A randomised crossover study comparing bimatoprost and latanoprost in subjects with primary angle closure glaucoma

Cytotoxicity, Mitochondrial Functionality, and Redox Status of Human Conjunctival Cells after Short and Chronic Exposure to Preservative-Free Bimatoprost 0.03% and 0.01%: An In Vitro Comparative Study

Prostaglandin analogues (PGAs), including bimatoprost (BIM), are generally the first-line therapy for glaucoma due to their greater efficacy, safety, and convenience of use. Commercial solutions of preservative-free BIM (BIM 0.03% and 0.01%) are already available, although their topical application may result in ocular discomfort. This study aimed to evaluate the in vitro effects of preservative-free BIM 0.03% vs. 0.01% in the human conjunctival epithelial (HCE) cell line. Our results showed that long-term exposure to BIM 0.03% ensues a significant decrease in cell proliferation and viability. Furthermore, these events were associated with cell cycle arrest, apoptosis, and alterations of ΔΨ_m. BIM 0.01% does not exhibit cytotoxicity, and no negative influence on conjunctival cell growth and viability or mitochondrial activity has been observed. Short-time exposure also demonstrates the ability of BIM 0.03% to trigger reactive oxygen species (ROS) production and mitochondrial hyperpolarisation. An in silico drug network interaction was also performed to explore known and predicted interactions of BIM with proteins potentially involved in mitochondrial membrane potential dissipation. Our findings overall strongly reveal better cellular tolerability of BIM 0.01% vs. BIM 0.03% in HCE cells.

Guidelines for treatment of chronic primary angle-closure glaucoma

OBJECTIVE

To present a clinical practice guideline update on the medical, laser, and surgical treatment of primary angle closure glaucoma (PACG) in adults.

METHODS

Following the formulation of key questions using the PICO scheme (Patient/Problem, Intervention, Comparison, Outcome), a systematic review was performed on the literature published to date, including international clinical practice guidelines. The AMSTAR and Risk of Bias tools were used for evaluating the quality of the information. The level of evidence and grade of recommendation was established following the Scottish Intercollegiate Guidelines Network (SIGN) system.

RESULTS

Following the above methodology, recommendations of medical, laser and surgical treatment in adult PACG and levels of evidence are presented.

CONCLUSIONS

Although the level of scientific evidence for many of the questions raised is not very high, a review is presented on updated treatment recommendations for adult PACG. Among the limitations for the implementation of these recommendations is that most studies have been conducted in Asian populations, and that the effectiveness is measured almost exclusively in terms of reducing intraocular pressure, and does not include visual function, quality of life or cost-effectiveness parameters.

Latanoprost in the treatment of glaucoma

Prostaglandins are approved by the European Glaucoma Society guidelines as first-line treatment for glaucoma. This review focuses on latanoprost, an ester prodrug of prostaglandin (PG) F_2α, which was the first of the currently available topical PGF_2α analogs to be launched for glaucoma or ocular hypertension and which still accounts for the majority of prescriptions. It is better absorbed than the parent compound through the cornea, and peak concentration of the active drug is in the aqueous humor 1–2 hours after topical dosing (15–30 ng/mL). Metabolism occurs mainly in the liver. Latanoprost (0.005%) has been very well studied in clinical trials and meta-analyses that show it to be generally as effective as the other PG analogs (bimatoprost, travoprost, and tafluprost) and more effective than timolol, dorzolamide, and brimonidine. Latanoprost has good short- and long-term safety and tolerability profiles. In common with other prostaglandins, it lacks systemic effects, but can cause ocular adverse events such as conjunctival hyperemia, pigmentation of the iris, periocular skin or eyelashes, hypertrichosis, and ocular surface effects or irritation. Latanoprost is significantly better tolerated than either bimatoprost or travoprost. Patients treated with latanoprost have better compliance and persist with therapy longer than those that are given other drugs. An improved formulation of latanoprost without the preservative benzalkonium chloride has recently been developed. It is as effective as conventional latanoprost, has a lower incidence of hyperemia, and can be stored at room temperature. In conclusion, latanoprost has the best efficacy–tolerability ratio of the PG analogs available for glaucoma treatment, and has good compliance and persistence. These factors should be improved further by the recent development of preservative-free latanoprost.

