PURPOSE: To compare the efficacy and safety of timolol hemihydrate 0.5% (Be
timol, Ciba Vision Ophthalmics, Duluth, Georgia) vs timolol maleate gel-for
ming solution 0.5% (Timoptic-XE, Merck, Blue Bell, Pennsylvania), both give
n every morning added to latanoprost 0.005% given every evening.
METHODS: A multicenter, randomized, crossover comparison was performed in p
atients with primary open-angle glaucoma or ocular hypertension. After at l
east a 4-week run-in period with latanoprost 0.005% (Xalatan, Pharmacia & U
pjohn, Kalamazoo, Michigan), both eyes from 30 patients (60 eyes) were rand
omly assigned to one of the two adjunctive therapies, timolol hemihydrate o
r timolol maleate gel for 6 weeks. At the end of the first period, the stud
y medicine was discontinued for a 2-week washout period. Patients then rece
ived the opposite medication for the second 6-week period. This study had a
n 80% power to exclude a 1-mm Hg difference between groups.
RESULTS: The baseline intraocular pressure after 1 month of latanoprost tre
atment only for all 30 subjects was 20.8 +/- 2.6 mm Hg. After 6 weeks of ti
molol hemihydrate, the 24-hour trough intraocular pressure was 17.5 +/- 3.4
mm Hg, and for timolol maleate gel, 17.9 +/- 3.5 mm Hg (P = .74). The peak
level 2 hours after dosing for timolol hemihydate was 16.4 +/- 2.6 mm Hg,
and for timolol maleate gel, 16.8 +/- 3.8 mm Hg (P = .84). No patient was d
iscontinued from the study be cause of lack of efficacy. No differences wer
e observed between treatments in visual acuity, anterior segment findings,
or adverse events.
CONCLUSIONS: Once-daily beta-blocker therapy is an effective ocular hypoten
sive adjunctive treatment 24 hours after dosing when added to latanoprost,
for which timolol hemihydrate 0.5% solution and timolol maleate gel 0.5% ap
pear equally effective and safe. (C) 1999 by Elsevier Science Inc. All righ
ts reserved.