Sodium hyaluronate eye drops of different osmolarity for the treatment of dry eye in Sjögren's syndrome patients

Rebamipide Enhances Pathogen Defense and Mitigates Inflammation in a Particulate Matter-Induced Ocular Surface Inflammation Rat Model

Particulate matter (PM) exposure is known to induce significant ocular surface inflammation, necessitating effective therapeutic interventions. This study compared the efficacy of 2% rebamipide (REB) with 0.1% hyaluronic acid (HA) eye drops in investigating the anti-inflammatory and pathogen-clearance effects in a PM-induced ocular surface inflammation model using Sprague-Dawley (SD) rats. Parameters including clinical signs, histological changes, mucin secretions, inflammatory cytokines, mast cell degranulation, dysregulated cell proliferation, and cellular apoptosis were evaluated. 2% REB alleviated ocular surface inflammation by downregulating the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) inflammatory pathway and upregulating epidermal growth factor receptor (EGFR) signaling, thereby enhancing mucin secretion and promoting pathogen clearance. Histopathological analysis, western blot, and immunohistochemical staining revealed a marked reduction in inflammatory markers including MMP-9, IL-1β, TNF-α, IL-17, and CD-4, decreased mast cell degranulation, increased goblet cell density, and enhanced expression of mucins, including MUC5AC and MUC16, in the 2% REB-treated group compared to the 0.1% HA-treated and PM-exposed groups. Moreover, 2% REB demonstrated decreased apoptosis (TUNEL) and reduced uncontrolled cell proliferation (Ki67), indicating improved cellular integrity. In conclusion, 2% REB is a promising treatment option for PM-induced ocular surface inflammation in a rat model compared with 0.1% HA, offering the benefits of reducing inflammation, clearing pathogens, and protecting overall ocular health.

Effects of Ophthalmic Medications on Conjunctival Goblet Cell Density in New Zealand White Rabbits

Introduction

The conjunctiva contains numerous specialized cells called conjunctival goblet cells (CGCs). The topical application of specific eye drops to the ocular surface has conclusively been linked to cause a reduction in CGCs, a condition which has been associated with dry eye and other ocular surface disorders. The purpose of this study was to assess if the use of benzalkonium chloride (BAK) as a preservative in common ophthalmic medications affects CGCs' density in New Zealand white (NZW) rabbit conjunctivas.

Methods

Data from seven preclinical studies conducted between March 2016 and April 2021 were analyzed, involving 146 male NZW rabbits aged 2 to 3 months. Prior to study participation, rabbits underwent a 7-day quarantine period in individual housing, during which their general health was monitored. Rabbits had ad libitum access to water and food, with intake data recorded. Comprehensive ophthalmological examinations were performed on all eyes prior to and throughout the studies. The density of corneal endothelial cells was specifically assessed using AB/PAS staining and quantified with a high-power (40X) field objective (ocular 18 × 22), expressed as a percentage relative to epithelial cells.

Results

No statistically significant differences were found between the with-BAK group and without-BAK group. The mean density in the 30-day group presented a statistically significant higher density than the >30-day group (p = 0.005). Analysis of the treatment revealed that antibiotic/steroid combination group had a higher average number of CGCs compared to both the antihistaminic group (p = 0.004) and hypotensive agent group (p = 0.047).

Conclusion

Exposure to BAK-preserved medications for 30 days results in a higher density of CGCs compared to prolonged exposure to BAK-preserved medications exceeding 30 days. The pharmacological effects and associated cellular damage induced by BAK vary depending on the specific medication with which it is combined.

Efficacy of Perfluorohexyloctane for the Treatment of Patients with Dry Eye Disease: A Meta-Analysis

INTRODUCTION

The aim of the study was to systematically review the evidence from randomized controlled trials that evaluate the efficacy and safety of perfluorohexyloctane in the treatment of dry eye disease.

METHODS

Literature search was conducted on PubMed and Scopus in April 2024 with the search strategy ("perfluorohexyloctane" or "NOV03" or "semifluorinated alkane") and "dry eye." Extension and paired-eyes study were excluded. The risk of bias was assessed using the Cochrane risk-of-bias tool. Forest plots and a summary of findings were prepared for total corneal fluorescein staining (tCFS), tear film break-up time (TFBUT), eye dryness score (EDS), and Ocular Surface Disease Index (OSDI).

RESULTS

The pooled standardized mean difference (SMD) for tCFS after 8 weeks of treatment was -0.53 (95% CI: -0.68 to -0.38; p < 0.001), indicating a significant improvement in patients treated with perfluorohexyloctane. The between-study heterogeneity was moderately high (I2 = 52.0%). No significant differences in TFBUT were observed (SMD = 0.05; 95% CI: -0.16 to 0.25; p = 0.654). Regarding symptoms, patients treated with NOV03 had significantly lower EDS compared to controls (SMD = -0.49; 95% CI: -0.66 to -0.32; p < 0.001), with moderately high heterogeneity (I2 = 71.1%). Conversely, the pooled SMD of OSDI was -0.13 (95% CI: -0.43 to 0.17; p = 0.412), indicating no significant difference.

CONCLUSION

Perfluorohexyloctane is an effective and safe alternative for the treatment of evaporative dry eye disease due to MGD that can significantly reduce tCFS and eye dryness symptoms. More well-designed non-sponsored randomized clinical trials are required to investigate the impact on other ocular surface parameters.

Perfluorohexyloctane ophthalmic solution for dry eye disease: pooled analysis of two phase 3 clinical trials

Background

Dry eye disease (DED) is commonly caused by excessive tear film evaporation due to Meibomian gland dysfunction (MGD). There is a need for DED treatment options that address tear evaporation and benefit patients across a broad range of demographic and disease characteristics. This study evaluated treatment effects of perfluorohexyloctane ophthalmic drop (formerly NOV03) in the pooled dataset from 2 pivotal clinical trials in patients with DED associated with MGD, both in the overall population and in patient subgroups based on sex, age, and baseline severity of eye dryness.

Methods

Pooled data from 2 similarly designed, phase 3, randomized controlled trials (GOBI, MOJAVE) were analyzed. Patients aged ≥18 years with DED administered perfluorohexyloctane (n=614) or hypotonic (0.6% solution) saline control (n=603) four times daily for 8 weeks. Primary endpoints were total corneal fluorescein staining (tCFS) score (National Eye Institute scale, 0-15) and eye dryness visual analog scale (VAS) score (0-100). Efficacy was evaluated using analysis of covariance among patient subgroups (male and female, older [≥65 years] and younger [18 to <65 years], tCFS score <7 and ≥7, VAS eye dryness score <70 and ≥70, MGD score <7 and ≥7, Schirmer I test <10 mm and ≥10 mm).

Results

Reductions in tCFS and VAS eye dryness scores were greater for perfluorohexyloctane versus control. In the overall patient population, least-squares mean treatment difference was -1.1 (95% CI: -1.41 to -0.79; p<0.0001) for tCFS and -9.0 (95% CI: -11.90 to -6.00; p<0.0001) for VAS eye dryness. Treatment favored perfluorohexyloctane over control in all patient subgroup analyses of tCFS and VAS eye dryness. Overall, the most common adverse event with perfluorohexyloctane was blurred vision (2.1% of patients), which was mild and transient.

Conclusions

Compared with a hypotonic saline control, perfluorohexyloctane improved both the signs and symptoms of DED, including in patients with greater self-reported severity of eye dryness.

Clinical trial registration

This study represents an integrated analysis of 2 previous clinical trials: GOBI (ClinicalTrials.gov, NCT04139798) and MOJAVE (ClinicalTrials.gov, NCT04567329).

Exploring Lacrimal Gland Tear Production in Sheep under General Anesthesia: Examining the Potential Impact of Utilizing 1% Hyaluronic Acid Ophthalmic Gel

The aim of the study is to assess the lacrimal gland tear production, using the Schirmer Tear Test (STT), in healthy sheep under general anesthesia and to explore the effects of applying 1% hyaluronic acid ophthalmic gel during general anesthesia. While STT values during anesthesia have been well documented in small animals such as cats and dogs, there seems to be a lack of information available for ruminants like sheep. This gap in the literature highlights the need for further research and exploration into tear production in sheep under anesthesia. The experimental research conducted on twelve adults female sheep provided valuable insights into tear production under anesthesia. By assessing tear production at various key time points the study was able to capture the changes in tear production throughout anesthesia and revealed a significant decrease in Schirmer Tear Test values in all sheep, following general anesthesia. The results showed that closing and taping the eye yielded determined better outcomes compared to administering a 1% lubricant ophthalmic gel. This finding suggests that eye care during anesthesia can impact tear production in sheep.

Managing the ocular surface after glaucoma filtration surgery: an orphan topic

BACKGROUND

Ocular surface (OS) disorders before glaucoma filtration surgery (GFS) have been considered to play a crucial role influencing the surgical outcome. Conversely, the impact of surgery itself on the OS is almost completely overlooked, though evidence suggest that ocular surface disease (OSD) may be induced in patients by GFS. This review analyzes the determinants involved in the OSD development after GFS, the clinical features and related consequences, the main diagnostic hallmarks, as well as the therapeutic strategies for its management.

