Ocular Symptoms and Signs with Preserved and Preservative-Free Glaucoma Medications

Efficacy and safety of 0.0015% tafluprost versus 0.005% latanoprost in primary open angle glaucoma, ocular hypertension: a Meta-analysis

AIM

To evaluate the intraocular pressure (IOP)-lowering efficacy and safety of tafluprost 0.0015% eye drops [benzalkonium chloride (BAK) 0.1 mg/mL] compared with that of latanoprost 0.005% eye drops (BAK 0.2 mg/mL) for primary open angle glaucoma (POAG) and ocular hypertension (OHT).

METHODS

All the randomized controlled trials (RCTs) about treating POAG and OHT comparing tafluprost and latanoprost were collected by searching PubMed, Embase, Cochrane Library, CNKI and VIP. The outcomes of interest to evaluate the clinical efficacy and adverse effects included IOP and patient-related drop discomfort.

RESULTS

Five RCTs involving 888 glaucoma patients were included. The results showed that, 1) at the end of the study, no statistically significant differences were observed in IOP reduction [standard mean difference (SMD) =0.48, 95%CI 0.07 to 0.88, P=0.085] between tafluprost and latanoprost; 2) No statistically significant differences were observed in adverse events of foreign-body sensation [relative risk (RR) =0.62, 95%CI 0.26 to 1.46, P=0.269], eye irritation (RR=1.16, 95%CI 0.49 to 2.75, P=0.744), eye pain (RR=2.000, 95%CI 0.949 to 4.216, P=0.07), iris hyper-pigmentation (RR=0.741, 95%CI 0.235 to 2.334, P=0.61), dry eye (RR=1.154, 95%CI 0.409 to 3.256, P=0.79) and eye pruritus (RR=1.600, 95%CI 0.536 to 4.774, P=0.4) between tafluprost and latanoprost. However, tafluprost showed more reported incidence of conjunctival hyperaemia than latanoprost (RR=2.11, 95%CI 1.24 to 3.59, P=0.006).

CONCLUSION

Tafluprost 0.0015% eye drops (BAK 0.1 mg/mL) and latanoprost 0.005% eye drops (BAK 0.2 mg/mL) are comparable in lowering IOP for open angle glaucoma (OAG) and OHT. It does not differ in the incidence of foreign-body sensation, eye irritation, eye pain, iris hyper-pigmentation, dry eye and eye pruritus, but tafluprost shows less ocular tolerability because of more incidence of conjunctival hyperaemia.

Fixed-combination Bimatoprost/Brimonidine/Timolol in Glaucoma: A Randomized, Masked, Controlled, Phase III Study Conducted in Brazil☆

PURPOSE

Many patients with open-angle glaucoma eventually require >2 medications to lower their intraocular pressure (IOP). Fixed-combination ophthalmic solutions can be advantageous in patients who require multiple medications, but the number of fixed combinations combining 3 complementary IOP-lowering agents remains limited. This study assessed the efficacy and safety of a triple fixed combination (TFC) of bimatoprost 0.01%/brimonidine 0.15%/timolol 0.5% ophthalmic solution in patients with primary open-angle glaucoma (POAG) or ocular hypertension (OHT), compared with a dual fixed combination (DFC) of brimonidine 0.2%/timolol 0.5%.

METHODS

Patients with a baseline IOP of 23-34 mm Hg in both eyes and no history of IOP-lowering procedures were eligible for participation in this multicenter, double-masked, randomized, Phase III study. After washout of previous treatment (if applicable), patients were randomized to receive TFC or DFC twice daily in each eye for 3 months. The primary efficacy variable was the change from baseline in mean IOP in the worse eye at week 12 in the modified intent-to-treat (mITT) population. TFC was superior to DFC if the treatment difference (TFC - DFC) favored TFC at week 12 (P ≤ 0.05; 2-sample t test). Secondary and sensitivity analyses were also performed. Safety, including adverse events, was assessed at all visits.

FINDINGS

The mITT/safety population included 185 patients (TFC, n = 90; DFC, n = 95). TFC superiority was demonstrated at all postbaseline visits (all, P < 0.001) through week 12 (week 12 treatment difference: ─2.17 mm Hg; 95% CI, ─3.12 to ─1.22). While treatment-related conjunctival hyperemia was more frequent with TFC than with DFC (47.8% vs 23.2%; P < 0.001), consistent with the additional presence of bimatoprost in TFC, most cases were mild and the numbers of patient discontinuations at week 12 were similar between the TFC and DFC groups (11 [12.2%] vs 7 [7.4%] patients; P = 0.266). No unexpected adverse events were reported.

IMPLICATIONS

Compared with DFC, TFC provided superior IOP lowering throughout the primary efficacy period. An acceptable tolerability profile was observed through 12 months of use of TFC, offering an effective therapeutic option in patients with POAG or OHT who require multiple medications to control their IOP. Additional studies are required for the assessment of the long-term effects of TFC. ClinicalTrials.gov identifier: NCT01217606.

Effects of topical antiglaucomatous medications on central corneal epithelial thickness by anterior segment optical coherence tomography

PURPOSE

To evaluate the effect of topical antiglaucomatous medications on central corneal epithelial thickness measured by anterior segment optical coherence tomography.

MATERIALS AND METHODS

A total of 153 eyes of 153 patients using topical antiglaucomatous medications and 110 eyes of 110 control subjects were enrolled. Glaucoma type, duration of therapy, the number of drugs, and drops/day were noted in the patient group. Patients and control subjects underwent ocular examinations including Schirmer test, slit lamp examination for tear film break-up time, and anterior segment optical coherence tomography for central corneal thickness and central corneal epithelial thickness. Central corneal epithelial thickness and other data were evaluated separately with regard to glaucoma type, duration of therapy, the number of drops, and drugs in the patient group.

RESULTS

The mean ages of the patients and controls were 60.1 ± 10.8 and 58.7 ± 11.2 years, respectively. The groups were similar with regard to mean age and gender (p = 0.058, p = 0.734, respectively). The median (interquartile range) central corneal thickness was 536 (54) µm in patients and 552 (53) µm in controls (p = 0.011). The median (interquartile range) central corneal epithelial thickness of patients and controls were 56 (4) µm and 60 (8) µm, respectively (p < 0.001). The median (interquartile range) tear film break-up time and Schirmer were 12 (6) s and 10 (8) mm in patients and 16 (2) s and 18 (4) mm in controls, respectively (p < 0.001, p < 0.001). In patient group, there was no significant difference in the median central corneal thickness, central corneal epithelial thickness, and tear film break-up time in terms of glaucoma type, duration of therapy, the number of drugs, and the number of daily drops. Only the median Schirmer test was found to be statistically lower in terms of number of daily eye drops (p = 0.039).

CONCLUSION

Using topical antiglaucomatous medications seems to affect the central corneal epithelial thickness in glaucoma patients. Central corneal epithelial thickness was thinner in glaucoma patients than controls. Anterior segment optical coherence tomography might be helpful to evaluate the effect of antiglaucomatous medications on central corneal epithelial thickness during treatment.

Dose-dependent benzalkonium chloride toxicity imparts ocular surface epithelial changes with features of dry eye disease

PURPOSE

Inclusion of the preservative benzalkonium chloride (BAC) in ophthalmic solutions is prevalent, despite the noted potential for exacerbating dry eye disease (DED). Whilst studies incorporating BAC have assessed its' effects as a mouse model of DED, the impact on limbal epithelia is under-studied. Our investigation aimed to comprehensively assess the impact of different BAC dosing regimens and their suitability as a mouse model of DED.

METHODS

C57BL/6J mice (n = 72) were administered topical BAC (0.05-0.2%) over 7 days. Fluorescein staining, corneal smoothness index, and immuno-histological analyses were applied to determine architectural and cellular changes on the ocular surface following BAC treatment. The effect of BAC (0.0001-0.01%) on cultivated primary mouse corneo-limbal epithelial cells (CLECs) (n = 6) was examined using morphological and functional assays.

