Update and optimal use of a brinzolamide-timolol fixed combination in open-angle glaucoma and ocular hypertension

A comparative study on the efficacy of brinzolamide/timolol versus brinzolamide/brimonidine fixed drug combinations in primary open-angle glaucoma

Background

To compare the efficacy of brinzolamide 1%/timolol 0.5% fixed drug combination (BTFC) with brinzolamide 1%/brimonidine 0.2% fixed drug combination (BBFC) among the patients with primary open-angle glaucoma (POAG).

Results

The treatment with BTFC in the Group A subjects showed a significant decrease in the intraocular pressure (p = 0.0355*) and a significant increase in the central corneal thickness (p = 0.0087*). Similarly, in the Group B subjects, the treatment with BBFC showed a significant decrease in the intraocular pressure (p = 0.0327*) and a significant increase in the central corneal thickness (p = 0.0227*). In the process of comparing both the fixed drug combinations, there was no significant difference observed in the aspect of efficacy between both the groups in the decrease of intraocular pressure (p = 0.7100) and in the increase of central corneal thickness (p = 0.4077).

Conclusion

Both the fixed drug combinations almost showed a similar efficacy in treating the respective groups, and there is no significant difference observed in the aspect of efficacy between both the fixed drug combinations in decreasing the intraocular pressure and in increasing the central corneal thickness.

Intraocular pressure-lowering effects of commonly used fixed combination drugs with timolol in the management of primary open angle glaucoma

AIM

To evaluate intraocular pressure (IOP)-lowering effect and ocular tolerability of brimonidine/timolol, dorzolamide/timolol and latanoprost/timolol fixed combination therapies in the management of primary open angle glaucoma.

METHODS

Each drug was administered for two months, after which a circadian tonometric curve was recorded using a Goldmann applanation tonometer. Ocular discomfort (conjunctival hyperemia, burning or stinging, foreign body sensation, itching, ocular pain) of each eye was assessed by the subject on a standardized ocular discomfort scale.

RESULTS

Among the three study groups, there were no significant differences in the mean baseline IOP measurements, mean 2(nd) mo IOP measurements, and mean (%) change of IOPs from baseline. Among the three study groups, there were no significant differences in the mean IOP measurements obtained at circadian tonometric curves at baseline and at two months controls. In sum brimonidine/timolol, dorzolamide/timolol and latanoprost/timolol fixed combination therapies showed similar effects on IOP levels.

CONCLUSION

Brimonidine/timolol, dorzolamide/timolol and latanoprost/timolol fixed combination therapies showed similar lowering efficaties on IOP levels whereas there was no any difference between each other.

Effect of 3 years of treatment with a dorzolamide/timolol (1%/0.5%) combination on intraocular pressure

Purpose

We aimed to evaluate the effect on the intraocular pressure (IOP) of a dorzolamide/timolol (1%/0.5%) fixed combination (DTFC) ophthalmic agent for 3 years.

Participants

A total of 19 consecutive patients who had previously been treated with mono-therapy or any combination of a beta-blocker, carbonic anhydrase inhibitor, or prostaglandin analog, for primary open-angle glaucoma (POAG) (n=5) or normal tension glaucoma (N=14) were enrolled.

Methods

Patients were switched to DTFC from their prior glaucoma therapy. The IOP was measured at intervals of 4–6 weeks for 3 years. Treatment failure was defined as an increase of IOP by ≥10% from baseline after switching to DTFC.

Results

The average IOP decreased significantly from 14.1±2.9 mmHg at baseline to 12.2±2.2, 11.8±2.4, 12.1±2.5, 11.6±1.8, and 12.1±2.7 mmHg at 3, 6, 12, 24, and 36 months, respectively, after switching therapy (all P<0.05). The mean percent decrease of IOP was 12.0%±13.0%, 14.5%±14.2%, 12.2%±18.7%, 16.0%±12.8%, and 12.8%±15.2% at 3, 6, 12, 24, and 36 months, respectively, after switching. Univariate or multivariate analysis revealed the percent decrease of IOP was associated with the type of glaucoma (POAG) at 3 and 12 months, and with the baseline IOP at 3, 12, 24, and 36 months. Kaplan–Meier analysis demonstrated that the percentage of patients who remained on treatment with DTFC was 94.7%, 94.7%, 84.2%, 78.9%, and 78.9% at 3, 6, 12, 24, and 36 months, respectively. Cox proportional hazards analysis showed that the type of glaucoma (POAG) was associated with an increased risk of failure to control the IOP.