METHODS

The PubMed database was utilized for the literature examination. Keywords that were searched included ocular surface disease, glaucoma filtration surgery, filtration bleb, post-surgical management, and quality of life.

RESULTS

After GFS, OSD is promoted by peri- and post-operative factors, such as the filtration bleb (FB) development, combined surgical approach with phacoemulsification, the use of antifibrotic agents and the reintroduction of antiglaucoma medications. This particular form of OSD that present similar clinical features to mild to moderate dry eye, can be named as post-glaucoma surgery-OSD (PGS-OSD). PGS-OSD may negatively affect the FB functionality, thus potentially hindering the disease control, and significantly worsen the patient quality of life (QOL).

CONCLUSIONS

Clinicians are encouraged to routinely include the OS evaluation after GFS and to consider proper management when the occurrence of PGS-OSD worsen the patient's QOL or exert negative effects to the FB functionality. An outline summarizing the main risk factors and the most appropriate therapeutic options to mitigate the PGS-OSD was proposed to support the routine practice.

A comparison between hyaluronic acid and other single ingredient eye drops for dry eye, a review

Dry eye disease (DED) is a highly prevalent and debilitating condition. Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan that has a long history as a safe and effective DED treatment. HA is frequently used as a comparator when assessing other topical DED treatments. This study aims to summarise and critically evaluate the literature describing all isolated active ingredients that have been directly compared with HA in the treatment of DED. A literature search was conducted in Embase using Ovid on the 24th of August 2021 and in PubMed including MEDLINE on the 20th of September 2021. Twenty-three studies met the inclusion criteria, 21 of which were randomised controlled trials. Seventeen different ingredients representing six treatment categories were compared with HA treatment. Most measures showed no significant difference between treatments, suggesting either equivalency of treatments or that studies were underpowered. Only two ingredients were represented in more than two studies; carboxymethyl cellulose treatment appears equivalent to HA treatment, while Diquafosol treatment appears superior to HA treatment. Drop-frequency varied from one to eight drops daily. No single study explained the choice of drop frequency. Nine studies used a HA concentration of 0.1% which may be below therapeutic levels. Nine studies reported using preserved formulations, six of them with differences in preservatives between the compared groups. Thirteen studies were financially linked to industry. No major complications were reported. Studies were not designed to find differences in treatment effects for different types or severities of DED. HA is a good comparator treatment when assessing other DED treatments, although consensus after decades of use is still lacking for best choice of concentration, molecular weight and drop tonicity. Well-designed studies are needed to determine an evidence-based standard for HA treatment to be used as comparator.

Protecting Tear-Film Stability under Adverse Environmental Conditions Using a Mucomimetic with a Non-Newtonian Viscosity Agent

Background and Objectives: Tamarind-seed polysaccharide (TSP) and hyaluronic acid (HA) have mucoadhesive properties that improve drug absorption and delay in drug elimination from the ocular surface. We aimed to evaluate TSP/HA-containing formulation for its efficiency in dry-eye symptoms induced by adverse environments and the interaction between mucomimic polymer and tear-film parameters. Materials and Methods: The participants were exposed to 5% relative humidity (RH) in a Controlled Environment Chamber (CEC) under constant room temperature (21 °C). Tear-film parameters were assessed at 40% RH and 5% RH. Rohto Dry Eye Relief drops were used in the two treatment modalities, protection (drops instilled before exposure to the dry environment) and relief (drops instilled after exposure to the dry environment). The HIRCAL grid, Servomed EP3 Evaporimeter, and Keeler's TearScope-Plus were used to screen for non-invasive tear break-up time (NITBUT), tear evaporation rate, and lipid-layer thickness (LLT) using protection and relief treatment methodology. Results: LLT was found to be significantly thinner at 5% RH compared with at 40% RH (p = 0.007). The median LLT dropped from 50-70 nm (grade 3) at 40% RH to 10-50 nm (grade 2) at 5% RH. TSP/HA eye drops significantly augment LLT in both treatment modalities, protection (p = 0.01) and relief (p = 0.004) at 5% RH. The mean evaporation rate doubled from 40.93 at 40% RH to 82.42 g/m2/h after exposure to 5% RH. In protection mode, the TSP/HA allowed the average evaporation rate to be much lower than when no TSP/HA was used at 5% RH (p < 0.008). No alteration in evaporation rate was recorded when the TSP/HA drop was used after exposure (relief). The mean NITBUT was reduced from 13 s in normal conditions to 6 s in the dry environment. Instillation of TSP/HA eye drops resulted in significant improvement (p = 0.006) in tear stability, where the NITBUT increased to 8 s in both protection (before exposure) and relief (after exposure) (p = 0.001). Although improved, these values were still significantly lower than NITBUT observed at 40% RH. Conclusions: Significant protection of tear-film parameters was recorded post instillation of TSP/HA eye drop under a desiccating environment. Both treatment methods (protection and relief) were shown to be effective. The presence of TSP/HA enhances the effectiveness of teardrops in protecting the tear-film parameters when exposed to adverse environments.

NOV03 for Signs and Symptoms of Dry Eye Disease Associated With Meibomian Gland Dysfunction: The Randomized Phase 3 MOJAVE Study

PURPOSE

To evaluate the efficacy and safety of NOV03 (perfluorohexyloctane) ophthalmic drop for the treatment of signs and symptoms of dry eye disease (DED) associated with meibomian gland dysfunction (MGD).

DESIGN

Randomized, double-masked, controlled trial.

METHODS

Patients ≥18 years of age with a history of DED and signs of MGD were randomly assigned 1:1 to treatment with NOV03 or hypotonic saline (0.6%) 4 times daily for 8 weeks. The primary sign and symptom endpoints were change from baseline to week 8 in total corneal fluorescein staining (tCFS; National Eye Institute scale) and eye dryness score (0-100 visual analog scale), respectively.

RESULTS

A total of 620 patients (NOV03, n = 311; saline, n = 309) were randomized and treated. Least-squares (LS) mean change from baseline to week 8 was statistically significantly greater for NOV03 compared with saline for both tCFS (-2.3 vs -1.1; LS mean treatment difference, -1.2 [95% confidence interval -1.7 to -0.8]; P < .001) and visual analog scale dryness score (-29.4 vs -19.2; LS mean treatment difference, -10.2 [95% CI -14.4 to -6.1]; P < .001), with statistically significant between-group differences observed as early as week 2. The incidence of ocular adverse events was similar for NOV03 (12.9%) and saline (12.3%). There were no serious adverse events and no adverse events leading to treatment discontinuation.

CONCLUSIONS

In this randomized controlled trial of patients with DED associated with MGD, NOV03 significantly reduced both signs and symptoms of DED compared with hypotonic saline control. NOV03 was well tolerated, with an adverse event profile similar to that of saline.

Evaluation of different treatment modalities on the efficacy of hydroxypropyl Guar (HP-Guar) formulation on tear film stability (TFS) in subjects exposed to adverse environmental conditions

The study aimed to assess the efficacy of hydroxypropyl guar (HP) formulation (Systane) to protect tear film parameters under desiccating environment using protection and relief treatment modalities. The subjects were exposed to adverse environmental conditions using a Controlled Environment Chamber (CEC) where the relative humidity (RH) was 5% and the ambient temperature was 21 °C and screened for Tear break-up time (TBUT), Tear film evaporation rate (TFER) and lipid layer thickness (LLT) using the HIRCAL grid, Servomed EP3 Evaporimeter and Keeler's TearScope-Plus respectively. Significant improvement in LLT was noticed in the protection modality. The mean tear film evaporation rate doubled after exposure to the humidity of 5% to a value of 105.37 g/m²/h (0.29 µl/min). All subjects displayed a significant reduction in non-invasive tear break-up time (NITBUT) with a mean NITBUT of 7.7 s after exposure to a desiccating environment for 15 min. A significant increase in NITBUT after the instillation of the drops was recorded in both methods. The results obtained from this study showed that a solution containing HP-Guar significantly improves tear film parameters under a desiccating environment. Apart from the tear evaporation rate, all tear parameters showed improvement after the use of HP-Guar eye drops. It is evident that tear film parameters respond differently to the management modalities and using CEC has the potential to provide researchers with a readily available method to evaluate the efficiency of tear supplementation.

Perfluorohexyloctane Eye Drops for Dry Eye Disease Associated With Meibomian Gland Dysfunction in Chinese Patients: A Randomized Clinical Trial

Importance

Meibomian gland dysfunction (MGD) is a leading cause of evaporative dry eye disease (DED). Medical and surgical management for DED is limited; therefore, new treatment options are sought.

Objective

To evaluate the efficacy and safety of SHR8058 (perfluorohexyloctane) eye drops in Chinese patients with DED associated with MGD through 57 days.