RESULTS

Whilst 0.2% BAC induced severe corneal epithelial defects, 0.1% BAC dispensed once daily over 7 days, induced punctate fluorescein staining without detriment to corneal smoothness. Histochemical staining revealed disorganized basal corneal epithelial cells with enlarged cytoplasmic halos. Furthermore, PAS⁺ goblet cells were decreased. BAC treatment also modulated K14 expression and distribution within the limbus. In cultured CLEC, BAC triggered cell contraction and vacuolation, increased LDH release and elevated cell necrosis by 4.1-fold. Concentrations of BAC as low as 0.0001% decreased colony formation.

CONCLUSIONS

This study describes how exposing C57BL/6 mice to BAC induce some clinicopathological features of DED seen in humans, and therefore provides the foundations to explore the consequences on the ocular surface, particularly on limbal epithelia and its' stem cells.

Preservative-free versus preserved brimonidine %0.15 preparations in the treatment of glaucoma and ocular hypertension: short term evaluation of efficacy, safety, and potential advantages

Purpose: To compare the efficacy, safety, and potential advantages of the preservative-free versus preserved brimonidine %0.15 preparations in patients with primer open-angle glaucoma (POAG) or ocular hypertension (OHT).Methods: Forty-two eyes of the 21 treatment-naive patients with POAG or OHT were enrolled in this study. Eyes were randomly assigned to receive brimonidine-purite 0.15% or preservative-free brimonidine 0.15% two times daily. Efficacy of the two eye drops was assessed by measuring the intraocular pressure (IOP) at 9-10 am at baseline and week 4. Safety and potential advantages of the drops were evaluated at weeks 4 in terms of ocular symptoms and tear parameters. Ocular symptom values of the patients were evaluated with a scale of 0-4 (0 = no discomfort and 4 = severe discomfort).Results: Both of the brimonidine tartrate formulations resulted in statistically similar IOP reduction (preserved formulation; -5.2 mmHg [22.9% reduction] preservative-free formulation; -5.7 mmHg [24.1% reduction], p = 0.37). It was found that brimonidine tartrate formulations with and without topical preservatives did not produce a statistically significant difference in pain, stinging, and blurred vision at the upon instillation (p > 0.05). However, the burning sensation was significantly higher in the preservative-free formulation at the first instillation compared to the preserved formulation (p = 0.01). Also, there was no statistically significant difference between the two formulations in terms of symptoms (itching, burning, tearing, stinging, and photophobia) and tear parameters during the day (p > 0.05).Conclusions: Although topical preservative-free brimonidine tartrate treated eyes had a more burning sensation at the first drop, the two formulations were similar in terms of ocular tolerability in the short term period. Also, both formulations were found to reduce IOP at a similar rate.

Tear neuromediators in eyes on chronic topical antiglaucoma therapy with and without BAK preservatives

PURPOSE

To evaluate tear neuropeptides (NPs) (vasoactive intestinal peptide (VIP), neuropeptide Y (NPY), calcitonin gene-related peptide (CGRP), substance P (SP), nerve growth factor (NGF)) in chronic ocular topical hypotensive therapy with and without benzalkonium chloride (BAK) preservative.

METHODS

A comparative, open label, cross-sectional study of patients using antiglaucoma medications for >6 months with BAK (group I), without BAK (group II) and controls was done. Tear NPs (ELISA), ocular surface evaluation tests (tear breakup time (TBUT), Schirmer's test, corneal and conjunctival staining score) and confocal central corneal subbasal nerve fibre layer (SBNFL) imaging was done.

RESULTS

Of 153 eyes evaluated, group 1 (82 eyes (41 patients; mean age 48±14.5 years)) and group 2 (71 eyes (36 patients; mean age 43.11±15 years)) were on therapy for a mean duration of 10.05±2.0 and 9.67±2.3 months, respectively. Tear analysis showed elevated SP and NGF (p<0.01); decreased CGRP (p=0.03), VIP and NPY (p<0.01) compared with controls (n=30, mean age 29.33±5.7 years). Tear NP levels (SP (p=0.1), NGF (p=0.33), CGRP (p=1), VIP (p=0.87), NPY (p=0.83)) and SBNFL (p=0.09) were comparable in both groups. There was no correlation seen between tear NP levels and clinical tests and SBNFL.

CONCLUSION

Our study analysis points towards altered tear NP levels in eyes on chronic topical hypotensive therapy in comparison with controls with no significant difference in tear NP levels and central corneal SBNFL density between the BAK preservative and BAK-free antiglaucoma therapy.

Histopathologic Analysis of Conjunctival Lymphoproliferative Disease After Topical Brimonidine Use

Purpose: To describe of histopathological findings of conjunctival lymphoproliferative disease (CLD) after topical brimonidine use. Methods: This is a retrospective medical record review study, including histopathologic description. We reviewed the medical records of 208 patients (415 eyes) who were diagnosed with glaucoma and who were treated with topical brimonidine only for a minimum of 6 months. Of these, the medical records of 19 patients with suspected CLD clinical features were reviewed in detail. When CLD was suspected due to administration of brimonidine, histopathological analysis was performed by biopsy of these lesions. In addition, immunohistochemical staining was performed to analyze lymphocyte markers in some pathological tissues. Results: Nineteen patients had suspected CLD without definite irritative symptoms. Diffuse elevated (11 patients) or follicular lesion (8 patients) of salmon pink appearance was observed in inferior palpebral conjunctiva. Among these patients, 5 patients who agreed to conjunctival biopsy had histopathological findings of CLD such as reactive lymphoid hyperplasia (LH) (2 cases) or atypical LH (2 cases). The mean duration of brimonidine use was 29.00 ± 20.25 months (6-76 months). And follow-up period after discontinuation of brimonidine was 27.93 ± 11.87 months (12-58 months). At the last visit, complete resolution of the lesion was seen in 13 patients, and partial improvement was observed in 6 patients. Conclusions: We found 4 cases of CLD following long-term administration of brimonidine. However, large-scale additional studies should be performed to establish causality, to determine whether these novel side effects were caused by long-term brimonidine treatment.

The use of preservatives in dry eye drops

Topical ocular preparations are widely recommended by health care professionals, or chosen by patients, to help manage dry eye disease (DED). The chronic and progressive nature of DED may result in the administration of topical products several times a day, over a period of many years. Given DED is a condition that by definition affects the ocular surface, it is important to understand how the repeated use of eye drops may impact the ocular surface, influence clinical signs, affect symptoms, and impact the overall disease process of dry eye. The component in topical preparations with the greatest potential to adversely affect the ocular surface is the preservative. This paper reviews the literature in relation to the use of preservatives in formulations for dry eye. The ocular effects of benzalkonium chloride (BAK) are summarised and compared to the performance of alternative preservatives and preservative-free formulations. Use of preserved and preservative-free drops in relation to the management of varying stages of DED is discussed.

Effect of Topical Prostaglandin F2α Analogs on Selected Oxidative Stress Parameters in the Tear Film

Background and Objectives: Topically administered antiglaucoma medications, especially those containing benzalkonium chloride (BAC), may cause local adverse effects and compromise ocular surface. The aim of the study was to assess the effect of topical prostaglandin F2α analogs (PGAs): preservative-free latanoprost, BAC-preserved latanoprost, preservative-free tafluprost, and BAC-preserved bimatoprost, on selected oxidative stress parameters in the tear film. Materials and Methods: The patients were divided into five groups: group C (n = 25) control group—subjects who did not use topical antiglaucoma medications, group L (n = 22)—patients using topical preservative-free latanoprost, group L+BAC (n = 25)—patients using topical BAC-preserved latanoprost, group T (n = 19)—patients using topical preservative-free tafluprost, and group B+BAC (n = 17)—patients using topical BAC-preserved bimatoprost. The oxidative stress markers in the tear film samples were evaluated: total protein (TP) concentration, advanced oxidation protein products (AOPP) content, total sulfhydryl (-SH) groups content, the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), as well as Total Oxidant Status (TOS), Total Antioxidant Response (TAR), and Oxidative Stress Index (OSI). Results: The TP concentrations in the groups L, L+BAC, and B+BAC were statistically significantly higher in comparison with group C. The SOD and CAT activities in the groups L+BAC and B+BAC were statistically significantly higher when compared to group C. As compared to group C, AOPP and TOS were statistically significantly higher in all the study groups. OSI was found to be statistically significantly higher in the groups L+BAC, T, and B+BAC in comparison with group C. Conclusion: Use of topical PGAs by the patients with ocular hypertension or primary open-angle glaucoma is associated with increased oxidative stress in the tear film which is additionally exacerbated by the presence of BAC in the formulation.

