A Review of Additivity to Prostaglandin Analogs: Fixed and Unfixed Combinations

Fixed versus Unfixed Combination of Topical Latanoprost/Timolol for Glaucoma: An Observational Study Investigating the Level of Adherence and Ocular Surface Health

PURPOSE

To investigate the effect of fixed combination versus concomitant unfixed topical glaucoma treatment on patients' adherence and ocular surface health.

PATIENTS AND METHODS

This is a 6-month, prospective, parallel-group, observational study in patients with ocular hypertension (OHT), primary open-angle glaucoma (POAG), or exfoliation glaucoma (XFG). A total of 142 patients with similar baseline characteristics were enrolled in this study. Seventy-one patients received a Latanoprost 0.005%/Timolol 0.5% fixed combination in the evening, whereas seventy-one patients received the unfixed treatment with Latanoprost 0.005% in the evening and Timolol 0.5% twice daily. The primary outcome was the adherence rate at baseline, and at the 3- and 6-month follow-up visits. The secondary outcomes included the signs of ocular surface disease (OSD) and intraocular pressure (IOP).

RESULTS

The adherence of patients treated with the fixed combination was higher than the unfixed treatment at the 3-month (78.0% vs. 63.0%, p < 0.001) and at the 6-month visits (73.0% vs. 58.5%, p < 0.01). The Break-up Time, Schirmer test, and Van Bijsterveld score were worse in the unfixed group at baseline and all subsequent examinations (p < 0.05 for all comparisons). There were no differences in the mean IOP between groups at baseline, 1-, and 3-month visits. IOP appears higher in the unfixed group at 6 months (16.7 vs. 15.0 mmHg, p < 0.01).

CONCLUSION

The patients with ocular hypertension and primary open-angle glaucoma treated with a fixed combination are significantly more adherent and show a healthier ocular surface than those treated with an unfixed combination. The study provides significant evidence of the benefits of fixed combination treatment.

A comparison of country-level data from the VISIONARY study examining treatment outcomes with preservative-free tafluprost/timolol fixed-dose combination therapy

OBJECTIVE

Analysis and comparison of country-level data from the VISIONARY study, examining treatment outcomes with the topical fixed-dose combination of preservative-free tafluprost (0.0015%) and timolol (0.5%) (PF tafluprost/timolol FC) in adults with open-angle glaucoma (OAG) and ocular hypertension (OHT) who were insufficiently treated with or unable to tolerate either beta-blocker or prostaglandin analogue (PGA) topical monotherapy.

METHODS

A European, prospective, observational study was conducted in 11 countries. Adults with OAG/OHT were switched to the PF tafluprost/timolol FC from either PGA or beta-blocker topical monotherapy. Statistical analysis examined changes in mean standard deviation (SD) intraocular pressure (IOP) from baseline at Week 4, Week 12 and Month 6. Data were documented for each eye separately at baseline and during follow up visits, with the eye reported to have the higher IOP (mmHg), as measured using Goldmann applanation tonometry, being selected for analysis (study eye). Country-level subanalysis examined outcomes by prior monotherapy, diagnosis and timing of dosing for those countries recruiting ≥20 patients (Country-level Subanalysis Population). Two-sided paired t-test was used to assess significance regarding mean IOP reduction from baseline and a compound symmetry covariance model was used in cross-country comparisons regarding variation in IOP change from baseline. Treatment-related adverse events (AEs) were evaluated.

RESULTS

Mean (SD) age among patients recruited to the VISIONARY study ranged between 63.9 (11.8) and 72.4 (10.6) years across all countries. The majority of participants (>50%) were female in each country. The Country-level Subanalysis Population included 551 eyes. Mean (SD) IOP was significantly reduced from baseline in each country at Week 4, Week 12 and Month 6 (p < .0001). Mean IOP reduction at Month 6 ranged from 5.0 mmHg (22.6%, Hungary) to 7.8 mmHg (31.8%, Latvia) and varied significantly between countries (p < .001). The greatest reductions were in Latvia and Russia, where baseline IOP was highest. Country-level IOP reductions were significant irrespective of prior monotherapy, diagnosis or dosing time (p < .0001). Most treatment-related AEs occurred in the UK (26 events, 73% mild). One serious AE was reported (Russia, status asthmaticus). Tolerability with PF tafluprost/timolol FC therapy was rated as good/very good by most patients (85.7-100%) in all countries.

CONCLUSION

Subanalysis of VISIONARY study data revealed significant IOP reductions following a switch to the PF tafluprost/timolol FC from either PGA or beta-blocker topical monotherapy. Cross-country variation was likely due to baseline IOP differences. Within country, outcomes were consistent regardless of diagnosis, dosing or prior monotherapy. Treatment was generally well tolerated.

Treatment of Open-Angle Glaucoma and Ocular Hypertension with the Fixed-Dose Combination of Preservative-Free Tafluprost/Timolol: Clinical Outcomes from Ophthalmology Clinics in Italy

Introduction

The VISIONARY study examined the intraocular pressure (IOP)-lowering efficacy and tolerability of the preservative-free fixed-dose combination of tafluprost (0.0015%) and timolol (0.5%) (PF tafluprost/timolol FC) in a real-world setting. The country-level data reported herein comprise the largest and first observational study of PF tafluprost/timolol FC therapy in Italy.