Design, Setting, and Participants

This was a randomized, multicenter, double-masked, saline-controlled, phase 3 clinical trial conducted from February 4, 2021, to September 7, 2022. Patients were recruited from the departments of ophthalmology in 15 hospitals in China. Patients with DED associated with MGD were enrolled between February 4 and July 1, 2021. The diagnosis was based on patient complaint of DED symptoms, an ocular surface disease index of 25 or higher, tear film break-up time of 5 seconds or less, Schirmer I test without anesthesia results of 5 mm or more at 5 minutes, total corneal fluorescein staining (tCFS) score of 4 to 11, and an MGD score of 3 or higher.

Interventions

Eligible participants were randomly assigned 1:1 to receive perfluorohexyloctane eye drops or 0.6% sodium chloride [NaCl]) 4 times per day.

Main Outcomes and Measures

The primary end points were the changes from baseline in tCFS and eye dryness scores at day 57.

Results

A total of 312 participants were included in the analysis: 156 (mean [SD] age, 45.4 [15.2] years; 118 female [75.6%]) in the perfluorohexyloctane group and 156 (mean [SD] age, 43.7 [15.1] years; 127 female [81.4%]) in the NaCl group. Both primary end points were achieved, ie, changes from baseline at day 57 of tCFS score (mean [SD], -3.8 [2.7] vs -2.7 [2.8]) and eye dryness score (mean [SD], -38.6 [21.9] vs -28.3 [20.8]) in the perfluorohexyloctane group were superior to the control group, with estimated mean differences of -1.14 (95% CI, -1.70 to -0.57; P < .001) and -12.74 (95% CI, -17.20 to -8.28, P < .001), respectively. Improvements on both end points appeared to be noted on day 29 and day 15, respectively, and maintained through day 57. Compared with the control, perfluorohexyloctane eye drops also alleviated symptoms including pain (mean [SD] tCFS score, 26.7 [23.7] vs -18.7 [22.5]; P = .003), awareness of DED symptoms (mean [SD] tCFS score, -38.1 [25.1] vs -23.7 [27.6]; P < .001), and frequency of dryness (mean [SD] tCFS score, -43.3 [23.8] vs -29.1 [24.8]; P < .001). Treatment-emergent adverse events occurred in 34 participants (21.8%) and 40 participants (25.6%) in the perfluorohexyloctane and control groups, respectively.

Conclusions and Relevance

Results of this randomized clinical trial demonstrate that perfluorohexyloctane eye drops significantly ameliorated the signs and symptoms of DED associated with MGD with a rapid efficacy as well as satisfactory tolerability and safety through 57 days. Findings support the use of these eye drops if results can be confirmed independently and over longer time periods.

Trial Registration

ClinicalTrials.gov Identifier: NCT05515471.

Hyaluronic acid in the treatment of dry eye disease

Dry eye disease (DED) is a highly prevalent and debilitating condition affecting several hundred million people worldwide. Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan commonly used in the treatment of DED. This review aims to critically evaluate the literature on the safety and efficacy of artificial tears containing HA used in DED treatment. Literature searches were conducted in PubMed, including MEDLINE, and in Embase via Ovid with the search term: "(hyaluronic acid OR hyaluronan OR hyaluronate) AND (dry eye OR sicca)". A total of 53 clinical trials are included in this review, including eight placebo-controlled trials. Hyaluronic acid concentrations ranged from 0.1% to 0.4%. Studies lasted up to 3 months. A broad spectrum of DED types and severities was represented in the reviewed literature. No major complications or adverse events were reported. Artificial tears containing 0.1% to 0.4% HA were effective at improving both signs and symptoms of DED. Two major gaps in the literature have been identified: 1. no study investigated the ideal drop frequency for HA-containing eyedrops, and 2. insufficient evidence was presented to recommend any specific HA formulation over another. Future investigations assessing the optimal drop frequency for different concentrations and molecular weights of HA, different drop formulations, including tonicity, and accounting for DED severity and aetiology are essential for an evidence-based, individualized approach to DED treatment.

Hyaluronic acid in the treatment of dry eye disease

Dry eye disease (DED) is a highly prevalent and debilitating condition affecting several hundred million people worldwide. Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan commonly used in the treatment of DED. This review aims to critically evaluate the literature on the safety and efficacy of artificial tears containing HA used in DED treatment. Literature searches were conducted in PubMed, including MEDLINE, and in Embase via Ovid with the search term: "(hyaluronic acid OR hyaluronan OR hyaluronate) AND (dry eye OR sicca)". A total of 53 clinical trials are included in this review, including eight placebo-controlled trials. Hyaluronic acid concentrations ranged from 0.1% to 0.4%. Studies lasted up to 3 months. A broad spectrum of DED types and severities was represented in the reviewed literature. No major complications or adverse events were reported. Artificial tears containing 0.1% to 0.4% HA were effective at improving both signs and symptoms of DED. Two major gaps in the literature have been identified: 1. no study investigated the ideal drop frequency for HA-containing eyedrops, and 2. insufficient evidence was presented to recommend any specific HA formulation over another. Future investigations assessing the optimal drop frequency for different concentrations and molecular weights of HA, different drop formulations, including tonicity, and accounting for DED severity and aetiology are essential for an evidence-based, individualized approach to DED treatment.

Optimization of Lipid Nanoparticles by Response Surface Methodology to Improve the Ocular Delivery of Diosmin: Characterization and In-Vitro Anti-Inflammatory Assessment

Diosmin is a flavonoid with a great variety of biological activities including antioxidant and anti-inflammatory ones. Its cytoprotective effect in retinal pigment epithelium cells under high glucose conditions makes it a potential support in the treatment of diabetic retinopathy. Despite its benefits, poor solubility in water reduces its potential for therapeutic use, making it the biggest biopharmaceutical challenge. The design of diosmin-loaded nanocarriers for topical ophthalmic application represents a novelty that has not been yet explored. For this purpose, the response surface methodology (RSM) was used to optimize nanostructured lipid carriers (NLCs), compatible for ocular administration, to encapsulate diosmin and improve its physicochemical issues. NLCs were prepared by a simple and scalable technique: a melt emulsification method followed by ultrasonication. The experimental design was composed of four independent variables (solid lipid concentration, liquid lipid concentration, surfactant concentration and type of solid lipid). The effect of the factors was assessed on NLC size and PDI (responses) by analysis of variance (ANOVA). The optimized formulation was selected according to the desirability function (0.993). Diosmin at two different concentrations (80 and 160 µM) was encapsulated into NLCs. Drug-loaded nanocarriers (D-NLCs) were subjected to a physicochemical and technological investigation revealing a mean particle size of 83.58 ± 0.77 nm and 82.21 ± 1.12 nm, respectively for the D-NLC formulation prepared with diosmin at the concentration of 80 µM or 160 µM, and a net negative surface charge (−18.5 ± 0.60 and −18.0 ± 1.18, respectively for the two batches). The formulations were analyzed in terms of pH (6.5), viscosity, and adjusted for osmolarity, making them more compatible with the ocular environment. Subsequently, stability studies were carried out to assess D-NLC behavior under different storage conditions up to 60 days, indicating a good stability of NLC samples at room temperature. In-vitro studies on ARPE-19 cells confirmed the cytocompatibility of NLCs with retinal epithelium. The effect of D-NLCs was also evaluated in-vitro on a model of retinal inflammation, demonstrating the cytoprotective effect of D-NLCs at various concentrations. RSM was found to be a reliable model to optimize NLCs for diosmin encapsulation.

Hyaluronic Acid and Galacto-Xyloglucan Eyedrop Efficacy in Young-Adult Oral Contraceptive Users of Childbearing Age

To assess the efficacy of 0.4% hyaluronic acid and 0.2% galacto-xyloglucan for the subjective symptoms of dry eye disease and tear film invasive and noninvasive signs in 34 young-adult oral contraceptive users of childbearing age, a prospective, longitudinal, single-blind, clinical study was performed in a population of childbearing-age oral-contraceptive consumers. Subjective dry eye disease questionnaires, and invasive and noninvasive tear film assessments were reported before and after six weeks of hyaluronic acid with galacto-xyloglucan (HA-GX) treatment versus hyaluronic acid alone (HA). HA-GX treatment resulted in a greater decrease in the ocular surface disease index (17.01 ± 11.36 score points, p < 0.01) than the HA variation (11.61 ± 11.18 score points, p < 0.01). The standard patient evaluation of eye dryness also decreased more in the HA-GX group (4.06 ± 5.50 score points, p < 0.01) than in the HA alone group (0.70 ± 3.16, p = 0.21). Regarding noninvasive break-up time (NIBUT), the HA-GX group’s first NIBUT achieved an increase of 1.75 ± 1.16 s, p < 0.01, while the HA-alone group increased by only 0.54 ± 1.01 s, p < 0.01. The HA-GX group’s mean NIBUT reported an increase of 3.72 ± 5.69 s, p < 0.01; however, the HA-alone group achieved 2.19 ± 5.26 s, p = 0.05. Hyaluronic acid in combination with galacto-xyloglucan significantly decreased subjective dry eye disease symptoms and increased first and mean NIBUT compared to hyaluronic acid alone. Galacto-xyloglucan added efficacy in young-adult childbearing-age oral contraceptive users.