Noninferiority of Preservative-free Versus BAK-preserved Latanoprost-timolol Fixed Combination Eye Drops in Patients With Open-angle Glaucoma or Ocular Hypertension

PRéCIS:: Noninferiority of efficacy was demonstrated for a preservative-free latanoprost-timolol fixed combination compared with a BAK-containing formulation at 84 days after treatment in patients with open-angle glaucoma or ocular hypertension.

PURPOSE

The purpose of this study was to compare the effect on intraocular pressure and safety of preservative-free latanoprost-timolol fixed combination (T2347) to benzalkonium chloride-preserved latanoprost-timolol fixed combination in patients with open-angle glaucoma or ocular hypertension.

METHODS

Phase III, randomized, parallel-group, investigator-masked study in 10 countries. A total of 242 patients aged 18 years or older with open-angle glaucoma or ocular hypertension in both eyes controlled with a preserved latanoprost-timolol fixed combination (15.7±2.4 mm Hg overall before inclusion) were randomized at day 0 with no washout period to receive the preservative-free alternative T2347 (N=127) or remain on the preserved comparator (N=115) for 84 days. Intraocular pressure changes from day 0 were measured at 9:00 am (±1 hour) on day 42 and day 84, and noninferiority of T2347 to the preserved comparator was analyzed statistically at day 84. Safety parameters were also reported.

RESULTS

The mean change in intraocular pressure from baseline to day 84 was -0.49±1.80 mm Hg for preservative-free T2347 and -0.49±2.25 mm Hg for the preserved comparator. These results met the noninferiority limits. Similar results were observed at day 42. There was no difference between groups in the incidence of adverse events or ocular signs. The total ocular symptoms score was better for T2347 than BPLT upon instillation at day 84 (45.9%/44.3%/9.8% of patients with improvement/no change/worsening vs. 33.6%/47.3%/19.1%; P=0.021), reflecting improvements in individual symptoms such as irritation/burning/stinging (P<0.001), and itching (P<0.01) on day 84.

CONCLUSIONS

Preservative-free latanoprost-timolol fixed combination T2347 showed noninferior efficacy compared with the preserved comparator and was well tolerated.

Timolol 0.1% in Glaucomatous Patients: Efficacy, Tolerance, and Quality of Life

Glaucoma is a progressive, chronic optic neuropathy characterized by a typical visual field defects. Four main classes of topical medication are actually available on the market: beta-blockers, prostaglandins, alpha2-agonists, and topical carbonic anhydrase inhibitor to treat intraocular pressure (IOP). The aim of this review is to outline the efficacy of timolol and to evaluate the impact of this treatment on patients' quality of life. Among beta-blockers, timolol is most used at three different concentrations: 0.1%, 0.25%, and 0.5%. While the first one is a gel, the other two products are solution. Timolol has few topical side effects, while it has some important systemic side effects on the cardiac and respiratory systems. The balance between efficacy and safety is always the main aspect to care patients. Because of the less efficacy of timolol 0.1% solution, the possibility to use carbomers as vehicle in the gel drops helped timolol 0.1 to be used in clinics, extending the time contact between the active ingredient and the surface of the cornea. Using preservative-free timolol 0.1 for treatment, IOP was at the same level of the other beta-blockers at higher concentration, but it was better tolerated. Preservative-free treatment improved the quality of life reducing dry-eye like symptoms; furthermore, the presence of an artificial tear in the medication bottle could help adherence. The once daily dosing improves compliance.

Ocular Surface Disease and Glaucoma Medications: A Clinical Approach

OBJECTIVES

Ocular surface disease frequently coexists with glaucoma and may be initiated or exacerbated by topical glaucoma medications. We performed a review of current literature to assess the prevalence, causes, and treatment of ocular surface disease in glaucoma patients, specifically those on topical therapy.

METHODS

A Pubmed database search was conducted. A total of 720 articles published from 1972 to 2018 were found in relation with ocular surface disease, glaucoma, and glaucoma medications. Of these, 102 articles were included in this analysis. We included primary and empirical studies for patients on topical glaucoma medications. Exclusion criteria included case reports, non-English studies, and articles unrelated to the primary subject of this review.

RESULTS

Ocular surface disease among normal and glaucomatous eyes was evaluated based on diagnostic testing including clinical examination and questionnaires to determine visual function and quality of life. Glaucoma medications can be associated with toxicities to the ocular surface, most often due to the nature of the preservative included in the medication; however, the incidence of toxicity can be mitigated by the use of preservative free medications, decreased preservative medications, or treatment of dry eye disease. Treatment of glaucoma with laser trabeculoplasty or minimally invasive glaucoma surgeries that spare the conjunctiva and the cornea may avoid or decrease reliance on topical glaucoma medications, potentially avoiding the initiation or progression of ocular surface disease.

CONCLUSIONS

Recognition and treatment of ocular surface disease in glaucoma patients may improve patient quality of life and medication adherence. This may ultimately improve glaucoma treatment outcomes.

In vitro effects of benzalkonium chloride and prostaglandins on human meibomian gland epithelial cells

PURPOSE

Benzalkonium chloride is the most widely used preservative in ophthalmic topical solutions. The aim of this study was to investigate the influence of BAC as a single substance or as a component of several commercially available ophthalmic solutions on meibomian gland epithelial cells in vitro.

MATERIALS AND METHODS

An immortalized human meibomian gland epithelial cell line (HMGEC) was used and cells were cultured in the absence or presence of fetal bovine serum to assess cell morphology, cell proliferation, cell viability (MTS assay) and impedance sensing (ECIS) after stimulation with BAC. Further, the viability of HMGECs stimulated with BAC-containing and BAC-free bimatoprost, travoprost and latanoprost was evaluated using the MTS assay. Real-time PCR analysis for hyperkeratinization associated genes (cornulin, involucrin) was performed.

RESULTS

In the absence of serum, the proliferation rate of HMGECs decreased starting with 0.1μg/ml BAC. At concentrations of 50μg/ml BAC and higher, cell viability was reduced after 10min exposure with a corresponding change in cell morphology. Toxicity of BAC-containing ophthalmic solutions was greater than that of BAC alone, whereas BAC-free alternative products did not significantly influence cell viability. Confluence, cell-cell contacts and serum-containing medium appeared to facilitate HMGECs survival. Expression rate of involucrin and cornulin declined after exposure to preserved bimatoprost and BAC.

CONCLUSIONS

BAC showed cytotoxic effects on HMGECs starting with a concentration of 0.1μg/ml. The combination of BAC and prostaglandin-analogs might have a synergistic effect which results in higher toxicity than BAC alone. Unpreserved eye drops and eye drops preserved with Polyquaternium-1 are less damaging to HMGECs.

Better tolerance of preservative-free latanoprost compared to preserved glaucoma eye drops: the 12-month real-life FREE study

Background

Lack of efficacy due to bad compliance caused by intolerance issues is the main reason for a change to a better tolerated ocular treatment, such as using preservative-free (PF) eye drops.

Aim

To assess the efficacy and local tolerance after 12 months and patient satisfaction regarding local treatment tolerance and handling at inclusion and after 6 months of PF latanoprost compared to preserved glaucoma eye drops.

Methods

This was an international, prospective, and observational real-life study. Up to three visits, one at inclusion and two follow-up visits (one after 6 and one after 12 months) were planned. Efficacy, local tolerance, and patient satisfaction were the main evaluation criteria.

Results

Data from 721 patients were available for the statistical analysis. Overall, 64.8% (467/721) of patients switched treatment before inclusion: 62.2% in the preserved and 68.9% in the PF latanoprost group. IOP values were similar between PF latanoprost and preserved eye drops and remained stable at all visits. Ocular signs and symptoms improved after switching to PF latanoprost; the prevalence of conjunctival hyperemia was significantly lower (P=0.0015) at both follow-up visits. At follow-up visit 1, 49.5% of the patients who switched to PF latanoprost decreased or stopped the use of artificial tears. Satisfaction regarding tolerance in patients using PF latanoprost improved significantly after the switch from preserved eye drops to PF latanoprost (88.9% and 42.5%, respectively, P<0.0001).