Meta-analysis of randomized controlled trials comparing latanoprost with other glaucoma medications in chronic angle-closure glaucoma

PURPOSE

To evaluate the efficacy and safety of latanoprost compared with other glaucoma medications in the treatment of chronic angle-closure glaucoma (CACG) and to provide the basis for clinical medication.

METHODS

Major literature databases were searched for randomized controlled trials (RCT) involving latanoprost among patients with CACG. Primary outcome measures were absolute changes in intraocular pressure (IOP) and incidence of ocular adverse events. Statistical analyses included the calculation of standardized mean difference (SMD) and relative risk (RR). The statistical analysis was performed using STATA version 12.0 software.

RESULTS

Ten RCT involving 1096 patients were included in this meta-analysis. Analysis showed that latanoprost was not significantly different from other glaucoma medications in reducing IOP (SMD = 0.29, 95% confidence interval [CI] -0.02 to 0.59, p=0.069). Further subgroup analysis revealed that latanoprost was superior compared with timolol (SMD = 0.64, 95% CI 0.46 to 0.82, p<0.001) and marginally inferior to travoprost and bimatoprost (SMD = -0.19, 95% CI -0.35 to -0.02, p = 0.026). As for conjunctival hyperemia, latanoprost caused a higher proportion than timolol (RR = 2.36, 95% CI 1.27 to 4.37, p = 0.007). However, latanoprost was associated with lower incidence of conjunctival hyperemia (RR = 0.42, 95% CI 0.30 to 0.59, p<0.001), and with fewer occurrence of other ocular side effects (excluding conjunctival hyperemia) than travoprost and bimatoprost (RR = 0.61, 95% CI 0.48 to 0.78, p<0.001).

CONCLUSIONS

Travoprost and bimatoprost are superior in IOP control than latanoprost, but latanoprost is better tolerated in patients with CACG.

Effects of benzalkonium chloride on the blood-aqueous and blood-retinal barriers of pseudophakic eyes

PURPOSE

To evaluate the effects of benzalkonium chloride (BAK) on the blood-aqueous (BAB) and blood-retinal barriers (BRB) of pseudophakic eyes.

METHODS

Prospective, randomized, investigator-masked, comparative study. Patients were randomly assigned to preservative-free artificial tears or BAK-preserved artificial tears. One drop of artificial tears was instilled 4 times a day in the study eye, starting the day after randomization for 30 days. Anterior chamber flare was assessed by a laser flare meter (LFM) and macular thickness measurements were obtained with optical coherence tomography, before, 15, and 30 days after randomization.

RESULTS

A total of 44 healthy eyes of 44 pseudophakic volunteers were recruited. There were no significant differences regarding demographics (age, gender, and race distributions) and clinical characteristics (eye, mean intraocular pressure, and mean best-corrected visual acuity) between the 2 groups (P>0.05). No significant differences in baseline mean LFM values were observed (P=0.262). However, we detected a statistically significant increase in mean LFM measurements in the BAK-preserved group (11.4 ± 5.1 ph/ms) (P=0.017) after 15 days. After 30 days, the BAK-preserved group maintained significantly higher flare values (11.9 ± 5.9 ph/ms) compared with baseline (P=0.043). On the other hand, the preservative-free group showed mean flare values of 8.4 ± 2.5 ph/ms, not significantly different from those obtained at baseline (P=1.00). We observed no statistically significant change in macular thickness measurements at days 15 and 30 in either group (P>0.05). Cystoid macular edema was not detected in this series.

CONCLUSIONS

Our results suggest that a short-term exposure to BAK can cause disruption of the BAB, without altering the BRB in pseudophakic eyes.

Bimatoprost 0.01% vs bimatoprost 0.03%: a 12-month prospective trial of clinical and in vivo confocal microscopy in glaucoma patients

PURPOSE

To evaluate the safety of two commercially available formulations of bimatoprost eye drops: 0.03 and 0.01% ophthalmic solutions.

METHODS

This was a randomized, prospective, parallel-group, open-label, cohort study. A total of 60 glaucoma patients (60 eyes) under bimatoprost 0.03% monotherapy since at least 1 year were enrolled. Selected patients were randomized to receive a single drop of bimatoprost 0.01% (n=30) or bimatoprost 0.03% (n=30) ophthalmic solutions for 12 months. Statistical analysis was performed using paired t-test and repeated measures ANOVA test.