Lipid, Aqueous and Mucin Tear Film Layer Stability and Permanence within 0.15% Liposome Crosslinked Hyaluronic Acid versus 0.15% Non-Crosslinked Hyaluronic Acid Measured with a Novel Non-Invasive Ocular Surface Analyzer

To evaluate the stability and permanence of the liquid film created after the instillation of 0.15% crosslinked hyaluronic acid with liposomes and crocin versus the effect of 0.15% standard hyaluronic acid, a prospective, longitudinal, single-blind, single-center study was conducted in symptomatic populations with a novel noninvasive ocular surface analyzer. Limbal and bulbar redness classification, lipid layer thickness, tear meniscus height, and first and mean noninvasive break-up time (FNIBUT and MNIBUT) were performed before and 30 and 45 min after liposome-crosslinked hyaluronic acid (LCHA) and standard hyaluronic acid (HA) eye drop instillations. LCHA had a higher lipid layer thickness than HA (grades 2.00 ± 0.83 and 1.17 ± 0.63 on the Guillon pattern, respectively). LCHA achieved a better tear meniscus height than HA (0.23 ± 0.02 and 0.21 ± 0.02 mm, respectively). LCHA improved FNIBUT and MNIBUT more than HA (for FNIBUT, 6.30 ± 0.94 and 4.77 ± 0.89 s, respectively. For MNIBUT, 17.23 ± 5.11 and 12.41 ± 4.18 s, respectively). Crosslinking hyaluronic acid with liposomes and crocin significantly increases the permanence and stability of the lipid, aqueous, and mucin tear film layers. In a short-term period, liposome and crosslinked hyaluronic acid achieved better first and mean noninvasive break-up times than standard hyaluronic acid.

Altered Ocular Surface Health Status and Tear Film Immune Profile Due to Prolonged Daily Mask Wear in Health Care Workers

Prolonged daily face mask wearing over several months might affect health of the ocular surface and is reported to be associated with complaints of discomfort and dry-eye-like symptoms. We studied the ocular surface clinical parameters, tear soluble factors and immune cell proportions in ophthalmologists practicing within similar environmental conditions (n = 17) at two time points: pre-face-mask period (Pre-FM; end of 2019) and post-face-mask-wearing period (Post-FM; during 2020 COVID-19 pandemic), with continuous (~8 h/day) mask wear. A significant increase in ocular surface disease index (OSDI) scores without changes in tear breakup time (TBUT), Schirmer’s test 1 (ST1) and objective scatter index (OSI) was observed Post-FM. Tear soluble factors (increased—IL-1β, IL-33, IFNβ, NGF, BDNF, LIF and TSLP; decreased—IL-12, IL-13, HGF and VEGF-A) and mucins (MUC5AC) were significantly altered Post-FM. Ex vivo, human donor and corneoscleral explant cultures under elevated CO₂ stress revealed that the molecular profile, particularly mucin expression, was similar to the Post-FM tear molecular profile, suggesting hypercapnia is a potential contributor to ocular surface discomfort. Among the immune cell subsets determined from ocular surface wash samples, significantly higher proportions of leukocytes and natural killer T cells were observed in Post-FM compared to Pre-FM. Therefore, it is important to note that the clinical parameters, tear film quality, tear molecular factors and immune cells profile observed in prolonged mask-wear-associated ocular surface discomfort were distinct from dry eye disease or other common ocular surface conditions. These observations are important for differential diagnosis as well as selection of appropriate ocular surface treatment in such subjects.

Influence of Selected Ophthalmic Fluids on the Wettability and Hydration of Hydrogel and Silicone Hydrogel Contact Lenses—In Vitro Study

This study attempts to evaluate the effect of incubation in selected ophthalmic fluids on contact lenses (Etafilcon A, Omafilcon A, Narafilcon A, Senofilcon A). Four research groups differing in the incubation environment were created: (1) initial state, (2) contact lens solution (CLS), (3) contact lens solution and eye drops (ED) and (4) eye drops. Dehydration by gravimetric method and the contact angle (CA) by the sessile drop method were tested. The surface free energy (SFE) was also calculated with the use of several methods: Owens–Wendt, Wu, Neumann, and Neumann–Kwok. The greatest changes in the dehydration profile were observed for contact lenses incubated in ED. The most noticeable changes in CA values were observed for contact lenses incubated in ED, in which it was not possible to settle water drop after incubation. On the basis of SFE analysis, higher values were found for hydrogel contact lenses, e.g., according to the Owens–Wendt method, they ranged from 54.45 ± 6.56 mJ/m2 to 58.09 ± 4.86 mJ/m2, while in the case of silicone-hydrogel contact lenses, they ranged from 32.86 ± 3.47 mJ/m2 to 35.33 ± 6.56 mJ/m2. Incubation in all tested environments decreased the SFE values, but the differences were in most cases statistically insignificant. Calculating the SFE may be a useful method as it can be used to estimate the possibility of bacteria adhering to contact lens surfaces.

Assessment of the Efficiency of HP-Guar and hyaluronic Acid Tear Supplements to Control Tear Film Evaporation Rate in Dry Eye Subjects

Background:

The most common factor that could lead to dryness is the accelerated tear evaporation rate. Controlling the tear evaporation rate is increasingly used as a method to control dry eye complications. The present study explores the effects of different tear supplements formulations on tear film evaporation rate.

Objective:

This study aimed to evaluate the short-term effects of Systane ULTRA and Artelac Advanced eye drops on the tear film evaporation rate.

Methods:

Fifteen male dry eye subjects were enrolled in the current study. Tear film parameters were observed at several time points post installation (10, 20, 30, and 60 min). The tear film parameters observed in the current study were tear evaporation rate, noninvasive breakup time (NITBUT) and tear meniscus height (TMH). Two visits were required to conduct this study. One visit was conducted to assess the physiological tear film parameters with the use of Systane® ULTRA eye drop. The other visit was conducted to assess tear film parameters with the use of Artelac Advanced eye drop.

Results:

The mean tear evaporation rate at baseline was 52.58 ± 23.24 g/m2 h. A box plot of tear evaporation showed a reduction in tear film evaporation rate after instillation of Systane eye drop. A drop in tear film evaporation rate of 14% was observed at 20 and 60 min time point after instillation of Systane ULTRA eye drop. A significant increase in NITBUT was found after instillation of Systane ULTRA (P = 0.01) and Artelac Advanced (P = 0.02).

Conclusion:

The current study indicates a significant improvement in the tear film parameters using both HP-Guar and hyaluronic acid formulations. However, it was apparent that the use of HP-Guar was superior to hyaluronic acid in controlling the tear evaporation rate in dry eye subjects.

A randomized multicenter clinical evaluation of sequential application of 0.3% and 0.15% hyaluronic acid for treatment of dry eye

PURPOSE

We report the clinical efficacy of sequential applications of 0.3% and 0.15% unpreserved hyaluronic acid (HA) for the treatment of dry eye disease (DED).

STUDY DESIGN

Randomized clinical trial.

METHODS

Patients over 19 years of age with DED level 2 or higher, corneal fluorescein staining (CFS) score > 1, and tear break-up time (TBUT) < 10 s were included. Seventy-six patients were randomly assigned to the 0.15% HA group, 0.3% HA group, or combination group. Each group applied two drops of 0.15% or 0.3% HA, or a single drop of both 0.3% and 0.15% HA. Patients were evaluated using the ocular surface disease index (OSDI), CFS and conjunctival fluorescein stain score, TBUT, and blurring/discomfort after application at baseline, 4 weeks, and 8 weeks.

RESULTS

The combination group had the greatest improvement in CFS score from baseline to 8 weeks, compared with the 0.15% and 0.3% HA group (p < 0.001). The combined CFS-OSDI responder rates of the combination group (CFS score = 0 and OSDI ≥ 50% improvement at 8 weeks) were significantly higher than those of the 0.15% and 0.3% groups (p = 0.037). At 4 and 8 weeks, blurring after application in both the 0.3% and combination groups was significantly higher than in the 0.15% group, despite no difference between the 0.3% and combination groups. There were no differences in CFS and conjunctival staining score, TBUT, or OSDI within the three groups at baseline, 4 weeks, and 8 weeks.

CONCLUSIONS

Sequential application of 0.3% and 0.15% HA improved symptoms/signs in moderate to severe DED patients.