Conclusion

The IOP-lowering effect of DTFC was demonstrated for 3 years in this study. The baseline IOP had an important influence on the reduction of IOP achieved by DTFC.

Effect of dorzolamide/timolol combination on the visual field in glaucoma

PURPOSE

To evaluate the effect of treatment for 3 years with a dorzolamide/timolol (1%/0.5%) fixed combination (DTFC) on visual field progression in patients with open-angle glaucoma.

PARTICIPANTS

A total of 14 consecutive patients were enrolled who had been previously treated with monotherapy or any combination of a beta blocker, carbonic anhydrase inhibitor, and/or prostaglandin analog for primary open-angle glaucoma (POAG; n=4) or normal-tension glaucoma (NTG; n=10).

METHODS

Patients were switched to DTFC from their prior glaucoma therapy. The IOP was measured at intervals of 4-6 weeks, and the visual fields were examined at least twice a year for 3 years. The annual change of mean deviation (MD slope) was used to quantify visual field loss.

RESULTS

The mean MD value was -5.9±5.0 dB at baseline; it was -5.6±4.8 dB at 12 months, -5.9±5.0 dB at 24 months, and -5.6±5.1 dB at 36 months after switching. The mean MD slope was -0.2±0.8 dB/year before switching and 0.3±1.3 dB/year from baseline to 1 year, -0.3±1.1 dB/year from 1-2 years, and 0.3±0.9 dB/year from 2-3 years after switching. The mean MD slope from baseline to 36 months was correlated with the IOP reduction rate at 36 months after switching. Visual field progression was associated with the IOP reduction rate at 12 months after switching.

CONCLUSION

Switching to DTFC from prior glaucoma therapy improved the MD slope for at least 3 years. Reduction of the IOP after switching to DTFC was effective for delaying visual field progression. Although our study was not nonrandomized and was small in scale, the findings suggest that DTFC might have a beneficial effect on the visual fields in patients with open-angle glaucoma.

Formulation and evaluation of stimuli-sensitive hydrogels of timolol maleate and brimonidine tartrate for the treatment of glaucoma

Background:

Stimuli-sensitive hydrogels are hydrophilic, three-dimensional, polymeric network structure capable of imbibing large amounts of water or biological fluids on stimulation, such as pH, temperature, and ionic change. Owing to the drawback of conventional therapy for ocular delivery, and to provide additive effect on intraocular pressure (IOP) reduction, stimuli sensitive hydrogel membranes containing a combination of timolol maleate and brimonidine tartrate were formulated for the treatment of glaucoma.

Materials and Methods:

Stimuli-sensitive hydrogel were formulated by timolol maleate and brimonidine tartrate. Poly acrylic acid (carbopol C 934p) is used as a gelling agent, hydroxylpropyl methylcellulose as viscolizer, sodium chloride as tonicity agent. Bezalkonium chloride as preservative. White rabbits of both sexes, weighing between 2 and 3 kg were used for the study. Stirring of ingredients in pH 4 phosphate buffers at high speed was carried out.

Result:

Viscosity of the prepared hydrogels lies in the optimum range that is, 25-55 cps. Infrared spectroscopy studies show that there is no interaction between the drug and polymer. Drug released up to 90% at the end of 8 h. The hydrogel membranes were found to be sterile, nonirritant to the eye. Marketed formulation showed a decrease in IOP up to 14 mmHg at the end of 5 h and then elimination of drug, F2 and F6 maintain the sustained effect up to 12 h.

Conclusion:

Stimuli-sensitive hydrogels was successfully formulated and evaluated for rheological studies, drug release studies, drug interaction studies, sterility studies, ocular irritation studies, and in vivo studies. IOP lowering activity of the combination of timolol maleate and brimonidine tartrate in stimuli-sensitive hydrogel was better when compared with alone medication, which shows the additive effect of combination medication.

