.552). At week 4, mean baseline diurnal IOP levels were 15.60+/-3.09 and 14.44+/-3.03 (7.4% difference; P=0.01). Mean baseline IOP modified diurnal tension curve peak after latanoprost run-in period were 17.47+/-3.68 mm Hg and 17.02+/-3.35 mm Hg (control and study eyes, respectively; P=0.530). At week 4 visit, mean water-drinking test peaks were significantly reduced in the study eye group in comparison with the control group: 19.02+/-3.81 mm Hg and 20.39+/-4.19 mm Hg, respectively (6.7% reduction; P=0.039).


CONCLUSIONS
In our sample, dorzolamide 2%/timolol 0.5% fixed combination as add-on therapy in patients with open-angle glaucoma or ocular hypertension under monotherapy with latanoprost with IOP already in mid-teens levels may further enhance pressure reduction.
Hatanaka
Marcelo
M
Department of Ophthalmology, School of Medicine, University of Sao Paulo, Brazil. info@centroavancado.net
Reis
Alexandre
A
Sano
Milena Eimi
ME
Susanna
Remo
R
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000008:administration & dosage*; D004338:Drug Combinations; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis / Q000188:drug therapy*; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects*; D000077338:Latanoprost; D008297:Male; D008875:Middle Aged; D009798:Ocular Hypertension / Q000175:diagnosis / Q000188:drug therapy; D011446:Prospective Studies; D011461:Prostaglandins F, Synthetic / Q000008:administration & dosage*; D013449:Sulfonamides / Q000008:administration & dosage*; D013876:Thiophenes / Q000008:administration & dosage*; D013997:Time Factors; D013999:Timolol / Q000008:administration & dosage*; D014065:Tonometry, Ocular; D016896:Treatment Outcome; D014792:Visual Acuity
D000959:Antihypertensive Agents; D004338:Drug Combinations; D011461:Prostaglandins F, Synthetic; D013449:Sulfonamides; D013876:Thiophenes; C479140:dorzolamide-timolol combination; D000077338:Latanoprost; D013999:Timolol