Methods

An observational, multicenter, prospective study included adult Italian patients with open-angle glaucoma (OAG) or ocular hypertension (OHT) demonstrating insufficient response or poor tolerability with topical prostaglandin analogue (PGA) or beta-blocker monotherapy. Treatment was switched to PF tafluprost/timolol FC therapy at baseline. Primary endpoint was the absolute mean IOP change from baseline at Month 6. Exploratory and safety endpoints included change in IOP at Weeks 4 and 12, ocular signs, symptom severity and reporting of adverse events (AEs).

Results

Overall, 160 OAG/OHT patients were included. Mean ± standard deviation IOP was reduced from 19.6 ± 3.6 mmHg at baseline to 14.5 ± 2.6 mmHg at Month 6 (reduction of 5.1 ± 3.7 mmHg; 24.1%; p < 0.0001). IOP reduction was also statistically significant at Week 4 (23.1%; p < 0.0001) and Week 12 (24.7%; p < 0.0001). Based on data cutoff values for mean IOP change of ≥20%, ≥25%, ≥30% and ≥35%, respective Month 6 responder rates were 68.1%, 48.7%, 36.2% and 26.9%. Most ocular signs and symptoms were significantly reduced in severity from baseline at Month 6. Two non-serious and mild AEs were reported during the study period, among which, one AE was treatment-related (eyelash growth).  

Conclusion

Italian OAG and OHT patients demonstrated a significant IOP reduction from baseline at Week 4 that was maintained over a 6-month period following a switch from topical PGA or beta-blocker monotherapy to PF tafluprost/timolol FC therapy. Severity of most ocular signs and symptoms was significantly reduced during the study period, and PF tafluprost/timolol FC was generally well tolerated.

Green HPLC method with time programming for the determination of the co-formulated eye drops of tafluprost and timolol in their challengeable ratio

A new, simple and selective HPLC method was implemented for the simultaneous estimation of tafluprost (TFL) and timolol (TIM) in their new anti-glaucoma combination in the challengeable ratio of 3 and 1000 for TFL and TIM, respectively. Separation was achieved using a BDS Hypersil phenyl column and a mobile phase made up of acetonitrile: 0.015 M phosphate buffer (50:50 v/v, pH 3.5) delivered at 1 mL min⁻¹ and the separation was completed in less than 6 min. UV detection was time programmed at 220 nm for the first 4.5 min and later at 254 nm. Mebeverine (MEB) was used as an internal standard (I.S.). The linearity was observed in the ranges of 0.6–45 and 50–2000 µg mL⁻¹ with limits of detection (LOD) of 0.18, 16.48 µg mL⁻¹ and limits of quantification (LOQ) of 0.55, 49.94 µg mL⁻¹ for TFL and TIM, respectively. The method satisfied International Council for Harmonization (ICH) validation guidelines. The study was extended to the estimation of the studied drugs in their co-formulated eye drops as well as in their single dosage forms with acceptable percentage recoveries. Moreover, Green Analytical Procedure Index (GAPI) and analytical Eco-scale were investigated to confirm the greenness of the proposed HPLC method.

Treatment of Open-Angle Glaucoma and Ocular Hypertension with Preservative-Free Tafluprost/Timolol Fixed-Dose Combination Therapy: Results from the VISIONARY Study Population in Spain

Purpose: Data are presented from ophthalmology clinics in Spain participating in the VISIONARY study, examining the effectiveness, tolerability, and safety of the preservative-free tafluprost (0.0015%) and timolol (0.5%) fixed-dose combination (PF tafluprost/timolol FC) in the treatment of OAG and OHT. Methods: An observational, multicenter prospective study examined treatment outcomes following a switch to PF tafluprost/timolol FC in adult OAG/OHT patients demonstrating insufficient response to beta-blocker or prostaglandin analog (PGA) monotherapy. Primary end point was mean change in intraocular pressure (IOP) from baseline at month 6. Changes in the severity of ocular signs and symptoms were also assessed. Results: Overall, 92 patients (51.1% female) were included. Mean (standard deviation) age was 68.3 (12.1) years. Mean IOP was reduced from 21.9 mmHg at baseline to 16.7 mmHg at month 6 (22.3% decrease; P < 0.0001). Significant IOP reductions were observed at weeks 4 and 12 (P < 0.0001). Baseline PGA and beta-blocker users demonstrated mean month 6 IOP reductions of 5.5 mmHg (23.5%; P < 0.001) and 3.5 mmHg (14.6%; P = 0.029), respectively. Severity of conjunctival hyperemia, dry eye, irritation, itching, foreign body sensation, and eye pain was significantly reduced. Three treatment-related adverse events were reported, all were nonserious and mild/moderate in severity. Conclusion: In real-world clinical practice, PF tafluprost/timolol FC treatment provided significant IOP reductions over 6 months and was well tolerated among OAG/OHT patients showing poor response to PGA or beta-blocker monotherapy. IOP-lowering efficacy and improvements in ocular signs and symptoms were evident from week 4 and maintained over the 6-month study period. Trial Registration: European Union electronic Register of Post-Authorisation Studies (EU PAS) register number EUPAS22204.

Switching to Preservative-Free Tafluprost/Timolol Fixed-Dose Combination in the Treatment of Open-Angle Glaucoma or Ocular Hypertension: Subanalysis of Data from the VISIONARY Study According to Baseline Monotherapy Treatment

INTRODUCTION

The VISIONARY study demonstrated statistically significant intraocular pressure (IOP) reductions with the preservative-free fixed-dose combination of tafluprost 0.0015% and timolol 0.5% (PF tafluprost/timolol FC) in open-angle glaucoma (OAG) or ocular hypertension (OHT) patients, sub-optimally controlled with topical prostaglandin analogue (PGA) or beta-blocker monotherapy. Current subanalyses have examined these data according to the baseline monotherapy.