Conclusion

This first real-life study showed that PF latanoprost was as efficacious but better tolerated than preserved eye drops over a sustained period of 12 months, while providing a significantly higher patient satisfaction and potentially allowing improvement in the patient’s daily life.

Preservative-Free Prostaglandin Analogs and Prostaglandin/Timolol Fixed Combinations in the Treatment of Glaucoma: Efficacy, Safety and Potential Advantages

Glaucoma therapy-related ocular surface disease (OSD) is a serious pathology with a broad spectrum of insidious clinical presentations and complex pathogenesis that undermines long-term glaucoma care. Preservatives, especially benzalkonium chloride (BAK), contained in topical intraocular pressure-lowering medications frequently cause or aggravate OSD in glaucoma. Management of these patients is challenging, and to date often empirical due to the scarcity of controlled long-term clinical trials. Most of the available data are extracted from case series and retrospective analysis. Preservative-free prostaglandins and prostaglandin/timolol fixed combinations are novel options developed to remove the harmful impact of preservatives, especially BAK, upon ocular tissues. Based on what is currently known on the value of preservative-free antiglaucoma therapies it is tempting to speculate how these new therapies may affect the future medical management of all glaucoma patients. This article provides a comprehensive and critical review of the current literature on preservative-free prostaglandins and preservative-free prostaglandin/timolol fixed combinations.

Vision-related quality of life in Pakistani subjects with early or moderate glaucoma

Background

The aim of this study was to report the vision-related quality of life (QoL) in Pakistani subjects with early or moderate glaucoma.

Methods

This case control study was conducted at Al-Shifa Trust Eye Hospital, Pakistan, from 1 January 2014 to 31 December 2015. All the patients having early or moderate glaucoma, with a disease duration of at least 6 mo, and presenting during the study period, were included. Subjects in the control group were recruited from the hospital volunteer staff, spouses and friends of patients. QoL assessment was done using the NEIVFQ25 questionnaire translated into the Urdu language. A two-tailed t-test was used to test the significance of difference between the mean QoL scores and a p-value of ≤0.05 was considered significant. Multiple linear regression was carried out to assess the predictors of QoL scores.

Results

A total of 698 participants were enrolled, including 247 cases and 451 controls. The mean QoL score was higher in controls 81.31 (mean=81.31, SD=26.33) than in cases (mean=53.89, SD=30.32), p<0.001. The lowest NEIVFQ-25 scores for glaucoma patients were for mental health (mean=23.88, SD=28.80) followed by general vision (mean=27.73, SD=29.74). The difference in all the mean subscale scores of two groups was statistically significant (p<0.001).

Conclusion

QoL scores are significantly reduced in Pakistani glaucoma patients with early and moderate glaucoma, with more pronounced effect on mental health and general vision.

Objective ocular surface tolerance in patients with glaucoma treated with topical preserved or unpreserved prostaglandin analogues

Purpose:

Preservatives in glaucoma medications have been associated with ocular toxicity. We compared ocular signs and symptoms in patients with open-angle glaucoma or ocular hypertension treated in monotherapy with preserved or preservative-free prostaglandin analogues.

Methods:

Observational cross-sectional clinical study in real life. 82 patients treated for at least 6 months with prostaglandin analogue were assessed for intraocular pressure, ocular symptoms and ocular signs including conjunctival hyperaemia, tear break-up time and tear meniscus height measured using objective and non-invasive methods (OCULUS Keratograph 5M). Patients presenting with symptoms of ocular toxicity with preserved prostaglandin analogues were switched to preservative-free latanoprost, and a second assessment was processed 6 months after.

Results:

At inclusion, 30 (36.6%) patients were treated with preservative-free latanoprost, 25 (30.5%) with preserved latanoprost, 16 (19.5%) with preserved travoprost and 11 (13.4%) with preserved bimatoprost. Patients treated with preservative-free latanoprost reported significantly less ocular symptoms upon instillation (mainly burning) and between instillations than patients treated with preserved prostaglandin analogues. The mean conjunctival hyperaemia (limbal + bulbar) was significantly lower with preservative-free latanoprost (2.08 ± 0.55) compared to preserved latanoprost (2.50 ± 0.7, p = 0.0085), preserved travoprost (2.67 ± 0.82, p = 0.0083) and preserved bimatoprost (2.68 ± 0.67, p = 0.0041). There were no relevant between-group differences in mean tear meniscus height and break-up time. Ocular symptoms and conjunctival hyperaemia improved when preserved prostaglandin analogues were switched to preservative-free latanoprost for 6 months while intraocular pressure reduction was maintained.

Conclusion:

Overall, this study suggests a better subjective and objective ocular tolerance when patients were treated with preservative-free latanoprost than with other preserved prostaglandin analogues monotherapy. Switching to preservative-free latanoprost maintained intraocular pressure at the same level as preservative prostaglandin analogue, but improved ocular surface tolerance.

Cytokine expression in tears of patients with glaucoma or dry eye disease: A prospective, observational cohort study

BACKGROUND

The aim of this study was to assess the expression of cytokines/chemokines in tears from patients with non-advanced primary open-angle glaucoma and patients with non-severe dry eye disease versus healthy controls.

METHODS

This prospective, observational cohort study enrolled patients with confirmed or suspected non-advanced primary open-angle glaucoma who received any prostaglandin analogue monotherapy for longer than 6 months, patients with non-severe dry eye disease, and healthy controls. Expression of interleukin-1β, interleukin-2, interleukin-4, interleukin-5, interleukin-6, interleukin-8, interleukin-10, and interleukin-12; tumor necrosis factor α; vascular endothelial growth factor; granulocyte-macrophage colony-stimulating factor; and interferon γ was assessed.

RESULTS

107 participants were enrolled (primary open-angle glaucoma, n = 41; dry eye disease, n = 30; and healthy controls, n = 36). Compared with healthy controls, interleukin-6 was significantly higher (p = 0.0001) in patients with primary open-angle glaucoma and interleukin-1β (p = 0.0144), interleukin-6 (p < 0.0001), and interleukin-10 (p = 0.0392) were higher in patients with dry eye disease. Compared with patients with dry eye disease, patients with primary open-angle glaucoma had significantly lower levels of interleukin-4 (21.79 vs 20.18 pg/mL; p = 0.0012) and significantly higher levels of vascular endothelial growth factor (367.75 vs 609.28 pg/mL; p = 0.0058), tumor necrosis factor α (14.27 vs 17.93 pg/mL; p = 0.0048), and interleukin-6 (17.95 vs 27.48 pg/mL; p = 0.0145). In patients with primary open-angle glaucoma, interleukin-1β expression (p = 0.0011) was lower than in those who received intraocular pressure-lowering eye drops without preservatives compared with those who received eye drops with preservatives.

CONCLUSION

Different cytokine/chemokine expression profiles in tears of patients with primary open-angle glaucoma and dry eye disease strongly suggest the involvement of a variety of signaling pathways in the pathogenesis of these ophthalmic processes.

Preservatives in glaucoma medication

Preservatives continue to be in widespread use in ophthalmic medications due to the convenience they provide, regulatory requirements and the higher cost of alternatives. Benzalkonium chloride (BAK) remains the most commonly used preservative but there is a trend towards the use of preservative-free (PF) drops for glaucoma, although at a higher price. An extensive body of literature explores BAK toxicity on ocular structures in animal and laboratory studies (in vitro and in vivo). Non-randomised controlled studies have provided some supporting evidence of its toxicity in patients, especially in those with pre-existing ocular surface disease (OSD) or on multiple medications. However, there have been very few randomised controlled trials that compare the same medication with and without BAK preservative. Several of these trials have never been published in any peer reviewed journals. Notwithstanding, those that have been published, have not demonstrated any clear benefits of the BAK-free formulations. Short duration and exclusion of those with OSD are limitations of these studies. There is a lack of evidence of clinically significant harm from a small number of BAK preserved drops in patients without OSD. This means that generally more expensive PF glaucoma medications should only be recommended for those on poly pharmacy or those with OSD but are not necessarily required for all patients.

Ocular surface status in glaucoma and ocular hypertension patients with existing corneal disorders switched from latanoprost 0.005% to tafluprost 0.0015%: comparison of two prostaglandin analogues with different concentrations of benzalkonium chloride

IMPORTANCE

Glaucoma treatment has often been associated with adverse side-effects from preservatives that are included in the used eye drops.