Six-month results from a Phase III randomized trial of fixed-combination brinzolamide 1% + brimonidine 0.2% versus brinzolamide or brimonidine monotherapy in glaucoma or ocular hypertension

Background

The objective of this study was to examine the safety and intraocular pressure (IOP)-lowering efficacy of a fixed combination of brinzolamide 1% + brimonidine 0.2% (BBFC) after six months of treatment in patients with open-angle glaucoma or ocular hypertension.

Methods

This was a randomized, multicenter, double-masked, three-month, three-arm contribution-of-elements study with a three-month safety extension. Patients were randomly assigned 1:1:1 to treatment with BBFC, brinzolamide 1%, or brimonidine 0.2% after a washout period. Patients dosed their study medications three times daily at 8 am, 3 pm, and 10 pm for six months. Patients returned for visits at two weeks, six weeks, three months, and six months. IOP measurements were used to assess efficacy. Safety assessments were adverse events, corrected distance visual acuity, slit-lamp biomicroscopy, pachymetry, perimetry, fundus parameters, and cardiac parameters.

Results

A total of 690 patients were randomized. Six-month mean IOP values were similar to those at three months, when the mean IOP in patients treated with BBFC was significantly lower than that of either monotherapy group. A total of 175 patients experienced at least one treatment-related adverse event (BBFC, 33.0%; brinzolamide, 18.8%; brimonidine, 24.7%), eight of which were severe, and five resulted in discontinuation. Seventy-seven patients discontinued participation due to treatment-related adverse events (BBFC, 17.2%; brinzolamide, 2.1%; brimonidine, 14.5%). There were 21 serious adverse events (n = 7 in each group), none of which was related to treatment. Resting mean pulse and blood pressure with BBFC were similar to those with brimonidine, demonstrating modest, clinically insignificant decreases. No new or increased risks were identified with use of BBFC relative to either monotherapy.

Conclusion

This study showed that, after six months of treatment, the safety profile of BBFC was similar to that of its individual components and its IOP-lowering activity was similar to its efficacy at three months, when it was superior to both brinzolamide 1% alone and brimonidine 0.2% alone.

Preference for a fixed combination of brinzolamide/timolol versus dorzolamide/timolol among patients with open-angle glaucoma or ocular hypertension

Objective

To assess ocular discomfort upon instillation and patient preference for brinzolamide/timolol relative to dorzolamide/timolol, in patients with open-angle glaucoma or ocular hypertension.

Methods

This was a multicenter, prospective, patient-masked, randomized, crossover study. On day 0, patients received one drop of brinzolamide/timolol in one eye and one drop of dorzolamide/timolol in the contralateral eye. On day 1, patients were randomly assigned to receive one drop of either brinzolamide/timolol or dorzolamide/timolol in both eyes; on day 2, patients received one drop of the alternate treatment in both eyes. Measures included a patient preference question on day 2 (primary) and mean ocular discomfort scale scores on days 1 and 2 (secondary). Safety assessments included adverse events, visual acuity, and slit-lamp examinations.

Results

Of 120 patients who enrolled, 115 completed the study. Of these, 112 patients instilled both medications and expressed a study medication preference on day 2. A significantly greater percentage preferred brinzolamide/timolol to dorzolamide/timolol (67.0% versus 30.4%; P < 0.001). The ocular discomfort (expressed as mean [standard deviation]) with brinzolamide/timolol was significantly lower than with dorzolamide/timolol (day 2:1.9 [2.3] versus 3.7 [2.8], respectively [P = 0.0003]; both days combined: 2.1 [2.5] versus 3.5 [2.9], respectively [P = 0.00014]). On day 1, five patients receiving brinzolamide/timolol reported five nonserious adverse events (AEs): flu (n = 1), bitter taste (n = 2), and headache (n = 2). Four events, bitter taste (two events) and headache (two events), were considered related to brinzolamide/timolol. Events were mild in intensity, except bitter taste of moderate intensity reported by one patient. No AEs were reported at day 2. All AEs resolved without additional treatment. No clinically relevant changes from baseline were observed in best-corrected visual acuity or slit-lamp examinations of ocular signs.

Conclusion

Patients had less discomfort with brinzolamide/timolol than with dorzolamide/timolol, and more expressed a preference for brinzolamide/timolol. Both treatments were generally safe and well tolerated.