METHODS

A European, prospective, observational study included adults (aged ≥ 18 years) with OAG or OHT, who were switched to the PF tafluprost/timolol FC from PGA or beta-blocker monotherapy. Treatment outcomes were reported according to prior monotherapy subgroup: beta-blocker, preserved latanoprost, PF-latanoprost, bimatoprost, tafluprost, and travoprost. Endpoints included the mean change from baseline regarding IOP, conjunctival hyperemia, and corneal fluorescein staining (CFS) at Week 4 and Week 12, and at Month 6.

RESULTS

The subanalysis included 577 patients. All prior monotherapy subgroups demonstrated statistically significant IOP reductions from baseline at Week 4, that were maintained through Month 6 (p < 0.001). Mean (SD) IOP change at Month 6 was 6.6 (4.16), 6.3 (4.39), 5.6 (3.67), 4.9 (2.97), 4.6 (4.39), and 4.7  (3.64) mmHg for prior beta-blocker, preserved latanoprost, PF-latanoprost, tafluprost, bimatoprost, and travoprost subgroups, respectively. The largest IOP change was observed in the preserved latanoprost subgroup for each of the ≥ 20%, ≥ 25%, ≥ 30%, and ≥ 35% IOP reduction categories at Month 6, demonstrating respective reductions of 8.06, 9.20, 10.64, and 11.55 mmHg. CFS was significantly reduced at Month 6 in the prior bimatoprost subgroup (p = 0.0013). Conjunctival hyperemia severity was significantly reduced at each study visit for prior preserved latanoprost users (p < 0.001).

CONCLUSION

PF tafluprost/timolol FC therapy provided statistically and clinically significant IOP reductions from Week 4 over the total 6-month period, in patients with OAG/OHT, regardless of the type of prior PGA or beta-blocker monotherapy used. Conjunctival hyperemia severity and CFS decreased significantly in prior bimatoprost and preserved latanoprost users, respectively.

CLINICAL STUDY NUMBER

European Union electronic Register of Post-Authorization Studies (EU PAS) register number: EUPAS22204.

Aqueous outflow channels and its lymphatic association: A review

The human eye has a unique immune architecture and behavior. While the conjunctiva is known to have a well-defined lymphatic drainage system, the cornea, sclera, and uveal tissues were historically considered "alymphatic" and thought to be immune privileged. The very fact that the aqueous outflow channels carry a clear fluid (aqueous humor) along the outflow pathway makes it hard to ignore its lymphatic-like characteristics. The development of novel lymphatic lineage markers and expression of these markers in aqueous outflow channels and improved imaging capabilities has sparked a renewed interest in the study of ocular lymphatics. Ophthalmic lymphatic research has had a directional shift over the last decade, offering an exciting new physiological platform that needs further in-depth understanding. The evidence of a presence of distinct lymphatic channels in the human ciliary body is gaining significant traction. The uveolymphatic pathway is an alternative new route for aqueous outflow and adds a new dimension to pathophysiology and management of glaucoma. Developing novel animal models, markers, and non-invasive imaging tools to delineate the core anatomical structure and physiological functions may help pave some crucial pathways to understand disease pathophysiology and help develop novel targeted therapeutic approaches for glaucoma.

Intraocular Pressure Following Prerandomization Glaucoma Medication Washout in the HORIZON and COMPASS Trials

PURPOSE

To assess the effectiveness of topical ocular hypotensive medications in patients with open-angle glaucoma and to identify factors associated with postwashout intraocular pressure (IOP) elevation.

DESIGN

Secondary analysis of prerandomization data from 2 prospective, multicenter, randomized clinical trials.

METHODS

Fourteen hundred subjects (1,400 eyes, 781 from the HORIZON study of the Hydrus micro-stent and 619 from the COMPASS study of the Cypass micro-stent) with primary open-angle glaucoma who were using 0-4 classes of topical IOP-lowering medication underwent Goldmann applanation tonometry before and after a protocol-defined washout period.

RESULTS

The mean (standard deviation) age was 70.7 (8.0) years and 55.6% were female. The change in IOP following washout for patients using 0 (n = 100), 1 (n = 705), 2 (n = 355), 3 (n = 214), or 4 (n = 26) medications was 0.2 (2.8), 5.7 (3.3), 6.9 (3.7), 8.8 (5.0), and 9.5 (4.1) mm Hg, respectively (P < .001, Kruskal-Wallis test). Postwashout IOP change was similar between the HORIZON and COMPASS cohorts. No difference in postwashout IOP change was detected among individual prostaglandin analogues in patients on monotherapy. A generalized linear model identified the following factors to be associated with greater IOP rise upon medication washout: greater number of glaucoma medications, higher unmedicated IOP, thinner central corneal thickness (CCT), lack of prior selective laser trabeculoplasty (SLT), and male sex.

CONCLUSIONS

Cessation of glaucoma medications results in a dose-dependent IOP increase in treated open-angle glaucoma patients. Two independent clinical trial cohorts exhibit similar levels of IOP elevation upon washout, using standardized methodology to estimate real-world medication effectiveness. Thicker CCT and history of SLT may predict reduced response to IOP lowering medications.