BACKGROUND

To evaluate changes in the ocular surface and the presence of prostaglandin-induced corneal disorders after being switched from latanoprost 0.005% to low preservative tafluprost 0.0015% ophthalmic solution.

DESIGN

Single centre, prospective study.

PARTICIPANTS

Patients with primary open-angle glaucoma or ocular hypertension that had received treatment with once daily latanoprost 0.005% ophthalmic solution for control of intraocular pressure (IOP) for 3 months, with a score of above 1 on the National Eye Institute (NEI) ocular surface staining scale.

METHODS

Following the ≥3 month latanoprost treatment period, patients were switched to once daily low preservative tafluprost 0.0015% ophthalmic solution. Patients were followed for a minimum of 3 months.

MAIN OUTCOME MEASURES

Ocular surface changes were assessed by fluorescein staining score (NEI scale). Additional evaluations included tear break-up time, hyperaemia score, subjective symptoms, changes in intraocular pressure and presence of adverse reactions.

RESULTS

Out of 59 patients enrolled, 51 were included in the final analysis. Fluorescein staining scores at baseline, prior to treatment switch, were 6.9 ± 3.1 and 3.3 ± 2.7 at the end of the study period (change in scores was -3.6 ± 2.2 [P < 0.001]). At last follow-up, significant improvements were observed in tear break-up time, hyperaemia score and subjective symptoms (all P < 0.05).

CONCLUSIONS AND RELEVANCE

The clinical signs of ocular surface disease and subjective symptoms of dry eyes improved following the switch to low preservative tafluprost and demonstrated comparable IOP lowering effectiveness.

Reduction in Ocular Hypotensive Eyedrops by Ab Interno Trabeculotomy Improves Not Only Ocular Surface Condition But Also Quality of Vision

Purpose

To investigate the effect of ab interno trabeculotomy using the Trabectome surgical system on tear film stability and functional visual acuity (FVA).

Patients and Methods

Adult glaucoma patients who underwent Trabectome surgery alone or Trabectome surgery combined with phacoemulsification with intraocular lens insertion were included in this study. Corneal epithelial defects, tear film breakup time (TBUT), tear meniscus height, tear film spreading grade, tear interferometry grade, and FVA were assessed before and after surgery in addition to routine ophthalmic examinations. Changes in ocular surface conditions and visual acuity as a result of the Trabectome surgery were investigated.

Results

Thirty eyes of 22 patients with a mean age of 72.2 ± 7.9 years, including 8 males and 14 females, were enrolled. The Trabectome surgery significantly reduced the intraocular pressure (IOP) from 20.3 ± 5.2 to 15.0 ± 3.3 mmHg (P < 0.001) and the number of different types of ocular hypotensive eyedrops used from 3.2 ± 0.7 to 1.1 ± 0.7 types (P < 0.001). The surgery significantly improved corneal epithelial defects, the tear spreading grade, the tear interferometry grade, and FVA. The surgery also improved the visual maintenance ratio among all enrolled patients, including those who underwent Trabectome surgery only.

Conclusion

Trabectome surgery may be beneficial not only for IOP reduction but also for improving ocular surface conditions and FVA.

Dry eye disease and oxidative stress

Dry eye, an age-related condition, is a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbance and tear film instability. Environmental factors are also often implicated in dry eye including exposure to pollutants, ultraviolet (UV) radiation and ozone as well as the chronic use of preserved eyedrops such as in the treatment of glaucoma. These factors increase oxidative stress and ocular surface inflammation. Here, we reviewed the cellular, animal and clinical studies that point to the role of oxidative stress in dry eye disease. The biomarkers used to indicate oxidative damage in ocular surface tissues include 8-hydroxy-2 deoxyguanosine (8-OHdG), 4-hydroxynonenal (HNE) and malondialdehyde (MDD). Antioxidative defences in the ocular surface occur in the form of tear proteins such as lactoferrin and S100A proteins, and enzymes such as superoxide dismutase (SOD), peroxidase, catalase and mitochondrial oxidative enzymes. An imbalance between the level of reactive oxygen species (ROS) and the action of protective enzymes will lead to oxidative damage, and possibly inflammation. A small number of interventional studies suggest that oxidative stress may be directly targeted in topical therapy of dry eye treatment. For example, in vitro studies suggest that L-carnitine and pterostilbene, a blueberry component may reduce oxidative stress, and in animal studies, alpha-lipoic acid (ALP) and selenoprotein P may be helpful. Examples of treatments used in clinical trials include vitamin B12 eyedrops and iodide iontophoresis. With recent emphasis on ageing medicine and preventive holistic health, as well as the role of environmental science, research on oxidative stress in the ocular surface is likely to have increasing impact in the coming years.

Evaluating the novel application of cyclosporine 0.1% in ocular surface disease

INTRODUCTION

Ocular surface disease (OSD) is a highly prevalent symptomatic condition caused by dry eye disease (DED), intrinsic, environmental, or iatrogenic causes. It affects patient's visual function and quality of life. Its pathophysiology is centered on tear hyperosmolarity, inflammation, and epithelial damage. Current management is suboptimal and includes artificial tear supplementation and short-term use of topical steroids in severe cases. The recent approval of cyclosporine 0.1% has transformed management strategies of severe DED and moderate-to-severe OSD. Areas covered: This review summarizes existing information on the efficacy, safety, and tolerability of the new cyclosporine 0.1% formulation. Expert opinion: Topical cyclosporine A 0.1% represents a promising, novel medication for the management of DED, Meibomian gland dysfunction, and inflammatory OSD. It is primarily beneficial for those patients requiring topical immunomodulatory therapy. This topical formulation also has the potential to meaningfully improve the management of moderate-to-severe glaucoma therapy-related OSD. Currently there is limited published clinical data concerning the efficacy of topical cyclosporine. There are, however, theoretical advantages when comparing this cyclosporine formulation with other established commercial preparations. Future research is needed to delineate the precise role and value of this medication.

Effects of 20% Human Serum on Corneal Epithelial Toxicity Induced by Benzalkonium Chloride: In Vitro and Clinical Studies

PURPOSE

Benzalkonium chloride (BAK), the most commonly used preservative in ophthalmic solutions, is known to cause toxicity in the corneal epithelium. In this study, we investigated the effects of 20% human serum in cultures of BAK-damaged human corneal epithelial cells (hCECs) and in patients with toxic corneal epitheliopathy induced by BAK-containing eye drops.

METHODS

hCECs were exposed to various concentrations of BAK (0%, 0.002%, 0.02%, and 0.2%) in the presence or absence of 20% human serum. After 24 hours, the metabolic activity, proliferation, apoptosis, and proinflammatory cytokine expression were evaluated in the cells. Also, cell migration was assessed using a scratch test. In the clinical study, 24 patients with toxic corneal epitheliopathy secondary to BAK-containing antiglaucoma eye drops were treated with topical application of 20% autologous serum, and corneal epithelial integrity was evaluated.

RESULTS

BAK induced cytotoxicity in hCECs by inhibiting the metabolic activity, proliferation, and migration and by increasing apoptosis in a concentration-dependent manner. The level of proinflammatory cytokine IL-8 was elevated in BAK-treated cells. Addition of 20% human serum to the cultures significantly promoted the cell metabolic activity, proliferation, and migration while markedly reducing apoptosis. In line with the in vitro results, corneal punctate epithelial erosions were decreased from a National Eye Institute scale score of 4.2 ± 2.1 to 1.3 ± 1.7 in 20 of 24 patients (84%) after treatment with 20% autologous serum.

CONCLUSIONS

Data demonstrate that 20% human serum is effective in treating BAK-induced cytotoxicity in hCECs and provides a basis for using 20% autologous serum for patients with preservative-induced corneal epitheliopathy.

A Phase III Randomized Clinical Trial of a 0.5% Timolol + 0.2% Brimonidine + 2.0% Dorzolamide Fixed Combination, Preservative-Free Ophthalmic Solution vs. 0.5% Timolol + 0.2% Brimonidine + 2.0% Dorzolamide Fixed Combination in Patients with Controlled Primary Open-Angle Glaucoma

Introduction

The aim of this prospective crossover study was to evaluate the non-inferiority of PRO-122 (a preservative-free fixed combination) compared with 0.5% timolol + 0.2% brimonidine + 2.0% dorzolamide fixed combination (KOF) by evaluating its efficacy, tolerability and safety in subjects with controlled primary open-angle glaucoma (POAG) previously treated with KOF for at least 2 months.