RESULTS

Global clinical score (the sum of pruritus, stinging/burning, blurred vision, sticky eye sensation, eye dryness sensation, and foreign body sensation) significantly decreased in the bimatoprost 0.01% group from baseline 4.7 ± 3.8 to 2.9 ± 2.3 (P < 0.001) and 2.5 ± 2.0 (P < 0.001) at 6-month and 12-month follow-ups, respectively. Comparison between groups showed differences at both follow-up visits (P = 0.003 and P < 0.001, respectively). In vivo confocal microscopy revealed a significant increase in goblet cell density in the bimatoprost 0.01% group compared with the bimatoprost 0.03% group (P<0.001 at both follow-up visits). All functional parameters and conjunctival hyperemia improved in the bimatoprost 0.01% group at each follow-up visit (P < 0.05) and in comparison with bimatoprost 0.03% (P < 0.05).

CONCLUSION

The results of this trial suggest that bimatoprost 0.01% eye drops seem to decrease the ocular discomfort with respect to bimatoprost 0.03% eye drops.

Efficacy of goniosynechialysis for advanced chronic angle-closure glaucoma

Purpose:

To evaluate the intraocular pressure (IOP)-lowering efficacy of goniosynechialysis (GSL) for advanced chronic angle-closure glaucoma (CACG) using a simplified slit-lamp technique.

Patients and methods:

Patients with CACG with one severely affected eye with best-corrected visual acuity below 20/200 and a mildly or functionally unaffected fellow eye were enrolled in this study. All patients underwent ophthalmologic examinations including measurement of visual acuity, best-corrected visual acuity, and IOP; biomicroscopy; specular microscopy; fundus examination; and gonioscopy followed by anterior chamber paracentesis and GSL for nasal peripheral anterior synechiae in the eye with severe CACG.

Results:

Thirty patients (18 men, 12 women) were identified as having CACG with an initial mean IOP of 47.1 ± 6.7 mmHg (range 39–61 mmHg) in the severely affected eye. One week after GSL, the mean IOP of the treated eyes decreased to 19.3 ± 2.8 mmHg (range 14–26 mmHg) without antiglaucoma medication (average decrease 27.7 ± 6.5 mmHg; range 16–41 mmHg), which was significant (P < 0.00001) compared with baseline. After an average follow-up period of 36.6 ± 1.0 months (range 35–38 months), the mean IOP stabilized at 17.4 ± 2.2 mmHg (range 12–21 mmHg). The nasal angle recess did not close again in any one of the patients during the follow-up period. The average significant (P < 0.00001) decrease in corneal endothelial cell density in the treated eyes was 260 ± 183 cells/mm² (range 191–328 cells/mm²).

Conclusions:

Anterior chamber paracentesis and GSL lowers IOP in advanced CACG, though it may lead to mild corneal endothelial cell loss.

Efficacy of bimatoprost 0.03% in reducing intraocular pressure in patients with 360° synechial angle-closure glaucoma: a preliminary study

Context:

Peripheral anterior synechiae (PAS; synechiae anterior to functional trabecular meshwork) formation in primary angle-closure glaucoma (PACG) hampers access to uveoscleral outflow. Thus, the role of bimatoprost in such patients with 360° synechiae was evaluated.

Aims:

To assess efficacy and safety profile of bimatoprost 0.03% in lowering intraocular pressure (IOP) in 360° synechial angle-closure glaucoma patients.

Settings and Design:

This was a prospective, non-randomized, non-comparative, selective analysis, single-center pilot study.

Materials and Methods:

A total of 23 eyes of 20 Indian chronic angle-closure glaucoma (CACG) patients with IOP greater than 21 mmHg, 360° PAS and no visual potential in the study eye underwent detailed eye examination. Baseline IOP was measured and YAG peripheral iridotomy was performed for complete angle-closure reconfirmation. Bimatoprost 0.03% was administered for 8 weeks as once-daily evening dose. IOP reduction within treatment group was determined with “paired t-test”.

Results:

The mean reduction in IOP from baseline to 8 weeks of bimatoprost therapy was 15.3 ± 9.5 mmHg (P < 0.001). The most commonly observed adverse event was conjunctival hyperemia (35%). Bimatoprost was well tolerated in the study.