Treatment of Open-Angle Glaucoma and Ocular Hypertension with Preservative-Free Tafluprost/Timolol Fixed-Dose Combination Therapy: The VISIONARY Study

Introduction

A non-interventional, multicenter, European, prospective evaluation of the effectiveness, tolerability, and safety of a topical preservative-free tafluprost (0.0015%) and timolol (0.5%) fixed-dose combination (PF tafluprost/timolol FC) in adults with open-angle glaucoma (OAG) and ocular hypertension (OHT) demonstrating insufficient response to topical beta-receptor blockers or prostaglandin analogue (PGA) monotherapy.

Methods

Mean intraocular pressure (IOP) change from baseline was measured at study visits following a switch to PF tafluprost/timolol FC. Primary endpoint was absolute mean IOP change at month 6. Change from baseline concerning ocular signs and symptoms was also explored.

Results

Analyses included 577 patients (59.6% female). Mean age (SD) was 67.8 (11.67) years. Mean (SD) IOP reduction from baseline was significant at all study visits; 5.4 (3.76) mmHg (23.7%) at week 4, 5.9 (3.90) mmHg (25.6%) at week 12, and 5.7 (4.11) mmHg (24.9%) at month 6 (p < 0.0001 for all visits). At month 6, 69.2%, 53.6%, 40.0%, and 25.8% were responders based on ≥ 20%, ≥ 25%, ≥ 30%, and ≥ 35% cutoff values for mean IOP, respectively. Significant reductions were observed concerning corneal fluorescein staining (p < 0.0001), dry eye symptoms, irritation, itching, and foreign body sensation (p < 0.001 for each parameter). Conjunctival hyperemia was significantly reduced at all study visits (p < 0.0001 at each visit). Overall, 69 treatment-related adverse events (AEs) were reported, one of which was serious (status asthmaticus). Most AEs were mild to moderate in severity, and the majority had resolved or were resolving at the end of the study period.

Conclusion

In clinical practice, PF tafluprost/timolol FC provided statistically and clinically significant IOP reductions in patients with OAG and OHT insufficiently controlled on or intolerant to PGA or beta-receptor blocker monotherapy. The full IOP reduction appeared at week 4 and was maintained over the 6-month study period. Key symptoms of ocular surface health improved.

Trial Registration

European Union electronic Register of Post-Authorisation Studies (EU PAS) register number, EUPAS22204.

Meibomian Gland Features and Conjunctival Goblet Cell Density in Glaucomatous Patients Controlled With Prostaglandin/Timolol Fixed Combinations: A Case Control, Cross-sectional Study

PURPOSE

To investigate, using in vivo confocal microscopy (IVCM), the Meibomian gland (MG) features and conjunctival goblet cell density (GCD) in glaucomatous patients controlled with prostaglandin/timolol fixed combinations (PTFCs).

MATERIALS AND METHODS

In this cross-sectional study, 60 white patients were treated with PTFCs, 15 with latanoprost+timolol (L+T) unfixed combination, and 15 controls were enrolled. Patients underwent the Ocular Surface Disease Index questionnaire, tear film breakup time, corneal staining, Schirmer test I, and IVCM of MGs and goblet cells. The main outcome measures were: mean Meibomian acinar density (MMAD) and area (MMAA), inhomogeneity of glandular interstice (InI) and acinar wall (InAW), and GCD.

RESULTS

PTFCs were: latanoprost/timolol (LTFC, 15 eyes), travoprost/timolol (TTFC, 15), bimatoprost/timolol (BTFC, 15), and preservative-free bimatoprost/timolol (PF-BTFC, 15) fixed combinations. Mean time on therapy did not differ among treatments. IVCM documented lower GCD, MMAD, and MMAA (P<0.001), and greater InI and InAW (P<0.05) in glaucoma patients compared with controls. L+T showed worse values compared with PTFCs and PF-BTFC (P<0.05). Preserved PTFCs showed lower MMAD, MMAA, GCD, and greater InI and InAW compared with PF-BTFC (P<0.05) and controls (P<0.001). Differences were not found among PTFCs. InI and InAW significantly correlated with Ocular Surface Disease Index and breakup time (P<0.001), corneal staining (P<0.05), and GCD (P<0.001); GCD correlated with MMAD (P<0.05).

CONCLUSIONS

PTFCs were less toxic towards MGs and goblet cells compared with the L+T unfixed combination, with PF-BTFC presenting the most tolerated profile. These findings should be carefully considered given the role of these structures in the induction of the glaucoma-related ocular surface disease.

The Diurnal and Nocturnal Effects of Pilocarpine on Intraocular Pressure in Patients Receiving Prostaglandin Analog Monotherapy

PURPOSE

The purpose of the study was to determine the 24-h effects of pilocarpine 2% ophthalmic solution on intraocular pressure (IOP) and ocular perfusion pressure (OPP) when used in addition to prostaglandin analog (PGA) therapy.

METHODS

Twenty-seven patients with ocular hypertension (OHTN) or open angle glaucoma who were receiving stable monotherapy with a PGA were admitted to an inpatient sleep laboratory for 24-h monitoring of IOP, blood pressure (BP), and heart rate over 2 separate visits. The first baseline visit was performed under PGA monotherapy only. During the second 24-h visit, pilocarpine 2% was administered four times daily in addition to their normal PGA dosing. For each study visit, measurements of all study metrics were performed every 2 h in the habitual position. OPP was calculated as 2/3[diastolic BP +1/3(systolic BP - diastolic BP)] - IOP.