Methods

In a prospective, crossover, randomized, double-masked multicenter study, patients previously treated with KOF were randomly assigned to receive either PRO-122 or KOF for 30 days. On day 31, the A sequence changed to KOF, while the B sequence received PRO-122. All patients remained in the protocol for 30 additional days for a total of 60 days. The main efficacy endpoint was maintaining the controlled intraocular pressure (IOP). The safety and tolerability of both products were assessed by the presence of adverse events (AEs), ocular findings, a questionnaire on ocular comfort and the VF-14 index.

Results

A total of 51 patients participated. After application of PRO-122 twice a day, its efficacy was demonstrated through maintenance of the controlled IOP in patients previously controlled with KOF. The crossover between PRO-122 and KOF and vice versa, after 30 days of use, did not affect IOP control. PRO-122 was shown not to be inferior to KOF in maintaining IOP at control levels. The safety of both drugs is similar, as neither presented drug-related AEs or differences regarding safety issues. The tolerability of the two medications—evaluated by ocular findings, the questionnaire on ocular comfort and the VF-14 index—was also determined to be similar.

Conclusions

The controlled IOP in patients with controlled POAG treated with PRO-122 was maintained both in relation to the initial controlled IOP of the study and when compared with KOF in the B sequence. Finally, the treatment with PRO-122 demonstrated similar safety and tolerability to KOF.

Funding

Laboratorios Sophia, S.A. de C.V. (Zapopan, Jalisco, México).

Trial Registration

ClinicalTrials.gov identifier: NCT03257813 (registered retrospectively).

Glaucoma therapy: preservative-free for all?

Preservatives used in topical glaucoma medications have a plethora of well-described toxic effects on the ocular surface. Such ocular toxicity is manifest clinically as ocular surface disease (OSD) and has been confirmed in epidemiologic, prospective clinical trials and studies in which patients are switched from preservative-added to preservative-free topical therapy. Such toxicity has implications not only for tolerability, but also for adherence and persistence with therapy that is known to be poor in glaucoma. Glaucoma medication is now widely available in preservative-free formulations, and the question arises as to which patients should receive preservative-free glaucoma therapy in preference to preservative-added medication. A case can be made for several subpopulations of patients who might particularly benefit from preservative-free medication: patients with existing OSD, older patients, younger adult patients, female patients, pediatric and juvenile patients, patients who work in air-conditioned environments or who use electronic screens frequently, patients with medical risk factors for OSD, patients in whom trabecular surgery may become indicated in the future, contact lens users, perhaps patients with Asian ethnicity and patients with severe or treatment-refractory glaucoma. Whilst arguments could be made for selecting patients for preservative-free medication on the basis of their existing risk of OSD, collectively, these patients form a significant proportion of the glaucoma patient population as a whole and, in the absence of any cost premium or positive indication for preservative-added medication, preservative-free glaucoma medication for all patients seems an appropriate strategy.

Barriers to Glaucoma Medication Compliance Among Veterans: Dry Eye Symptoms and Anxiety Disorders

OBJECTIVE

To identify barriers to compliance of medical treatment for glaucoma among veterans.

METHODS

Patients with glaucoma from the Miami Veterans Affairs Eye Clinic (n=74) filled out a 63-question survey regarding dry eye symptoms, concurrent systemic disease, and medications. The association between glaucoma medical compliance was defined as self-reported adherence to drop regimens greater than 75% of the time.

RESULTS

Eighty percent of veterans (n=59) reported compliance with glaucoma therapy. Dry eye symptoms (as defined by Dry Eye Questionnaire 5 score ≥6) were reported by 39% (n=29), and their presence was associated with decreased compliance (63% vs. 89%, P=0.007). Anxiety and posttraumatic stress syndrome (PTSD) were also associated with significant noncompliance (64% vs. 83%, P=0.05 and 58% vs. 84%, P=0.02, respectively). Other studied factors including demographics, depression (P=0.11), and glaucoma regimens did not play a significant role in glaucoma medication compliance.

CONCLUSIONS

Dry eye symptoms, PTSD, and anxiety were associated with decreased compliance to medical treatment of glaucoma. Identifying and treating underlying ocular surface disease and anxiety disorders may lead to increased adherence to glaucoma treatment.

Eye Drop Dispenser Type and Medication Possession Ratio in Patients With Glaucoma: Single-Use Containers Versus Multiple-Use Bottles

PURPOSE

To determine whether the consumption of topical glaucoma medication is influenced by the type of eye drop dispenser.

DESIGN

Retrospective cohort study.

METHODS

We examined 366 patients with open-angle glaucoma or ocular hypertension who were bilaterally treated with 0.0015% tafluprost or 2% dorzolamide/0.5% timolol fixed combination (DTFC). The patients were grouped by the type of dispenser and content of eye drops used: (1) tafluprost in bottles (T-Bottle group); (2) tafluprost in unit-dose pipettes (T-Unit group); (3) DTFC in bottles (C-Bottle group); and (4) DTFC in unit-dose pipettes (C-Unit group). We evaluated the medication possession ratio (MPR) among groups, and factors associated with over-consumption (MPR > 1.2) or under-consumption (MPR < 0.8) in multinomial logistic regression.

RESULTS

The mean MPR was 1.49 (range, 0.69-2.91) in the T-Bottle group, 0.91 (range, 0.32-1.27) in the T-Unit group, 1.25 (range, 0.51-2.60) in the C-Bottle group, and 0.96 (range, 0.36-1.60) in the C-Unit group. The Bottle groups demonstrated higher mean values and wider ranges of MPR compared to the Unit groups. The MPR interval at which the largest number of patients were found was 1.0-1.4 in the Bottle groups and 0.8-1.2 in the Unit groups. Bottle-type dispenser (odds ratio [OR] 64.02), tafluprost medication (OR 2.84), and older age (OR 1.03) were associated with over-consumption, whereas no factor was correlated with under-consumption.

CONCLUSIONS

The type of eye drop dispenser affects the consumption of glaucoma medication. Physicians should consider the type of eye drop dispenser when assessing glaucoma medication adherence.

Switch from BAK-preserved to preservative-free latanoprost decreases anterior chamber flare in POAG patients

PURPOSE

To validate the hypothesis that BAK induces low-grade inflammation in the anterior chamber, we designed a study to investigate whether switching from BAK-preserved to preservative-free latanoprost in patients with primary open-angle glaucoma (POAG) would reduce the flare levels.

PATIENTS

Forty-one eyes of twenty-two patients with primary open-angle glaucoma treated with BAK-preserved latanoprost for at least 6 months as monotherapy were included. Exclusion criteria included any use of topical eye drops other than latanoprost, pseudoexfoliation and pigment dispersion glaucoma, wearing of contact lenses and intraocular surgery in the past year.

METHODS

At the start of the study, we measured baseline flare values. We then switched all patients to preservative-free latanoprost. After 1, 2, and 3 months, a routine ophthalmological examination was performed and flare measurement repeated.

RESULTS

Thirty-three eyes were followed up throughout the entire 3-month period. One month after the switch to preservative-free latanoprost, a statistically significant mean drop in flare of - 0.96 ph/ms (P = 0.025) was observed. Mean flare decreased further by - 1.31 ph/ms (P = 0.0027) after 2 months and by - 1.25 ph/ms (P = 0.0041) after 3 months.

CONCLUSION

The switch from BAK-preserved to preservative-free latanoprost induced a statistically significant reduction in mean flare value. Whereas our previous study showed an increase in flare when initiating treatment with BAK-preserved eye drops, this study shows a decrease in flare upon cessation of BAK-preserved drugs. The combined evidence from the two studies strongly suggests that in humans BAK exerts its effects not only on the ocular surface, but also at the level of the anterior chamber.

Multidose Preservative Free Eyedrops by Selective Removal of Benzalkonium Chloride from Ocular Formulations

PURPOSE

About 70% of eye drops contain benzalkonium chloride (BAK) to maintain sterility. BAK is an effective preservative but it can cause irritation and toxicity. We propose to mitigate ocular toxicity without compromising sterility by incorporating a filter into an eye drop bottle to selectively remove BAK during the process of drop instillation.