Dry eye: why artificial tears are not always the answer

Dry eye disease (DED) is a multifactorial disease that manifests in patients with a variety of symptoms and signs such as ocular pain, visual issues, rapid tear evaporation and/or decreased tear production. It is a global health problem and is the leading cause of optometry and ophthalmology clinic visits. The mainstay therapy for DED is artificial tears (ATs), which mimics tears and improves tear stability and properties. ATs have been found to improve symptoms and signs of disease in all DED subtypes, including aqueous deficient DED and evaporative DED. However, given the heterogeneity of DED, it is not surprising that ATs are not effective in all patients. When AT fails to relieve symptoms and/or signs of DED, it is critical to identify the underlying contributors to disease and escalate therapy appropriately. This includes underlying systemic diseases, meibomian gland dysfunction, anatomical abnormalities and neuropathic dysfunction. Thus, this review will discuss the benefits and limitations of ATs and review conditions when escalation of therapy should be considered in DED.

Modern approach to the treatment of dry eye, a complex multifactorial disease: a P.I.C.A.S.S.O. board review

Dry eye disease (DED) is a growing public health concern affecting quality of life and visual function, with a significant socio-economic impact. It is characterised by the loss of homoeostasis, resulting in tear film instability, hyperosmolarity and inflammation of the ocular surface. If the innate immune response is unable to cope with internal bodily or environmental adverse conditions, the persistent, self-maintaining vicious circle of inflammation leads to the chronic form of the disease. Treatment of DED should be aimed at the restoration of the homoeostasis of the ocular surface system. A proper diagnostic approach is fundamental to define the relevance and importance of each of the DED main pathogenic factors, namely tear film instability, epithelial damage and inflammation. Consideration also needs to be given concerning two other pathogenic elements: lid margin changes and nerve damage. All the factors that maintain the vicious circle of DED in the patient's clinical presentation have to be considered and possibly treated simultaneously. The treatment should be long-lasting and personalised since it has to be adapted to the different clinical conditions observed along the course of the disease. Since DED treatment is frequently unable to provide fast and complete relief from symptoms, empathy with patients and willingness to explain to them the natural history of the disease are mandatory to improve patients' compliance. Furthermore, patients should be instructed about the possible need to increase the frequency and/or change the type of treatment according to the fluctuation of symptoms, following a preplanned rescue regimen.

Ophthalmologic Manifestations of Primary Sjögren's Syndrome

Sjögren’s syndrome (SS) is a chronic, progressive, inflammatory, autoimmune disease, characterized by the lymphocyte infiltration of exocrine glands, especially the lacrimal and salivary, with their consequent destruction. The onset of primary SS (pSS) may remain misunderstood for several years. It usually presents with different types of severity, e.g., dry eye and dry mouth symptoms, due to early involvement of the lacrimal and salivary glands, which may be associated with parotid enlargement and dry eye; keratoconjunctivitis sicca (KCS) is its most common ocular manifestation. It is still doubtful if the extent ocular surface manifestations are secondary to lacrimal or meibomian gland involvement or to the targeting of corneal and conjunctival autoantigens. SS is the most representative cause of aqueous deficient dry eye, and the primary role of the inflammatory process was evidenced. Recent scientific progress in understanding the numerous factors involved in the pathogenesis of pSS was registered, but the exact mechanisms involved still need to be clarified. The unquestionable role of both the innate and adaptive immune system, participating actively in the induction and evolution of the disease, was recognized. The ocular surface inflammation is a central mechanism in pSS leading to the decrease of lacrimal secretion and keratoconjunctival alterations. However, there are controversies about whether the ocular surface involvement is a direct autoimmune target or secondary to the inflammatory process in the lacrimal gland. In this review, we aimed to present actual knowledge relative to the pathogenesis of the pSS, considering the role of innate immunity, adaptive immunity, and genetics.

Formulation Considerations for the Management of Dry Eye Disease

Dry eye disease (DED) is one of the most common ocular surface disorders characterised by a deficiency in quality and/or quantity of the tear fluid. Due to its multifactorial nature involving several inter-related underlying pathologies, it can rapidly accelerate to become a chronic refractory condition. Therefore, several therapeutic interventions are often simultaneously recommended to manage DED efficiently. Typically, artificial tear supplements are the first line of treatment, followed by topical application of medicated eyedrops. However, the bioavailability of topical eyedrops is generally low as the well-developed protective mechanisms of the eye ensure their rapid clearance from the precorneal space, thus limiting ocular penetration of the incorporated drug. Moreover, excipients commonly used in eyedrops can potentially exhibit ocular toxicity and further exacerbate the signs and symptoms of DED. Therefore, formulation development of topical eyedrops is rather challenging. This review highlights the challenges typically faced in eyedrop development, in particular, those intended for the management of DED. Firstly, various artificial tear supplements currently on the market, their mechanisms of action, as well as their application, are discussed. Furthermore, formulation strategies generally used to enhance ocular drug delivery, their advantages and limitations, as well as their application in commercially available DED eyedrops are described.

Lipo-PEG nano-ocular formulation successfully encapsulates hydrophilic fluconazole and traverses corneal and non-corneal path to reach posterior eye segment

The present study describes a special lipid-polyethylene glycol matrix solid lipid nanoparticles (SLNs; 138 nm; -2.07 mV) for ocular delivery. Success of this matrix to encapsulate (entrapment efficiency - 62.09%) a hydrophilic drug, fluconazole (FCZ-SLNs), with no burst release (67% release in 24 h) usually observed with most water-soluble drugs, is described presently. The system showed 164.64% higher flux than the marketed drops (Zocon^®) through porcine cornea. Encapsulation within SLNs and slow release did not compromise efficacy of FCZ-SLNs. Latter showed in vitro and in vivo antifungal effects, including antibiofilm effects comparable to free FCZ solution. Developed system was safe and stable (even to sterilisation by autoclaving); and showed optimal viscosity, refractive index and osmotic pressure. These SLNs could reach up to retina following application as drops. The mechanism of transport via corneal and non-corneal transcellular pathways is described by fluorescent and TEM images of mice eye cross sections. Particles streamed through the vitreous, crossed inner limiting membrane and reached the outer retinal layers.

Safety and Tolerability of an Eye Drop Based on 0.6% Povidone-Iodine Nanoemulsion in Dry Eye Patients

Purpose: To evaluate safety and tolerability on the ocular surface of an anti-septic formulation containing 0.6% povidone–iodine (0.6% PVI) for a 4 week period.

Methods: An observational, prospective study included 20 mild-moderate dry eye disease (DED) patients who enrolled at the Ocular Surface Disease Unit of the University of Messina, receiving 0.6% PVI eye drops for 28 days, 2 drops twice daily (BID). The assessment included the Ocular Surface Disease Index questionnaire; symptoms score (0 = absent to 3 = severe) for burning, ocular dryness, foreign body sensation, watery eyes, tearing, photophobia, and ocular pain; fluorescein tear break-up time (TBUT); and corneal-conjunctival staining, performed at baseline (T0), after 7 (T7) and 28 (T28). Schirmer I-test, corneal endothelial cell count, intraocular pressure, and fundus examination were performed at T0 and T28. The main outcome measures were TBUT and corneal-conjunctival staining as markers of ocular surface homeostasis. For statistical analysis, Student's T-test and Wilcoxon test were used as appropriate.

Results: No significant alterations of the safety parameters were found throughout the study. Further, at T28 a significant improvement of burning, ocular dryness, foreign body sensation, and watery eyes (T0 vs. T28 P < 0.03) were observed; corneal-conjunctival staining improved at T28 (T0 vs. T28 P < 0.0001), and TBUT improved already at T7 (T0 vs. T7 P = 0.0008) lasting so till the end of the study. The only adverse event was mild burning at instillation for the first 3 days of treatment in most of the patients.

Conclusions: The treatment with 0.6% PVI was safe and well tolerated in a group of patients with a damaged ocular surface.

Efficacy and Safety of Sodium Hyaluronate/chondroitin Sulfate Preservative-free Ophthalmic Solution in the Treatment of Dry Eye: A Clinical Trial

Purpose: To evaluate the efficacy of a preservative free sodium hyaluronate/chondroitin sulfate ophthalmic solution (SH/CS-PF) in patients with dry eye disease (DED).Methods: This was a randomized phase IV, multicentric, prospective, double-blind clinical trial. Intent-to-treat (ITT) and per-protocol (PP) analyses were performed. Patients were assigned to receive either SH/CS-PF, Systane® Ultra (PEG/PG) or Systane® Ultra PF (PEG/PG-PF) for 90 days. A total of 326 patients were included in the ITT, and 217 in the PP analysis. Efficacy endpoints were goblet cell density, Nelson's grades (conjunctival impression cytology), tear break-up time (TBUT), Ocular Surface Disease Index (OSDI), and Schirmer's test. Other parameters included were tolerability, measured by the ocular symptomatology; and safety, measured through corneal staining, intraocular pressure, visual acuity and adverse events.Results: In the ITT, there was a significant increase in mean goblet cell density in all treatments compared with their baseline (28.4% vs 21.4% and 30.8%), without difference between arms (p = .159). Eyes exposed to SH/CS-PF, PEG/PG and PEG/PG-PF showed Grade 0-I squamous metaplasia (85.5%, 87.9% and 93.2%, respectively). Similar improvements were observed for TBUT (1.24 ± 2.3s vs 1.27 ± 2.4s and 1.39 ± 2.3s) and OSDI scores at day 90 (-8.81 ± 8.6 vs -7.95 ± 9.2 and -8.78 ± 9.8), although no significant intergroup difference was found. Schirmer's test also presented improvement compared to baseline (1.38 ± 4.9 vs 1.50 ± 4.7 and 2.63 ± 5.9), with a significantly higher variation for PEG/PG-PF. There were no significant differences between treatments for any tolerability and safety parameter, nor between ITT and PP analyses for any outcome.Conclusions: The topical application of SH/CS-PF is as effective, safe and well tolerated as that of PEG/PG or PEG/PG-PF. The results suggest that SH/CS-PF may lead to normalization of clinical parameters and symptom alleviation in patients treated for DED.