RESULTS

During the diurnal period, pilocarpine significantly reduced IOP from a baseline of 18.2 ± 0.5 mmHg on PGA monotherapy to 17.1 ± 0.4 mmHg, P < 0.01. Similarly, pilocarpine significantly lowered IOP during the nocturnal period from 21.1 ± 0.7 to 20.0 ± 0.6 mmHg, P < 0.01. Mean OPP was unchanged from baseline levels after the addition of pilocarpine in both the diurnal and nocturnal periods. Mean systolic BP was significantly reduced during the nocturnal period only (-3.16 ± 1.5 mmHg, P = 0.03).

CONCLUSIONS

In patients taking PGA monotherapy, the addition of pilocarpine can significantly lower IOP throughout the diurnal and nocturnal periods, but has no effect on OPP.

Initial intraocular pressure reduction by mono- versus multi-therapy in patients with open-angle glaucoma: results from the Glaucoma Intensive Treatment Study

Purpose

To study newly diagnosed glaucoma patients given mono‐ or multi‐therapy regarding differences in initial intraocular pressure (IOP) reduction, target IOP levels reached and influence of untreated baseline IOP on IOP reduction.

Methods

Patients newly diagnosed with manifest primary open‐angle glaucoma and included in the Glaucoma Intensive Treatment Study (GITS) were randomized to immediate intensive treatment with any of three different IOP‐lowering substances supplied in two bottles plus 360° laser trabeculoplasty or to conventional stepwise treatment starting with a single‐drug. Intraocular pressure reduction was analysed 1 month after initiation of treatment.

Results

One hundred eighteen patients (143 eyes) received mono‐therapy and 122 patients (152 eyes) multi‐therapy. Median baseline IOP was 24.0 (min: 9.7, max: 56.0) mmHg in mono‐therapy eyes and 24.0 (min: 12.3, max: 48.5) mmHg in multi‐therapy eyes (p = 0.56). After 1 month in the two groups, respectively, values for median IOP reduction were 6.3 (range: −5.3–31.0) and 11.0 (range: 0.7–34.5) mmHg, and for mean relative decline 26.8 (range: −32.0–55.4) and 46.0 (range: 4.6–81.6) % (p = 0.000). A larger proportion of the multi‐therapy patients reached each target IOP level (p = 0.000). The higher the baseline IOP, the larger the observed pressure reduction, considering both absolute and relative figures. The effect was more pronounced in eyes with multi‐therapy than in those with mono‐therapy (p = 0.000). For every mmHg higher IOP at baseline, the IOP was reduced by an additional 0.56 (mono‐therapy) or 0.84 (multi‐therapy) mmHg.

Conclusion

Intensive treatment led to considerably greater IOP reduction than mono‐therapy. Among patients with IOP ≥30 mmHg at diagnosis an IOP of <16 was reached in 2/3 of those with multi‐therapy but in none with mono‐therapy. The IOP reduction was highly dependent on the untreated IOP level.

Changes in adherence and associated factors among patients on newly introduced prostaglandin analog and timolol fixed-combination therapy

PURPOSE

We investigated patient adherence and factors related to a newly introduced prostaglandin analog and timolol fixed-combination eye drops (PGTFC).

PATIENTS AND METHODS

The Glaucoma Research on Adherence to fixed-Combination Eye drops in Japan (GRACE) study group performed a nationwide prospective questionnaire survey. Participants in this study were patients with glaucoma who were scheduled to receive any type of PGTFC for the first time. The participants answered a questionnaire on the day of PGTFC introduction and again at a return visit 4-6 weeks after PGTFC introduction. The physicians in charge were asked to complete a separate questionnaire on the day of PGTFC introduction. One of two leaflets was randomly delivered to each participant before the description of the PGTFC. One leaflet explained how to correctly instill the eye drops, and the other explained the clinical meaning of intraocular pressure reduction in addition to explaining how to correctly instill the eye drops. Nonadherence was defined as forgetting to instill the eye drops one or more times during the week before the return visit.

RESULTS

In total, 3,597 patients (age, 68.4±12.2 years) met the study protocol requirements. PGTFC introduction significantly reduced the number of antiglaucoma eye drops from 1.93±0.78 to 1.34±0.54 (P<0.0001) and significantly improved adherence (P<0.00001). Factors significantly associated with nonadherence at the return visit included a history of nonadherence as reported by either the patient or their physician before introduction, acceptable instillation times as reported by the patient, and burdensome eye drop instillation as reported by the patient. No significant difference was observed between the two leaflets in terms of their effects on adherence.

CONCLUSION

PGTFC significantly improved adherence and some of the factors that were significantly associated with adherence.

REGISTRATION NUMBER

UMIN000013696.

Preservative-free tafluprost in the treatment of open-angle glaucoma or ocular hypertension in India: a phase III clinical trial

AIM

The aim of this study was to evaluate the efficacy and safety of preservative-free (PF) tafluprost compared with PF timolol in Indian subjects with open-angle glaucoma (OAG) or ocular hypertension.

METHODS

This was a randomised, multicentre, double-masked, phase III trial. Subjects aged 18-80 years, following washout of current medication, with intraocular pressure (IOP) ≥ 24 and ≤ 36 mmHg in at least one eye were randomised in a 1:1 ratio to 0.0015% PF tafluprost or 0.5% PF timolol for 4 weeks. IOP was measured at 08:00, 10:00 and 16:00 hours at baseline and at weeks 2 and 4. The primary efficacy end-point was the mean diurnal IOP change from baseline at week 4, and PF tafluprost was considered non-inferior to PF timolol if the upper bound of the 95% confidence interval (CI) for between-treatment differences was ≤ 1.5 mmHg. The secondary end-point was the proportion of subjects with ≥ 25% reduction in IOP from baseline at week 4.