METHODS

The filter is a packed bed of particles made from poly(2-hydroxyethyl methacrylate) (pHEMA), which is a common ophthalmic material. We showed that pHEMA particle prepared by using ethoxylated trimethylolpropane triacrylate as crosslinker can be incorporated into a modified eyedrop bottle tip to selectively remove the preservative as the formulation is squeezed out of the bottle. Hydraulic permeability of the plug is measured to determine the resistance to eye drop squeezing, and % removal of BAK and drugs are determined.

RESULTS

The modified tip has a hydraulic permeability of about 2 Darcy, which allows eyedrops formulations to flow through without excessive resistance. The tip is designed such that the patients can create an eyedrop of solution of 1-10 cP viscosity in 4 s with a nominal pressure. During this short contact time, the packed particles removed nearly 100% of benzalkonium chloride (BAK) from a 15 mL, 0.012% BAK solution but have only minimal impact on the concentration of contained active components.

CONCLUSION

Our novel design can eliminate the preservative induced toxicity from eye drops thereby impacting hundreds of millions of patients with chronic ophthalmic diseases like glaucoma and dry eyes.

Micro-invasive glaucoma surgery (MIGS): a review of surgical procedures using stents

Over the last decade several novel surgical treatment options and devices for glaucoma have been developed. All these developments aim to cause as little trauma as possible to the eye, to safely, effectively, and sustainably reduce intraocular pressure (IOP), to produce reproducible results, and to be easy to adopt. The term “micro-invasive glaucoma surgery (MIGS)” was used for summarizing all these procedures. Currently MIGS is gaining more and more interest and popularity. The possible reduction of the number of glaucoma medications, the ab interno approach without damaging the conjunctival tissue, and the probably safer procedures compared to incisional surgical methods may explain the increased interest in MIGS. The use of glaucoma drainage implants for lowering IOP in difficult-to-treat patients has been established for a long time, however, a variety of new glaucoma micro-stents are being manufactured by using various materials and are available to increase aqueous outflow via different pathways. This review summarizes published results of randomized clinical studies and extensive case report series on these devices, including Schlemm’s canal stents (iStent^®, iStent^® inject, Hydrus), suprachoroidal stents (CyPass^®, iStent^® Supra), and subconjunctival stents (XEN). The article summarizes the findings of published material on efficacy and safety for each of these approaches.

Revision of trabeculectomy filtering blebs with mitomycin C: Long term results

Aim:

The aim of the study is to assess the outcomes of transconjunctival mitomycin C (MMC)-augmented revision in eyes with failed trabeculectomy.

Materials and Methods:

This is a retrospective, noncomparative case series. One hundred and twenty-one eyes of 113 consecutive glaucoma patients with previously failed trabeculectomy who underwent transconjunctival revision with at least 12 months of follow-up were initially included in the study. The success was determined on the basis of intraocular pressure (IOP) alone. The main outcome measures were IOP, best-corrected distance visual acuity, complications, bleb appearance, lens status, visual field progression, and time between primary trabeculectomy and MMC revision. The main purpose of the study was to determine the efficacy of a single MMC-augmented needle revision.

Results:

Mean follow-up was 2.3 years. Twelve months after revision, IOP had declined from 26.1 ± 8.4 mmHg to 14.1 ± 4.8 mmHg (P < 0.05) and remained 16.0 ± 5.6 mmHg at 24 months, 15.7 ± 5.8 mmHg at 48 months, and 15.2 ± 4.0 mmHg at 60 months. Complete success was achieved in 53% of cases, 84% achieved qualified success, and 16% were classified as failures 12 months after revision. Early complications developed in 45 of the initial 121 eyes (37.2%).

Conclusions:

Transconjunctival MMC-augmented revision appears to be a safe and useful tool in reducing IOP and re-establishing filtration after trabeculectomy failure. This simple procedure has a high rate of success and helps avoid other surgical interventions which are more destructive for the conjunctiva.

TFOS DEWS II iatrogenic report

Dry eye can be caused by a variety of iatrogenic interventions. The increasing number of patients looking for eye care or cosmetic procedures involving the eyes, together with a better understanding of the pathophysiological mechanisms of dry eye disease (DED), have led to the need for a specific report about iatrogenic dry eye within the TFOS DEWS II. Topical medications can cause DED due to their allergic, toxic and immuno-inflammatory effects on the ocular surface. Preservatives, such as benzalkonium chloride, may further aggravate DED. A variety of systemic drugs can also induce DED secondary to multiple mechanisms. Moreover, the use of contact lens induces or is associated with DED. However, one of the most emblematic situations is DED caused by surgical procedures such as corneal refractive surgery as in laser-assisted in situ keratomileusis (LASIK) and keratoplasty due to mechanisms intrinsic to the procedure (i.e. corneal nerve cutting) or even by the use of postoperative topical drugs. Cataract surgery, lid surgeries, botulinum toxin application and cosmetic procedures are also considered risk factors to iatrogenic DED, which can cause patient dissatisfaction, visual disturbance and poor surgical outcomes. This report also presents future directions to address iatrogenic DED, including the need for more in-depth epidemiological studies about the risk factors, development of less toxic medications and preservatives, as well as new techniques for less invasive eye surgeries. Novel research into detection of early dry eye prior to surgeries, efforts to establish appropriate therapeutics and a greater attempt to regulate and oversee medications, preservatives and procedures should be considered.

Preservative-free fixed combination of tafluprost 0.0015% and timolol 0.5% in patients with open-angle glaucoma and ocular hypertension: results of an open-label observational study

Background

Efficacy, tolerability and safety of the novel preservative-free fixed combination of tafluprost 0.0015%/timolol 0.5% (Taptiqom^®) were investigated in an observational study in Germany.

Objective

To assess efficacy, tolerability and safety of the preservative-free fixed combination of tafluprost 0.0015%/timolol 0.5% in a real-life setting.

Methods

Intraocular pressure (IOP) was recorded for each eye at baseline (any previous therapy or untreated) and 4–16 weeks after changing medical treatment to or initiating treatment with the preservative-free fixed combination of tafluprost 0.0015%/timolol 0.5%. Change in IOP was evaluated over the study period for all patients and for specific pretreatment subgroups. Clinical signs such as conjunctival hyperemia and lid-parallel conjunctival folds (LIPCOF) were recorded using standardized comparative photographs. Corneal staining, subjective symptoms and local comfort were measured using a four-step scale. All adverse events were recorded.

Results

Among 1,157 patients enrolled, 1,075 patients were treated with the preservative-free fixed combination as the only medication at the final visit. Medical treatment was initiated in 741 patients because of an insufficient IOP-lowering effect of the prior medication. In 343 patients, medication was changed because of tolerability issues. The preservative-free fixed combination lowered IOP significantly in the subgroup of naïve patients, all subgroups with prior monotherapy and patients with prior fixed combinations: naïve patients: −8.9 mmHg, alpha- 2-agonists: −6.4 mmHg, beta-blockers: −5.7 mmHg, carbonic anhydrase inhibitors: −5.2 mmHg, prostaglandins: −4.7 mmHg, fixed-combination prostaglandins/timolol: −2.4 mmHg. At the final visit, clinical signs and subjective symptoms were improved in patients with prior medical therapy. Local comfort was rated as “very good” or “good” by 89.1% of patients at the final visit. Only few adverse events occurred during the treatment period.

Conclusion

The preservative-free fixed combination of tafluprost 0.0015%/timolol 0.5% was effective, well tolerated and showed a good safety profile.

The Role of the P2X7 Receptor in Ocular Stresses: A Potential Therapeutic Target

The P2X7 receptor is expressed in both anterior and posterior segments of the eyeball. In the ocular surface, the P2X7 receptor is activated in case of external aggressions: preservatives and surfactants induce the activation of P2X7 receptors, leading to either apoptosis, inflammation, or cell proliferation. In the retina, the key endogenous actors of age-related macular degeneration, diabetic retinopathy, and glaucoma act through P2X7 receptors’ activation and/or upregulation of P2X7 receptors’ expression. Different therapeutic strategies aimed at the P2X7 receptor exist. P2X7 receptor antagonists, such as divalent cations and Brilliant Blue G (BBG) could be used to target either the ocular surface or the retina, as long as polyunsaturated fatty acids may exert their effects through the disruption of plasma membrane lipid rafts or saffron that reduces the response evoked by P2X7 receptor stimulation. Treatments against P2X7 receptor activation are proposed by using either eye drops or food supplements.

