A randomized, investigator-masked, 4-week study comparing timolol maleate 0.5%, brinzolamide 1%, and brimonidine tartrate 0.2% as adjunctive therapies to travoprost 0.004% in adults with primary open-angle glaucoma or ocular hypertension

Abstract

Objective: The objective of this study was to assess the hypotensive efficacy of timolol maleate 0.5%, brinzolamide 1%, or brimonidine tartrate 0.2% ophthalmic solution, administered in conjunction with travoprost 0.004%, in patients with primary open-angle laucoma (OAG) or ocular hypertension (OHT) whose intraocular pressure (IOP) did not meet the treatment target using travoprost 0.004% monotherapy. Methods: This was a randomized, comparative, investigator-masked study. Patients with OAG or OHT treated with travoprost 0.004% monotherapy were randomized to receive 1 of the 3 adjunctive therapies (timolol maleate 0.5%, brinzolamide 1%, or brimonidine tartrate 0.2%), 1 drop BID in each randomized eye, in addition to 1 drop QD of travoprost for a period of 4 weeks. IOP was measured on days 0 (travoprost 0.004%) and 28 (travoprost 0.004% and adjunctive treatment). Adverse events were monitored on days 0 and 28 by patient interview. Results: Twenty-nine patients with OAG (46 eyes) and 3 patients with OHT (6 eyes), with a total of 52 eligible eyes, completed the study; 28 eyes were from male patients and 24 were from female patients. In addition to continuing travoprost treatment, 20 eyes received timolol, 16 eyes received brinzolamide, and 16 eyes were treated with brimonidine. There were no significant differences among the groups in the mean (SD) IOP at baseline on day 0 (19.0 [4.1], 17.2 [3.5], and 17.0 [3.1] mm Hg, respectively; P = NS). On day 28, the reduction in mean (SD) IOP in eyes treated with brimonidine tartrate 0.2% was significantly smaller (2.3 [1.8] mm Hg vs 3.9 [1.8] mm Hg [ P = 0.01]) and the mean (SD) percentage reduction in IOP was significantly smaller (13.4% [9.1%] vs 20.2% [7.5%] [ P = 0.01]) when compared with timolol maleate 0.5%, and likewise when compared with brinzolamide 1% (4.0 [2.1] mm Hg [ P = 0.02] and 22.7% [8.6%] [ P = 0.006], respectively). The group treated with brinzolamide was associated with a similar reduction in IOP to timolol ( P = NS for both mean [SD] IOP and percentage reduction in IOP compared with timolol monotherapy). Barring the occasional conjunctival hyperemia, which was excluded as an adverse event for the purposes of this study, no adverse events were recorded. Conclusion: Brinzolamide 1% and timolol maleate 0.5% treatment were both associated with a significantly greater reduction in IOP compared with brimonidine 0.2% when administered as a nonfixed adjuvant to travoprost 0.004% in the treatment of patients with OAG and OHT whose IOP was inadequately controlled with travoprost monotherapy. All treatments were well tolerated.