RESULTS

In total, 190 subjects were randomised, 95 each, to PF tafluprost and PF timolol treatment. PF tafluprost was non-inferior to PF timolol with respect to diurnal IOP changes from baseline over 4 weeks. The mean PF tafluprost-PF timolol difference in the diurnal IOP change was -1.7 (95% CI -2.6 to -0.7), suggestive of superiority for PF tafluprost. The secondary end-point was achieved in a higher proportion of PF tafluprost group subjects. Both PF tafluprost and PF timolol were well-tolerated with similar incidences of adverse events.

CONCLUSIONS

PF tafluprost was safe and efficacious in reducing IOP in Indian subjects.

Long-term assessment of prostaglandin analogs and timolol fixed combinations vs prostaglandin analogs monotherapy

AIM

To draw a Meta-analysis over the comparison of the intraocular pressure (IOP)-lowering efficacy and safety between the commonly used fixed-combinations of prostaglandin analogs and 0.5% timolol with prostaglandin analogs (PGAs) monotherapy.

METHODS

After searching the published reports from MEDLINE, EMBASE, the Cochrane Library, all randomized controlled clinical trials (RCTs) comparing the fixed combination of PGAs/timolol therapy (FCs) and PGAs monotherapy with treatment duration at least 6mo were included. The efficacy outcomes were mean diurnal IOP, percentage of participants whose IOP were lower than 18 mm Hg, incidence of visual field change, while the safety outcomes included corneal side effects, hyperemia and eye irritation. The analysis was carried out in RevMan version 5.3 software.

RESULTS

After six-month medical intervention, the mean diurnal IOP of FCs was lower than PGAs (MD -1.14, 95% CI -1.82 to -0.46, P=0.001); the percentage of target IOP achieving between FCs and PGAs showed no significant difference (RR 1.18, 95% CI 0.97 to 1.43, P=0.10). No statistically significant differences of the incidence of hyperemia (RR 0.67, 95% CI 0.45 to 1.01, P=0.06) and eye irritation (RR 1.20, 95% CI 0.95 to 1.51, P=0.12) between the FCs and PGAs monotherapy were detected. Only one research involved in corneal events, result of this trial revealed no difference between two intervention groups regarding corneal effects (central endothelial cell density, MD -0.20, 95% CI -0.72 to 0.32, P=0.45; central corneal thickness, MD -0.01, 95% CI -0.02 to 0.00, P=0.23). The evaluation of visual field change was not performed due to the limited duration of the trials included in this Meta-analysis.

CONCLUSION

The long-term efficacy of the FCs overweighed the PGAs monotherapy in lowering IOP, but in the incidence of hyperemia and eye irritation syndromes, the differences are not statically significant. More RCTs with detailed and authentic data over the assessments of visual functions and morphology of optic nerve heads are hoped to be conducted.

Effects of prostaglandin analogues on aqueous humor outflow pathways

Elevated intraocular pressure (IOP) is the most prevalent risk factor for glaucoma. All treatments, whether surgical or pharmaceutical, are aimed at lowering IOP. Prostaglandin analogues are a first line therapy for glaucoma due to their ability to reduce IOP, once-daily dosing, efficacy, and minimal side-effect profile. Whereas prostaglandin analogues have been known to alter aqueous humor outflow through the unconventional (uveoscleral) pathway, more recent evidence suggests their action also occurs through the conventional (trabecular) pathway. Understanding how prostaglandin analogues successfully lower IOP is important, as this information may lead to the discovery of new molecular targets for future therapeutic intervention. This review explores the current understanding of prostaglandin analogue biology as it pertains to IOP reduction and improved aqueous humor outflow facility.

Prostaglandin analogs and timolol-fixed versus unfixed combinations or monotherapy for open-angle glaucoma: a systematic review and meta-analysis

PURPOSE

To estimate the intraocular pressure (IOP)-lowering effect of prostaglandin analogs (PGAs) administered in combination with β-blockers.

METHODS

We searched the Medline and Embase databases for randomized trials comparing topical therapies with PGAs and timolol administered as monotherapy (Mt), or in fixed (FC) or unfixed combinations (UC) to patients with glaucoma or ocular hypertension. The efficacy endpoint was the mean difference (MeD) in the reduction in IOP from baseline; the tolerability endpoint was the incidence of hyperemia.

RESULTS

The 18 eligible trials involved 23 comparisons of FC versus Mt, and 5 of FC versus UC. The FCs were less efficacious than UCs (MeD: 0.69, 95% CI: 0.29 to 1.08). In comparison with timolol Mt, the latanoprost/timolol FC led to a greater IOP reduction (MeD: -2.74, 95% CI: -3.24 to -2.23) than the bimatoprost/timolol FC (MeD: -1.49, 95% CI: -1.86 to -1.12) or the travoprost/timolol FC (MeD: -1.93, 95%CI: -2.98 to -0.88). The FCs led to a lower hyperemia risk than UCs [relative risk (RR): 0.70, 95% CI: 0.43 to 1.14] and PGA Mt (RR: 0.61, 95% CI: 0.53 to 0.70).

CONCLUSIONS

FCs are more efficacious than their individual components, but less efficacious than their respective UCs. FCs lead to a lower hyperemia risk than UCs and their respective PGA Mts.

Randomized clinical trial of the efficacy and safety of preservative-free tafluprost and timolol in patients with open-angle glaucoma or ocular hypertension

PURPOSE

To compare the efficacy and safety of tafluprost, a preservative-free (PF) prostaglandin analogue, with PF timolol in patients with open-angle glaucoma or ocular hypertension.