Vision-related quality of life following glaucoma filtration surgery

BACKGROUND

To evaluate vision-related quality of life (VR-QOL) following glaucoma filtration surgery.

METHODS

A total of 103 glaucoma patients scheduled to undergo glaucoma filtration surgery. Prior to and at three months after glaucoma filtration surgery, trabeculectomy or EX-PRESS, all patients completed the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25). A total of 48 patients underwent combined cataract and filtration surgery. The clinical data collected pre- and postoperatively included best-corrected visual acuity (BCVA) and intraocular pressure (IOP).

RESULTS

The IOP decreased significantly from 19.0 ± 8.1 mmHg to 9.7 ± 3.9 mmHg (P < 0.001). Preoperative VFQ-25 composite score (65.8 ± 15.6) was similar to the postoperative score (67.8 ± 16.6). A significantly improved VFQ-25 composite score (pre: 63.2 ± 17.1, post: 67.7 ± 17.8; P = 0.001) was observed in the patients who underwent combined cataract and filtration surgery. There was a significant association between the BCVA changes in the operated eye and the changes in the VFQ-25 composite score (r = -0.315, P = 0.003).

CONCLUSIONS

Although glaucoma filtration surgery by itself did not decrease the VR-QOL in glaucoma patients, there was significant improvement in the VR-QOL after the patients underwent combined cataract and glaucoma filtration surgery.

Switching to preservative-free latanoprost: impact on tolerability and patient satisfaction

Patient satisfaction with glaucoma treatment has been poorly studied to date. Because glaucoma is a chronic condition in which the therapeutic response is dependent on adherence to treatment, patient acceptability is an important factor in achieving satisfactory outcomes. This multicenter, international (Belgium, the Netherlands, and Spain), epidemiological convenience sample survey among patients commencing treatment with preservative-free latanoprost collected data on patient satisfaction with particular regard to tolerability. A total of 1,541 patients were recruited who were predominantly elderly (74% were over 60 years of age) and female (61%). Most of the patients had previously received preserved topical glaucoma medication (69%), 6.7% had previously received preservative-free medication, whereas 24% had not previously been treated for glaucoma. The great majority of patients (>95%) were satisfied with the preservative-free latanoprost treatment. Among the patients who had previously received preserved medication, 73% of patients found preservative-free latanoprost to be better tolerated and 89% found it at least as easy to use as their prior treatment. Patient satisfaction (determined by a 0-100 mm visual analog scale) was improved by 47% on a switch from preserved treatment to preservative-free latanoprost. Intraocular pressure was similar in patients who had previously received preserved (18.3 mmHg), preservative-free (17.8 mmHg) glaucoma medication or who were naïve to treatment (20.3 mmHg). Preservative-free latanoprost provided effective reduction of intraocular pressure with better tolerability and patient satisfaction than preserved glaucoma medication. This tolerability profile can be expected to improve adherence to treatment in glaucoma patients.

Sodium perbarate and benzalkonium chloride induce DNA damage in Chang conjunctival epithelial cells

Content and objective: To investigate and compare the toxic effects of benzalkonium chloride (BAC) and new type oxidative preservative sodium perborate (NaBO₃) on DNA damage, reactive oxygen species (ROS), and cell survival in immortalized human Chang conjunctival cells.

MATERIALS AND METHODS

Cells were exposed to BAC and NaBO₃ in concentrations of 0.00001-0.001% for 30 min. Cell viability was measured by the MTT test. Alkaline comet assay was used to detect DNA damage. Mitochondrial membrane potential (MMP), cell apoptosis, and ROS production were detected by flow cytometry analysis.

RESULTS

Significant changes in the relative cell survival rate in cells were observed after exposure to 0.0005-0.001% BAC for 30 min (p < 0.001). DNA damage and intracellular ROS were observed in a dose-dependent manner with BAC exposure (p < 0.001). However, 0.001% BAC induced less ROS than 0.0005% BAC. A decrease in MMP was also recorded. NaBO₃ did not induce the decrease in cell survival and MMP in low concentration but could induce DNA damage and ROS generation in a 0.001% concentration (p < 0.001).

DISCUSSION AND CONCLUSIONS

BAC can induce DNA damage in human conjunctival epithelial cells; this effect may be related to oxidative stress. Although NaBO₃ did not induce a significant decrease in cell survival and MMP, DNA damage and ROS generation were still detected in high concentration. New type oxidative preservative has less toxicity than the old type, but it still has the tendency of producing genotoxic changes in an in vitro test system.

Pharmacokinetics, Efficacy, and Safety of the Preservative-free Fixed Combination of Tafluprost 0.0015% and Timolol 0.5% in Healthy Volunteers: A Phase I Comparison vs. the Corresponding Preservative-free Monotherapies

PURPOSE

Plasma concentrations of tafluprost acid and timolol were compared after single (Day 1) and repeated (Day 8) instillations of once-daily tafluprost 0.0015%-timolol 0.5% preservative-free (PF) fixed-dose combination (FDC), once-daily PF tafluprost 0.0015%, and twice-daily PF timolol 0.5%.

PATIENTS AND METHODS

Fifteen healthy volunteers were randomized to this double-masked, single-center, three-period cross-over study. A wash-out interval of at least 4 weeks separated each three 8-day dosing period. Blood samples were drawn on the first and last day of each dosing period, prior to the morning dose, as well as 5, 10, 15, 30, and 45 min, and 1, 1.5, 2, 4, 8, and 12 h post-dosing. Sample plasma concentrations of tafluprost acid and/or timolol were determined and maximum concentration (C max), area under the concentration-over-time curve from time zero to the last time point with a quantifiable measurement (AUC0-last), and time to maximum concentration were calculated. Intraocular pressure (IOP), adverse events, and ocular/systemic safety variables were also evaluated.

RESULTS

Plasma concentrations of tafluprost acid were low, with similar levels measured subsequent to either single or repeated dosing of PF FDC and PF tafluprost. On both sampling days, concentrations peaked at 10 min after the dose, and were cleared from the blood circulation by 30 min; average C max ranged from 17 to 24 pg/mL, and AUC0-last from 3 to 5 pg*h/mL. Plasma concentrations of timolol were comparable after the first dose of PF FDC or PF timolol. Concentrations peaked at 15 min post-dose and diminished in a similar manner after 2 h; average C max was 800 pg/mL and AUC0-last 3900 pg*h/mL. As expected, PF timolol produced a higher Day 8 pre-dose timolol concentration than PF FDC (235 vs. 37 pg/mL; p < 0.001, respectively). The Day 8 post-dose changes in timolol concentrations were relative to this pre-dose difference. All study treatments were well tolerated and safe. PF FDC seemed to provide the best IOP reduction.

CONCLUSIONS

PF FDC demonstrated good IOP-lowering efficacy and displayed similar pharmacokinetic characteristics to the monotherapy agents. Exposure to timolol was reduced via the halved dosing.

Medical Management of Glaucoma in the 21st Century from a Canadian Perspective

Glaucoma is a medical term describing a group of progressive optic neuropathies characterized by degeneration of retinal ganglion cells and retinal nerve fibre layer and resulting in changes in the optic nerve head. Glaucoma is a leading cause of irreversible vision loss worldwide. With the aging population it is expected that the prevalence of glaucoma will continue to increase. Despite recent advances in imaging and visual field testing techniques that allow establishment of earlier diagnosis and treatment initiation, significant numbers of glaucoma patients are undiagnosed and present late in the course of their disease. This can lead to irreversible vision loss, reduced quality of life, and a higher socioeconomic burden. Selection of therapeutic approaches for glaucoma should be based on careful ocular examination, patient medical history, presence of comorbidities, and awareness of concomitant systemic therapies. Therapy should also be individualized to patients' needs and preferences. Recent developments in this therapeutic field require revisiting treatment algorithms and integration of traditional and novel approaches in order to ensure optimal visual outcomes. This article provides an overview of recent developments and practice trends in the medical management of glaucoma in Canada. A discussion of the surgical management is beyond the scope of this paper.