Efficacy of 0.1% crosslinked hyaluronic acid, coenzyme Q10 and vitamin E in the management of dry eye disease in menopause patients receiving antidepressants

PURPOSE

The purpose of this study is to test non-inferiority of a lower dose of crosslinked hyaluronic acid (CLHA) to a higher dose of carmellose eye drop in menopause patients receiving antidepressant treatments.

METHODS

This prospective, double-blind, single-center study enrolled sixty female patients. Mean age was 63.25 ± 9.13 years. We examined patients with Schirmer I, breakup time (TBUT) and the ocular surface disease index (OSDI) at the first visit. Tear A eyedrops were formulated with crosslinked hyaluronic acid, coenzyme Q10 and vitamin E. Control tear B was formulated with carmellose sodium. Posology was two and five times, respectively.

RESULTS

After 2 months of treatment, the tear A obtained 14.12 ± 7.47 score points for OSDI (t = 11.74, p < 0.01), and tear B obtained 19.46 ± 10.03 score points (t = 7.59, p < 0.01). The tear A obtained 13.77 ± 7.78 score points for Schirmer test (t = 0.88, p > 0.05), and tear B obtained 14.20 ± 8.62 score points (t = 2.92, p < 0.01). The tear A obtained 8.30 ± 2.08 s for TBUT (t = 15.50, p < 0.01), and tear B obtained 7.23 ± 2.40 s (t = 8.79, p < 0.01).

CONCLUSION

Lower total daily dose of crosslinked hyaluronic acid eyedrops obtained similar efficacy results in terms of tear stability and subjective dry eye sensation than higher carmellose total daily dose. A lower total daily dose of crosslinked eyedrops was sufficient to achieve better dry eye disease management compared to carmellose.

Safety and Efficacy of a Preservative-Free Artificial Tear Containing Carboxymethylcellulose and Hyaluronic Acid for Dry Eye Disease: A Randomized, Controlled, Multicenter 3-Month Study

Purpose

To compare the efficacy and safety of an artificial tear combining the polymers carboxymethylcellulose (CMC) and hyaluronic acid (HA), to a formulation of CMC alone in subjects with dry eye.

Methods

A preservative-free artificial tear (CMC-HA) was compared with an existing artificial tear (CMC). Subjects with mild-to-severe signs and symptoms of dry eye were enrolled in this double-masked, randomized, multicenter trial, and dosed at least twice daily for 90 days, with follow-up visits at Days 7, 30, 60, and 90. Ocular Surface Disease Index (OSDI) was the primary outcome measure. Secondary outcome measures were tear break-up time (TBUT), ocular surface staining, Schirmer test with anesthesia, and visual analog scale (VAS) scores of dry eye symptom severity and formulation acceptability. Safety measures included adverse events, biomicroscopy, and visual acuity.

Results

A total of 460 subjects were enrolled across 45 sites (38 in Europe; 7 in Australia), of whom 454 were randomized to receive treatment. The per-protocol (PP) population consisted of 394 subjects, 364 (92.4%) of whom completed the study. In the PP population, the mean ± SD change from baseline in OSDI score at the primary timepoint, Day 90, was −16.9±17.5 for CMC-HA and −16.0±16.1 for CMC. CMC-HA was non-inferior to CMC based upon a confidence interval method. Both treatments significantly improved (P<0.001) OSDI, symptom VAS scores, TBUT, and ocular surface staining from baseline at all follow-up visits, with minimal differences between groups. Greater reduction of overall ocular pain/discomfort was reported in subjects using CMC-HA versus CMC (P=0.048). Approximately 10% of subjects in each group reported treatment-related adverse events of generally mild to moderate severity.

Conclusion

The new CMC-HA formulation was effective and well tolerated, and demonstrates a greater potential for symptom relief compared with CMC. These data support implementation of this formula for the management of dry eye patients.

Hyaluronic Acid: The Influence of Molecular Weight on Structural, Physical, Physico-Chemical, and Degradable Properties of Biopolymer

Hyaluronic acid, as a natural linear polysaccharide, has attracted researchers' attention from its initial detection and isolation from tissues in 1934 until the present day. Due to biocompatibility and a high biodegradation of hyaluronic acid, it finds wide application in bioengineering and biomedicine: from biorevitalizing skin cosmetics and endoprostheses of joint fluid to polymeric scaffolds and wound dressings. However, the main properties of aqueous polysaccharide solutions with different molecular weights are different. Moreover, the therapeutic effect of hyaluronic acid-based preparations directly depends on the molecular weight of the biopolymer. The present review collects the information about relations between the molecular weight of hyaluronic acid and its original properties. Particular emphasis is placed on the structural, physical and physico-chemical properties of hyaluronic acid in water solutions, as well as their degradability.

Atorvastatin-loaded solid lipid nanoparticles as eye drops: proposed treatment option for age-related macular degeneration (AMD)

Statins, widely prescribed for cardiovascular diseases, are also being eyed for management of age-related macular degeneration (AMD). Poor bioavailability and blood-aqueous barrier may however limit significant ocular concentration of statins following oral administration. We for the first time propose and investigate local application of atorvastatin (ATS; representative statin) loaded into solid lipid nanoparticles (SLNs), as self-administrable eye drops. Insolubility, instability, and high molecular weight > 500 of ATS, and ensuring that SLNs reach posterior eye were the challenges to be met. ATS-SLNs, developed (2339/DEL/2014) using suitable components, quality-by-design (QBD) approach, and scalable hot high-pressure homogenization, were characterized and evaluated comprehensively for ocular suitability. ATS-SLNs were 8 and 12 times more bioavailable (AUC) in aqueous and vitreous humor, respectively, than free ATS. Three-tier (in vitro, ex vivo, and in vivo) ocular safety, higher corneal flux (2.5-fold), and improved stability (13.62 times) including photostability of ATS on incorporation in ATS-SLNs were established. Autoclavability and aqueous nature are the other highlights of ATS-SLNs. Presence of intact fluorescein-labeled SLNs (F-SLNs) in internal eye tissues post-in vivo application as eye drops provides direct evidence of successful delivery. Perinuclear fluorescence in ARPE-19 cells confirms the effective uptake of F-SLNs. Prolonged residence, up to 7 h, was attributed to the mucus-penetrating nature of ATS-SLNs. Graphical abstract.

Impact of a low molecular weight hyaluronic acid derivative on contact lens wettability

PURPOSE

To investigate the interaction of a novel low molecular weight hyaluronic acid derivative containing hydrophobic groups with soft contact lenses and its effect on lens hydrophilicity compared with a conventional form of hyaluronic acid.

METHODS

This investigation studied the uptake of fluorescently-labelled hyaluronic acid and a low molecular weight hyaluronic acid derivative to four types of contact lenses using fluorescent microscopy and confocal laser scanning microscopy. Further, the four lens types were used to compare efficacy in improving hydrophilicity, as well as maintenance of contact angle measurements, in commercially available multipurpose solutions that contained either hyaluronic acid, the low molecular weight hyaluronic acid derivative, or an alternative wetting agent.

RESULTS

The low molecular weight hyaluronic acid derivative was found to sorb more readily to silicone hydrogel lenses and exhibit a greater accumulation over time than conventional hyaluronic acid. Multipurpose solutions containing the low molecular weight hyaluronic acid derivative showed an increase in lens hydrophilicity through decreases in contact angle measurements when compared with those obtained from lenses treated with multipurpose solutions containing conventional hyaluronic acid or alternative wetting agents. This increase in lens hydrophilicity associated with the low molecular weight hyaluronic acid derivative was also maintained over multiple cycles in phosphate buffered saline, while alternative solutions with conventional hyaluronic acid did not.

CONCLUSION

Overall, lens treatment using a low molecular weight hyaluronic acid derivative-based solution lead to improved in vitro lens hydrophilicity.

Dry Eye and Dry Nose Caused by the Effect of Allergic Rhinitis on Tear and Nasal Secretion Osmolarity

OBJECTIVE

Allergic rhinitis is a type 1 hypersensitivity reaction of immunoglobulin E in the rhino-ocular mucosa. This study was planned to demonstrate in patients with allergic rhinitis to evaluate changes in tear, nasal secretions, and blood osmolarity compared to healthy individuals.