DESIGN

Randomized, double-masked, multicenter clinical trial.

METHODS

After discontinuation and washout of existing ocular hypotensive treatment, patients who had intraocular pressure (IOP) ≥23 and ≤36 mm Hg in at least 1 eye at the 08:00 hour time point were randomized 1:1 to 12 weeks of treatment with either PF tafluprost 0.0015% or PF timolol 0.5%. IOP was measured 3 times during the day (08:00, 10:00, 16:00 hours) at baseline and at weeks 2, 6, and 12. It was hypothesized that PF tafluprost would be noninferior to PF timolol over 12 weeks with regard to change from baseline IOP. The trial was powered for a noninferiority margin of 1.5 mm Hg at each of the 9 time points assessed.

RESULTS

A total of 643 patients were randomized and 618 completed (PF tafluprost = 306, PF timolol = 312). IOPs at the 3 time points assessed during the baseline visit ranged from 23.8 to 26.1 mm Hg in the PF tafluprost group and 23.5 to 26.0 mm Hg in the PF timolol group. IOPs at the 3 time points assessed during the 12-week visit ranged from 17.4 to 18.6 mm Hg for PF tafluprost and 17.9 to 18.5 mm Hg for PF timolol. At all 9 time points, the upper limits of the 2-sided 95% confidence intervals for the difference between treatments in IOP lowering were less than the prespecified noninferiority margin. Similar percentages of PF tafluprost and PF timolol patients reported ocular pain/stinging/irritation (4.4% vs 4.6%) and pruritus (2.5% vs 1.5%). The percentages of PF tafluprost and PF timolol patients reporting conjunctival hyperemia were 4.4% vs 1.2% (nominal P = .016).

CONCLUSIONS

The IOP-lowering effect of PF tafluprost was noninferior to that of PF timolol. PF tafluprost is an efficacious and generally well-tolerated ocular hypotensive agent.

Efficacy and tolerability of prostaglandin-timolol fixed combinations: a meta-analysis of randomized clinical trials

PURPOSE

To evaluate the intraocular pressure (IOP)-lowering effects and tolerability of the 3 prostaglandin-timolol fixed combinations (PG-timolol FCs).

METHODS

Clinical trials comparing directly the PG-timolol FCs or comparing the PG-timolol FCs to their individual components were thoroughly searched. The main outcome measures were efficacy assessed by IOP (taken at 9 am, noon, 4 pm, and over the mean diurnal curve) change at 3 months (or after 1 to 6 months of treatment if no data were available at month 3) from baseline and tolerability assessed by the incidence of conjunctival hyperemia.

RESULTS

Twenty trials were identified (n = 4684 patients). Intraocular pressure reduction was usually greater with the 3 PG-timolol FCs than the individual PG (mean difference [MD] 0.00 mmHg to 2.59 mmHg; p>0.1 to p<0.001). The incidence of hyperemia was significantly less with latanoprost- and bimatoprost-timolol FCs than with the individual PG (relative risk = 0.66 and 0.61; p = 0.05 and p<0.001). From direct comparisons, IOP reduction was significantly greatest with bimatoprost-timolol FC, at 9 am, 4 pm, and over the mean diurnal curve compared to latanoprost-timolol FC (MD = 0.90 mmHg to 1.48 mmHg; p<0.001) and at all time points compared to travoprost-timolol FC (MD = 0.66 mmHg to 0.90 mmHg; p<0.001). The incidence of hyperemia was not significantly less with latanoprost-timolol FC than with bimatoprost-timolol FC (relative risk = 1.32; p>0.1).

CONCLUSIONS

The 3 PG-timolol FCs provide a greater IOP reduction and lower incidence of hyperemia than the 3 PGs alone. The direct comparisons suggest a greater efficacy of the bimatoprost-timolol FC compared with latanoprost- and travoprost-timolol FCs.

Twenty-four hour efficacy with the dorzolamide/timolol-fixed combination compared with the brimonidine/timolol-fixed combination in primary open-angle glaucoma

AIM

The aim of this study is to compare the 24-hour efficacy of dorzolamide/timolol-fixed combination (DTFC) and brimonidine/timolol-fixed combination (BTFC) in primary open-angle glaucoma (POAG).

METHODS

One eye each of 77 POAG patients was included in this prospective, observer-masked, crossover comparison. Following a 2-month timolol run-in period, patients had three intraocular pressure (IOP) measurements at 1000, 1200 and 1400 h while on timolol treatment. Patients showing at least a 20% IOP reduction on timolol were randomised to 3 months of therapy with DTFC or BTFC, and then were crossed over to the opposite therapy.

RESULTS

Sixty POAG patients completed the study. The mean 24-hour IOP was significantly reduced with both the fixed combinations compared with the timolol-treated diurnal IOP (P < 0.001). When the two fixed combinations were compared directly, DTFC demonstrated a lower mean 24-hour IOP level as compared with BTFC (mean difference: -0.7 mm Hg, 95% confidence interval (CI): (-1.0, -0.3), P < 0.001). At two individual time points, DTFC significantly reduced IOP more than BTFC: at 1800 h (-1.0 mm Hg, 95% CI (-1.6,-0.5), P = 0.001) and at 0200 (-0.9 mm Hg, 95% CI: (-1.4,-0.5), P = 0.001). No significant difference existed for the other time points.

CONCLUSION

Both the fixed combinations significantly reduce 24-hour IOP in POAG. DTFC provided significantly better 24-hour efficacy.