Conclusions:

In this study, exclusively involving patients with 360° synechial angle-closure glaucoma and no visual potential, bimatoprost 0.03% treatment demonstrated a statistically significant IOP reduction. Hence, it can be inferred that bimatoprost 0.03% is an efficacious treatment modality in this subgroup of patients for reducing IOP.

Aqueous humor penetration of topical bimatoprost 0.01% and bimatoprost 0.03% in rabbits

Purpose

The purpose of this study was to compare the aqueous humor concentrations of bimatoprost acid after topical instillation in rabbits of bimatoprost ophthalmic solution 0.01% and bimatoprost ophthalmic solution 0.03%, two commercially available intraocular pressure-lowering medications.

Methods

Male Dutch Belted rabbits were divided into two treatment groups (four rabbits/eight eyes per group): bimatoprost 0.01% and bimatoprost 0.03%. Thirty microliters (μL) of study medication was to pically instilled into both eyes of each animal. Thirty minutes and 90 minutes after instillation, aqueous humor samples were collected. These samples were analyzed by reverse-phase high-performance liquid chromatography for bimatoprost acid concentration.

Results

Following a single topical ocular instillation, the bimatoprost 0.01% formulation had a lower mean aqueous humor concentration of bimatoprost acid than the bimatoprost 0.03% formulation at both 30 minutes (11.5 ± 2.1 ng/mL versus 37.8 ± 28.8 ng/mL; P = 0.17) and 90 minutes (20.8 ± 5.7 ng/mL versus 45.8 ± 14.3 ng/mL; P = 0.03) after topical instillation.

Conclusions

Topical ocular instillation of bimatoprost 0.01% produced significantly lower bimatoprost acid concentration in the aqueous humor of rabbits than bimatoprost 0.03%, despite the 4-fold increase of benzalkonium chloride contained in bimatoprost 0.01%.

Bimatoprost: a review of its use in open-angle glaucoma and ocular hypertension

Bimatoprost (Lumigan) is a synthetic prostamide that reduces intraocular pressure (IOP) by increasing the outflow of aqueous humour. In patients with open-angle glaucoma or ocular hypertension, long-term treatment (for up to 48 months) with once-daily bimatoprost 0.03% ophthalmic solution was more effective than timolol twice daily in providing a sustained and stable reduction in IOP. Bimatoprost 0.03% ophthalmic solution demonstrated efficacy similar to, or greater than, the prostaglandin analogues latanoprost and travoprost in reducing IOP and achieving target IOP levels. Switching to bimatoprost was as effective in maintaining diurnal IOP control as switching to a fixed combination of latanoprost/timolol (in patients with IOP levels controlled with a nonfixed combination of latanoprost plus timolol), and similarly, or more, effective in lowering IOP and providing overall diurnal IOP control than switching to a combination of dorzolamide/timolol (in patients with IOP inadequately controlled with other antiglaucoma agents including timolol). Treatment with bimatoprost was generally well tolerated, with conjunctival hyperaemia (mostly mild), growth of eyelashes and ocular pruritus being commonly reported. Other adverse events included increases in the pigmentation of the iris, perorbital areas and eyelashes.

Bilateral phacomorphic angle-closure glaucoma in a highly myopic patient secondary to isolated spherophakia

BACKGROUND

Angle closure most commonly occurs in older hyperopic patients as a result of primary relative pupil block. Less frequently, angle closure occurs in highly myopic patients with conditions other than primary relative pupil block. This report presents the diagnosis, pathophysiologic mechanism, and management of a patient with both high myopia and bilateral advanced phacomorphic angle-closure glaucoma caused by isolated spherophakia.

CASE

A 40-year-old asymptomatic man with very high myopic astigmatism presented with chronic angle closure and an intraocular pressure of 42 mmHg in both eyes. Additionally there was a nonmyopic fundus and 24-mm axial length, with a clear crystalline lens protruding through the pupillary plane in each eye, confirmed by B-scan ultrasonography. Gonioscopy and A-scan and B-scan ultrasonography identified the pathogenesis of intraocular pressure elevation, angle closure, and high myopia to be lenticular in origin. Initial medical therapy and subsequent laser iridotomy relieved the pupil block angle closure and successfully lowered intraocular pressure.

