Considerations in glaucoma therapy: fixed combinations versus their component medications

Abstract

Fixed combinations of medications that lower intraocular pressure (IOP) are increasingly used in the treatment of glaucoma and ocular hypertension and offer several potential advantages over combined use of the separate component medications including enhanced convenience, improved adherence, reduced exposure to preservatives, and possible cost savings. This review aims to examine the current role of IOP-lowering fixed combinations in disease management. The results of studies that compared the efficacy and safety of IOP-lowering fixed combinations with their component medications are summarized, including those fixed combinations that consist of a prostaglandin analog and timolol. The fixed combinations currently available for use in the United States are fixed-combination dorzolamide/timolol (FCDT) and fixed-combination brimonidine/timolol (FCBT). Both of these fixed combinations reduce IOP more effectively than their component medications used separately as monotherapy. FCBT therapy also demonstrates a more favorable safety profile and reduced ocular allergy compared to monotherapy with brimonidine, a component medication. Few studies have directly compared the efficacy and safety of FCDT and FCBT, but available evidence suggests that FCBT is at least as effective as FCDT in lowering IOP and is more comfortable and better tolerated. Additional studies are needed to further evaluate the comparative efficacy and tolerability of FCDT and FCBT in the management of glaucoma and ocular hypertension.

Eficácia da combinação fixa de timolol 0,5% e brinzolamida 1% no tratamento do glaucoma primário de ângulo aberto e na hipertensão ocular

“…Cada vez mais as combinações fixas de medicações antiglaucomatosas têm ganhado espaço na prática clínica diária, por fornecerem maior potência na diminuição da PIO e também porque melhoram a aderência dos pacientes ao tratamento (8,9) . Com o surgimento de uma nova combinação no mercado, procuramos avaliar a eficácia e a tolerância dessa nova formulação com pacientes que não usavam nenhuma droga no tratamento do glaucoma.…”

Drops, Drops, and More Drops

“…This, in and of itself, can lead to a vicious cycle, because more complex regimens with multiple medications may present an even greater challenge to adherence. (Tsai, 2006;Higginbotham, 2010) Intermittent dosing will not lead to sustained lowering of IOP, and deterioration of the visual field may increase. If the patient presents at the next visit with an optimal IOP, but there is evidence of visual field progression, it is impossible to distinguish whether the target IOP needs to be lowered by adding therapy, or if the target IOP is appropriate and the progression is due to nonadherence.…”

“…Brimonidine, an alpha-adrenergic blocker, and dorzolamide, a carbonic anhydrase inhibitor, can be used as monotherapy and are also used as adjunctive therapy in fixed combinations with timolol. (Chan et al, 2007;Woodward and Chen, 2007;Higginbotham, 2010;Khouri et al, 2009) …”

Long-Term Outcomes of Prostaglandin Analog Versus Timolol Maleate in Ocular Hypertensive or Primary Open-Angle Glaucoma Patients in Europe

“…1,2 When target IOP is not achieved with a single agent, combined therapy using drugs with different mechanisms of action is recommended. 3 Multiple local therapies may be associated with more local and systemic side effects 4 because of increased exposure to preservatives, with a higher incidence of ocular signs and symptoms, and poor compliance. [5][6][7] Fixed combinations (FCs) of 2 antiglaucoma drugs have been formulated to obtain a greater reduction in IOP than that which can be achieved using single agents, allow fewer doses, and ensure less exposure to preservatives.…”

“…[5][6][7] Fixed combinations (FCs) of 2 antiglaucoma drugs have been formulated to obtain a greater reduction in IOP than that which can be achieved using single agents, allow fewer doses, and ensure less exposure to preservatives. 4 Combinations of b-blockers and prostaglandin analogs (PGAs) are frequently used in clinical practice because of their different, but complementary mechanisms of action. PGA FCs were introduced several years ago to improve adherence to chronic topical medical therapy in patients with OHT and OAG, [8][9][10] and currently include 0.005% latanoprost + 0.5% timolol, 0.004% travoprost + 0.5% timolol, and 0.003% bimatoprost + timolol 0.5%.…”