Bimatoprost and bimatoprost/timolol fixed combination in patients with open-angle glaucoma and ocular hypertension

PURPOSE

To investigate the intraocular pressure (IOP) lowering effect of bimatoprost (BIM) 0.03% and the potential additional effect of the BIM 0.03%/timolol 0.5% fixed combination (BTFC) in eyes with ocular hypertension, primary open-angle glaucoma, or exfoliation glaucoma.

METHODS

Following an appropriate washout period that varied with previous medication, participants with ocular hypertension, primary open-angle glaucoma, or exfoliation glaucoma were treated with evening-dosed BIM for 5 weeks. They were then given evening-dosed BTFC for another 5 weeks. One randomly selected eye was evaluated. Goldmann applanation tonometry was performed by the same investigator at 8 a.m., 12 noon, 4 p.m., and 8 p.m. at baseline and at the end of each treatment period.

RESULTS

Thirty-three participants completed the study. Three patients discontinued because of local adverse effects during the BIM treatment period. The mean diurnal IOP (mean ± SD) at baseline, on BIM, and on BTFC were 24.8 ± 5.4, 17.3 ± 3.5, and 14.9 ± 3.1 mmHg, respectively (repeated measures analysis of variance, P < 0.001 for all pairwise comparisons). The individual time-point IOP values showed similar significant reductions. The percentage of IOP reduction from baseline was 30.2% for BIM and 39.9% for the BTFC. The mean ± SD diurnal fluctuation at baseline was 6.8 ± 3.2 mmHg, which decreased to 4.0 ± 3.1 and 2.9 ± 1.4 mmHg on BIM and BTFC, respectively (P < 0.05 for both treatments versus baseline).

CONCLUSIONS

Both BIM 0.03% and the BTFC were effective in lowering IOP in eyes with ocular hypertension and open-angle glaucoma. However, the fixed combination provided an additional statistically significant reduction in IOP compared with BIM 0.03%.

Comparison of ocular hypotensive actions of fixed combinations of brimonidine/timolol and dorzolamide/timolol

OBJECTIVE

To compare brimonidine/timolol fixed combination (BrTFC; Combigan *) with dorzolamide/timolol fixed combination (DTFC; Cosopt dagger) in terms of ability to lower intraocular pressure (IOP) in primary open-angle glaucoma (POAG).

METHODS

This was a prospective, randomized, double-masked, crossover study. After 6 weeks of therapy with timolol maleate 0.5% twice daily, patients were randomized to BrTFC twice daily or DTFC twice daily for 6 weeks, before being crossed over to the other treatment arm for a further 6 weeks. At all follow-up visits, IOP was measured at 09.00 (pre-instillation) 12.00 and 16.00. The primary outcome measure was change in mean diurnal IOP from baseline at 6 weeks. The secondary outcome was percentage of patients with IOP <18 mmHg at 6 weeks. Data were analyzed from all patients who completed the study.

RESULTS

Twenty-five patients were randomized and 20 completed the study. Mean diurnal IOP (mean +/- standard deviation [SD]) was 20.28 +/- 2.03 mmHg at timolol-treated baseline. After 6 weeks, mean diurnal IOP was 16.28 +/- 2.07 mmHg following BrTFC and 17.23 +/- 2.29 mmHg following DTFC (difference: 0.95 mmHg, 95% CI 0.10-1.80, p = 0.03). Mean IOP at 09.00 was 20.95 +/- 2.31 mmHg at baseline. This was reduced to 15.85 +/- 2.56 mmHg following BrTFC and 17.55 +/- 2.67 mmHg following DTFC (difference: 1.70, 95% CI 0.80-2.60, p = 0.001). For the 12.00 and 16.00 timepoints, the mean changes from baseline in the two arms were comparable. Percentages of patients achieving a target IOP of <18 mmHg were 85% following BrTFC and 60% following DTFC (p = NS [not significant]). No treatment-related adverse events were reported with either therapy. Key limitations include the small size of the study population and the 6-week duration of treatment periods, which prevents drawing conclusions regarding long-term therapy.

CONCLUSION

Reductions from baseline in mean diurnal IOP and morning IOP were greater with BrTFC than with DTFC.

Fixed combinations of dorzolamide-timolol and brimonidine-timolol in the management of glaucoma

IMPORTANCE OF THE FIELD

The emergence of fixed-combination drugs for the treatment of glaucoma has, to some extent, changed the medical management of glaucoma. The potential benefits of these drugs include a reduction in the total number of drops and preservatives instilled per day and improved patient comfort factors, which may contribute to better compliance. Combination medications may also improve therapeutic efficacy and play an important role in controlling medication cost. However, the fixed dosing may be a disadvantage in some cases.

AREA COVERED IN THIS REVIEW

This review describes the composition, pharmacokinetics, mode of action, efficacy, side effects, and safety profile of fixed-combination dorzolamide-timolol and fixed-combination brimonidine-timolol.

WHAT THE READER WILL GAIN

Understanding of the pros, cons, and safety profile of two FDA approved fixed-combination antiglaucoma medication.

TAKE HOME MESSAGE

Fixed-combination medications may be a reasonable adjunct to prostaglandins if a large drop in the intraocular pressure (IOP) is desired and adding only one medication is unlikely to reach the target IOP range. Both mentioned drugs are effective in reducing the IOP and further clinical studies will help identify differences in efficacy between the two. The clinician must make an individualized assessment of the medication's risk-benefit profile for each patient.