CONCLUSION

Angle closure can occur in highly myopic eyes. Careful gonioscopy and ultrasonography can lead to the correct diagnosis and tailored management for these eyes. Phacomorphic angle-closure glaucoma from spherophakia is associated with Weill-Marchesani syndrome as well as a few other uncommon syndromes. Isolated pseudophakia is a rarely reported cause of phacomorphic angle closure.

Impact of topical bimatoprost 0.01% and bimatoprost 0.03% on conjunctival irritation in rabbits

INTRODUCTION

The purpose of this study was to examine and compare the conjunctival irritation (congestion, swelling, and discharge) of topical bimatoprost ophthalmic solution 0.01% and bimatoprost ophthalmic solution 0.03% in rabbits.

METHODS

Six healthy New Zealand White rabbits were treated with either bimatoprost 0.01% or bimatoprost 0.03% (3 animals/group). One dose (2 drops/dose) of study medication was administered to the right eye of each animal every 30 minutes for 4.5 hours. Approximately 1 hour after the last dose, conjunctival irritation was assessed using a slit-lamp biomicroscope to individually evaluate conjunctival congestion, swelling, and discharge.

RESULTS

The mean conjunctival congestion, swelling and discharge scores for bimatoprost 0.03% were 1.67, 0.33 and 0.33, respectively, and for bimatoprost 0.01% were 2.00, 0.33 and 1.33, respectively.

CONCLUSIONS

Despite the lower drug concentration of the 0.01% formulation, bimatoprost 0.01% does not reduce conjunctival irritation, including conjunctival congestion, swelling, and discharge, in rabbits compared to bimatoprost 0.03%. Further studies would be needed to determine whether the increase in the mean conjunctival congestion and discharge scores may be attributed to the increased BAK concentration in the bimatoprost 0.01% formulation.

Bimatoprost - a review

Bimatoprost is a synthetic prostamide analog that is efficacious in the treatment of open-angle glaucoma, ocular hypertension and other forms of glaucoma. It reduces intraocular pressure (IOP) by increasing uveoscleral and trabecular outflow. When used as a 0.03% topical preparation once daily, it demonstrates sustained lowering of IOP of 7 - 8 mmHg over a 24-h period. The drug has been found to be more effective than timolol. In some studies it has shown greater ability to lower IOP when compared with other prostaglandin analogs; whereas in others all three clinically used prostaglandin analogs were found to be equally effective. It shows good IOP reduction when used in combination with other glaucoma medications. A common side effect includes mild conjunctival hyperemia, which is generally reversible. Other side effects include periorbital pigmentation, discomfort, ocular surface hyperemia and skin changes. Pharmacoeconomic data indicate that bimatoprost is cost effective in the treatment of open-angle glaucoma.

Role of prostaglandins and specific place in therapy of bimatoprost in the treatment of elevated intraocular pressure and ocular hypertension: A closer look at the agonist properties of bimatoprost and the prostamides

Bimatoprost is the only representative of a novel class of prostaglandin ethanolamide (prostamide) compounds used therapeutically as an efficacious treatment for glaucoma. The pathways through which bimatoprost works to improve uveoscleral outflow to relieve elevated intraocular pressure are similar to those of the conventional prostaglandins used in glaucoma therapy, with some evidence of a preferential action at the trabecular meshwork. The pharmacology of bimatoprost is however, unclear. Pharmacological evidence supports a specific and distinct receptor-mediated agonist activity of bimatoprost at ‘prostamide’ receptors, which is selective to the prostamides as a class. However, other studies have reported either activity of bimatoprost at additional prostanoid and nonprostanoid receptors, or a conversion of bimatoprost to metabolites with agonist activity at prostaglandin FP receptors in the human eye. The formation of endogenous prostamides has been demonstrated in vivo, by a novel pathway involving the cyclooxygenase-2-mediated conversion of endogenous cannabinoid (endocannabinoid) substrates. Irrespective of the pharmacology of bimatoprost and the prostamides in general, further studies are needed to determine the biological role and biochemical pathology of prostamides in the human eye, particularly in glaucoma. Such studies may improve our understanding of uveoscleral flow and may offer new treatments for controlling intraocular pressure.