METHOD

Forty allergic rhinitis patients, 25 patients with acute upper respiratory tract infections, and 26 healthy participants were included in the study. Positive patients with allergic symptoms and skin prick test results were included in the allergic rhinitis group. Tear, nasal secretion, and blood osmolarity values were examined for the 3 groups.

RESULT

In patients with allergic rhinitis, tear and nasal secretion osmolarity values were significantly higher in patients with acute upper respiratory tract infections and those of the healthy participants (P = .001, P = .038). In blood osmolarity measurements, there was no statistical difference between the groups (P = .489). In patients with allergic rhinitis, Schirmer test results were significantly shorter than patients who had acute upper respiratory tract infection and those of the healthy participants (P = .001, P = .001). Patients with allergic rhinitis and acute upper respiratory tract infections had significantly shorter Schirmer test results than in healthy participants (P = .001, P = .001).

CONCLUSION

Tear osmolarity was increased in allergic rhinitis patients, and this was thought to lead to dry eye findings. In the presence of allergic rhinitis, nasal secretions were found more hyperosmolar than tears. Nasal secretion osmolarity was higher in allergic rhinitis patients than in patients with acute upper respiratory tract infections and control group.

Schirmer Tear Test Value and Corneal Lesions' Incidence during General Anesthesia for Non-Ophthalmic Surgery in Non-Brachycephalic Dogs: A Pilot Study Comparing Three Different Lubricant Eye Drop Formulations

Aim of this blinded, prospective, randomized clinical study was to compare three different lubricant eye drops (LED) in healthy adult dogs undergoing general anaesthesia (GA) for non-ophthalmic surgery. Tear production rate was monitored by means of Schirmer tear test-1 (STT-1), and incidence of post-operative corneal abrasions/ulcerations was detected by corneal staining. A complete ophthalmic examination was performed before premedication, at extubation time and 24 h after GA in twenty-five non-brachycephalic dogs (fifty eyes) undergoing elective orthopaedic or spinal surgery procedures. Dogs were randomly allocated to one of three groups receiving as prophylactic LED either carmellose sodium (GC), or 1% hyaluronic acid (GH), or 0.25% hyaluronic acid (GL). In each eye STT-1 was repeated every hour during GA, before instilling one drop of the assigned LED. In all groups STT-1 values drastically decreased during GA, while 24 h later nine eyes (18%) had STT-1 values lower than 15 mm/minute. All of the three formulations tested were fully effective in preventing corneal ulceration (0% in all groups), while 10% of eyes reported superficial de-epithelialization. Fluorescein staining demonstrated that hourly prophylactic LED application prevented exposure keratopathy during general anesthesia in 90% of the eyes in non-brachycephalic dogs.

Physicochemical Properties of Hyaluronic Acid-Based Lubricant Eye Drops

PURPOSE

To assess the physicochemical properties of hyaluronic acid (HA)-based artificial tears.

METHODS

The average molecular weight (MW) and polydispersion index (PDI) of HA in 18 commercially available artificial tears were determined by light scattering/high-performance liquid chromatography. Osmolality, pH, viscosity, and sodium concentration were determined using an osmometer, pH meter, rheometer, and inductively coupled plasma mass spectrometer, respectively.

RESULTS

The MW of HA varied considerably between formulations. The PDI was >2.0 in two formulations (2.28 and 4.94), suggesting the presence of a copolymer and/or HA size variability. Three formulations exhibited viscosity exceeding the blur threshold at different shear rates. Viscosity at low shear rates was generally highest in formulations containing high-MW HA. Correlations were found between observed viscosity and a predictive/calculated value, except for four copolymer-containing formulations, and osmolality (range, 154-335 mOsm/kg) and sodium concentration (range, 22-183 mM), with two exceptions. Compared with organic osmolytes, adding sodium decreased viscosity, particularly at lower shear rates.

CONCLUSIONS

In the context of the literature, our findings suggest that for most patients with dry eye disease, the ideal HA-based artificial tear should include high-MW HA with a low PDI and exhibit enhanced viscosity at low shear rate (without exceeding the blur threshold). The inclusion of synergistic copolymers and a low sodium concentration may increase viscosity, but whether any of these physicochemical properties or correlations can predict clinical efficacy will require further investigation.

TRANSLATIONAL RELEVANCE

Understanding the properties of HA-based artificial tears will support the development of unique formulations that target specific ocular surface conditions.

Physicochemical Properties of Hyaluronic Acid-Based Lubricant Eye Drops

PURPOSE

To assess the physicochemical properties of hyaluronic acid (HA)-based artificial tears.

METHODS

The average molecular weight (MW) and polydispersion index (PDI) of HA in 18 commercially available artificial tears were determined by light scattering/high-performance liquid chromatography. Osmolality, pH, viscosity, and sodium concentration were determined using an osmometer, pH meter, rheometer, and inductively coupled plasma mass spectrometer, respectively.

RESULTS

The MW of HA varied considerably between formulations. The PDI was >2.0 in two formulations (2.28 and 4.94), suggesting the presence of a copolymer and/or HA size variability. Three formulations exhibited viscosity exceeding the blur threshold at different shear rates. Viscosity at low shear rates was generally highest in formulations containing high-MW HA. Correlations were found between observed viscosity and a predictive/calculated value, except for four copolymer-containing formulations, and osmolality (range, 154-335 mOsm/kg) and sodium concentration (range, 22-183 mM), with two exceptions. Compared with organic osmolytes, adding sodium decreased viscosity, particularly at lower shear rates.

CONCLUSIONS

In the context of the literature, our findings suggest that for most patients with dry eye disease, the ideal HA-based artificial tear should include high-MW HA with a low PDI and exhibit enhanced viscosity at low shear rate (without exceeding the blur threshold). The inclusion of synergistic copolymers and a low sodium concentration may increase viscosity, but whether any of these physicochemical properties or correlations can predict clinical efficacy will require further investigation.

TRANSLATIONAL RELEVANCE

Understanding the properties of HA-based artificial tears will support the development of unique formulations that target specific ocular surface conditions.

The Effects of Rebamipide 2% Ophthalmic Solution Application on Murine Subbasal Corneal Nerves After Environmental Dry Eye Stress

Rebamipide ophthalmic solution is a mucin secretagogue which is an important therapeutic agent in the treatment of dry eye. It has been noted that dry eye in office workers is associated with a decrease in secretory mucin. This study aimed to evaluate the effects of 2% rebamipide ophthalmic solution in mice subjected to environmental dry eye stress (EDES), which mimics the conditions of office workers. Thirty eyes from thirty BALB/c mice (eight-week-old males) were divided into three treatment groups: artificial tear (vehicle), 2% rebamipide ophthalmic solution, and 0.1% hyaluronic acid (HA) ophthalmic solution. After four days of pretreatment, mice were exposed to EDES for three days. The corneal subbasal nerve and inflammatory cells were then examined using in vivo confocal microscopy. Following EDES exposure, the lissamine green staining score was significantly lower and corneal sensitivity was more preserved in the 2% rebamipide group than in the HA group. In addition, the subbasal nerve fiber density was significantly higher and the DC density was significantly lower in the 2% rebamipide group than in the HA group. Overall, the topical rebamipide ophthalmic solution showed more favorable therapeutic effects when compared to the HA ophthalmic solution in a mouse model of EDES, likely owing to its anti-inflammatory and neuroprotective effects.

Assessment of Phosphate and Osmolarity Levels in Chronically Administered Eye Drops

Objectives

To assess phosphate and osmolarity levels of chronically administered eye drops commercially available in Turkey.

Materials and Methods

A total of 53 topical eye drops including 18 antiglaucoma drugs, 4 nonsteroidal anti-inflammatory drugs (NSAIDs), 10 corticosteroids, 7 antihistaminics, and 14 artificial tears identified using the Vademecum Modern Medications Guideline (2018) were included in the study. Phosphate levels were assessed using Roche Cobas C501 analyzer (Roche Diagnostics GmbH, Mannheim, Germany) and the respective kits. Osmolarity was assessed using Vescor Vapro 5600 vapor pressure osmometer (Sanova Medical Systems, Vienna, Austria). Mean phosphate and osmolarity levels were obtained after averaging three measurements. Eye drops were categorized as isoosmolar, hypoosmolar and hyperosmolar based on physiologic tear osmolarity range (296.5±9.8 mOsm/L).

Results

The highest phosphate concentration was found in the antiglaucoma group (20.3±35.4 mmol/L), followed by antihistaminics (17.3±17.9 mmol/L), corticosteroids (15.2±19.1 mmol/L), artificial tears (0.8±1.0), and NSAIDs (0.04±0.08). Percentage of medications in the hyperosmolar category was highest in the NSAI group (75%), followed by antihistaminics (43%), corticosteroids (20%), and antiglaucoma drugs (19%). Nearly all of the artificial tear formulations were in the hypoosmolar (71%) or isoosmolar (21%) categories.

