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Published on: March 12, 2016
Efficacy of Timolol 0.1% Gel and a Prostaglandin Analog in an Unfixed Combination Compared to the Corresponding Fixed
Carlo Nucci1, Chiara Varesi1, Alessio Martucci1
1Ophthalmology Unit, Department of Exp. Medicine and Surgery, University of Rome Tor Vergata, Rome - Italy.
Purpose:
To investigate the intraocular pressure (IOP) reduction with prostaglandin analogs (PGAs)-timolol fixed combinations versus the unfixed combination of the same PGAs and timolol 0.1% in gel-forming carbomer.
Methods:
Patients with primary open-angle glaucoma (POAG) receiving for at least 4 weeks the fixed combinations of PGA-timolol, administered once a day in the evening (0.005% latanoprost with 0.5% timolol, 0.004% travoprost with 0.5% timolol, 0.03% bimatoprost with 0.5% timolol) were switched to an unfixed combination of the same PGA (once a day in the evening) with timolol 0.1% in gel-forming carbomer (once a day in the morning) for at least 4 weeks. The primary endpoint was to compare efficacy of fixed vs unfixed combinations in lowering IOP. The effects of both regimens on short-term IOP fluctuations were also assessed.
Results:
A total of 32 patients (64 eyes) fulfilled inclusion criteria: 17 patients received latanoprost-timolol fixed combination, 9 travoprost-timolol fixed combination, 6 bimatoprost-timolol fixed combination. For all considered time periods each unfixed combination induced an IOP reduction significantly higher than the corresponding fixed combination (paired t test: p<0.05 in all measurements). The diurnal IOP reduction was significantly higher during the unfixed combinations (p<0.001). Unfixed combinations significantly decreased IOP diurnal fluctuations and increased the percentage of patients with daily IOP fluctuation ≤2 mm Hg.
Conclusions:
In this pilot study, PGA and timolol seems to be more effective in POAG treatment when administered as unfixed combinations, reducing both IOP and daily fluctuations. The once a day timolol 0.1% gel-forming carbomer may be a valuable option in PGA-timolol unfixed combination regimen.
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