Conclusion

Approximately 40% of glaucoma medications and approximately 60% of corticosteroid and antihistaminic medications had a phosphate concentration higher than the physiologic tear phosphate level (1.45 mmol/L).

Efficacy and safety of bromfenac 0.09% and sodium hyaluronate 0.4% combination therapy, versus placebo in patients with pterygium I-III for clinical signs on ocular inflammation

Purpose: This study evaluated the clinical efficacy and safety of bromfenac 0.09%, sodium hyaluronate 0.4% (SH) combination therapy, versus placebo and SH in a clinical model of pterygium I–III.

Methods: A total of 166 eyes (99 patients) with pterygium grade I–III were randomized to bromfenac 0.09% ophthalmic solution+SH 0.4% or placebo+SH 0.4%. This was a Phase IV, prospective, parallel, double-masked, multicenter clinical trial. One drop of bromfenac or placebo was instilled two times a day (BID) for 20 days, both groups accompanied treatments with one drop of SH three times a day (TID). The primary efficacy endpoints were the conjunctival hyperemia and the Ocular Surface Disease Index (OSDI) score. Other results measured included burning, foreign body sensation, and photophobia. The safety was assessed by the tear break-up time (TBUT), visual acuity (VA), IOP, lissamine green, fluorescein stains, and the incidence of adverse events (AEs).

Results: Compared with baseline, there was a significant reduction in the conjunctival hyperemia (p=0.0001) and OSDI score in both groups (p=0.0001). There was a significant improvement in ocular symptomatology for both, placebo/SH and bromfenac/SH groups (p=0.0001), the decrement in the ocular burning was 41.1% vs 24.6%, the foreign body sensation was 31.5% vs 36.2% and, for photophobia was 23.3% vs 30.5%, respectively. A statistically significant difference was observed in TBUT for bromfenac/SH (p=0.045), at day 20. There were no significant alterations in IOP (p=0.068) or VA (p=0.632). Similar improvements were observed in the fluorescein and green lissamine staining. Finally, the incidence of AE was similar between groups.

Conclusion: The treatment with bromfenac 0.09% ophthalmic solution and SH 0.4% combination therapy for 3 weeks reduced clinical signs, in patients with pterygium I–III. The results suggest that bromfenac 0.09% can improve the symptomatology, reduce the presentation of clinical signs associated with superficial ocular inflammation.

Changes in conjunctival epithelial cells after treatment with 0.2% xanthan gum eye drops in mild-moderate dry eye

PURPOSE

To study the effects of xanthan gum eye drops on the ocular surface and conjunctival cytology of patients with mild-moderate dry eye.

METHODS

This prospective, double-masked, controlled trial included 30 patients (age > 60 and Ocular Surface Disease Index score >12 and <33), divided into two groups of 15 subjects and treated with 0.2% xanthan gum eye drops (group 1) or 0.5% carboxymethylcellulose (group 2) qid. After a run-in period with saline qid, patients were evaluated by Ocular Surface Disease Index questionnaire, clinical assessment, and impression cytology at baseline (T0) and after 1 month (T1). For impression cytology, cellularity, cell-to-cell contacts, nucleus/cytoplasm ratio, chromatin aspect, goblet cells distribution, keratinization, and the presence of inflammatory cells were considered. Parameters were scored from 0 (no alterations) to 3 (evident alterations). For statistical analysis, Student's t-test, Wilcoxon rank-sum test, and Mann-Whitney U-test were used.

RESULTS

Clinically, after 1 month of treatment, group 1 showed an improvement of corneal stain (T0 = 1.1 ± 1.4; T1 = 0.5 ± 0.7; p = 0.03) and a reduction of Schirmer I test (T0 = 9.8 ± 6.1; T1 = 5.9 ± 4.1; p = 0.001). In group 2, no differences were found between T0 and T1 for all the clinical tests. For impression cytology, in group 1 cellularity (T0 = 0.6 ± 0.5; T1 = 0.3 ± 0.5; p = 0.05), chromatin aspect (T0 = 1.2 ± 0.4; T1 = 0.8 ± 0.5; p = 0.01), keratinization (T0 = 1 ± 0.7; T1 = 0.5 ± 0.5; p = 0.03), and total score (T0 = 5.8 ± 1.3; T1 = 3.6 ± 1.7; p = 0.003) were significantly ameliorated, while in group 2 only total score improved significantly (T0 = 5 ± 1.4; T1 = 4.3 ± 1.5; p = 0.01). The comparison between groups showed significant amelioration for keratinization in group 1 at T1 (p = 0.02).

CONCLUSION

The treatment with xanthan gum, a molecule with anti-oxidant and mucoadhesive properties, ameliorated conjunctival epithelium of mild-moderate dry eye patients better than carboxymethylcellulose.

The Effect of Periocular Fatty Acids and 0.15% Hyaluronate Eye Drops Application on Keratoconjunctivitis Sicca in Dogs: An Exploratory Study

The aim of this exploratory study was to evaluate the efficacy of a periophthalmic cream of a pool of fatty acids (FAG®) in association with 0.15% hyaluronate eye drops in alleviating the clinical symptoms of keratoconjunctivitis sicca (KCS) in a case series of dogs. The study was conducted on 10 dogs diagnosed with idiopathic KCS. All dogs had been previously treated with topical tobramycin alone, which had been ineffective in improving clinical signs. The affected eyes were treated with 2 applications daily of a periophthalmic cream of FAG® and 1 drop 3 times a day of 0.15% of hyaluronate eye drops for 8 weeks. Schirmer tear test I (STT I) values were recorded and ocular signs (conjunctival hyperemia, ocular discharge, corneal opacity, vascularization and pigmentation, and discomfort level) were collected, scored on a 3-point scale (grade 0, grade 1, and grade 2). Differences between scores and STT data recorded at baseline and at 8 weeks of therapy were statistically analysed. The effect of treatment was pronounced (increase in STT values by more than 4 mm/min, no signs of inflammation) in 8/18 eyes; moderate (increase in STT values of 3-4 mm/min or mild improvement in signs of corneal/conjunctival inflammation) in 3/18 eyes; and unsatisfactory in 7 of 18 eyes. Median of STT values significantly improved compared with baseline levels, while statistically significant decreases in clinical-sign scores of conjunctival hyperemia, ocular discharge, and discomfort were recorded. However, in moderate and advanced stages, reduction of neovascularization or corneal pigmentation was not observed throughout the treatment period. No noticeable adverse reactions were recorded. Preliminary results indicate that the application of periocular FAG and topical 0.15% hyaluronate eye drops may be a suitable treatment for KCS in dogs in selected cases. A larger comparative study is necessary to further confirm these findings.

Guiding the Design of Organic Photocatalyst for PET-RAFT Polymerization: Halogenated Xanthene Dyes

By examining structurally similar halogenated xanthene dyes, this study establishes a guiding principle for resolving structure-property- performance relationships in the photocontrolled PET-RAFT polymerization system (PET-RAFT: photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer). We investigated the effect of the halogen substituents on the photophysical and electrochemical properties of the xanthene dyes acting as photocatalysts and their resultant effect on the performance of PET-RAFT polymerization. Consideration of the structure- property-performance relationships allowed design of a new xanthene photocatalyst, where its photocatalytic activity (oxygen tolerance and polymerization rate) was successfully optimized for PET-RAFT polymerization. We expect that this study will serve as a theoretical framework in broadly guiding the design of high performance photocatalysts for organic photocatalysis.

In Vitro Evaluation of Hybrid Cooperative Complexes of Hyaluronic Acid as a Potential New Ophthalmic Treatment

PURPOSE

The purpose of this in vitro study was to assess the potential benefits of eye drops based on hybrid cooperative complexes (HCCs) obtained from high and low molecular weight hyaluronic acid (HA).

METHODS

Rheological measurements were performed to adjust the HCC concentration toward optimal resistance to drainage from the ocular surface. The viscosity and mucoadhesion profiles of the optimized preparation were derived. Primary porcine corneal epithelial cells were used for biological studies. Cells were exposed to dehydration after being pretreated with the HCC solution, and protection from desiccation was evaluated using cell viability assays. Time-lapse experiments were carried out to evaluate the ability of the HCC preparation to promote corneal wound healing. The characterization studies were performed in comparison with a control HA solution representative of commercial HA-based products.

RESULTS

The HCC formulation is able to deliver twice the amount of biopolymer compared with conventional products while avoiding discomfort due to excessive viscosity. The viscosity and mucoadhesion profiles allowed the authors to predict the longer in vivo retention and, therefore, an improved HCC formulation bioavailability. The new preparation also proved superior in protecting porcine corneal epithelial cells from desiccation and in hastening corneal cell wound repair in vitro.

CONCLUSIONS

The results suggest that the developed formulation may be a promising topical ophthalmic medical treatment.

Tear Film Osmolarity in Subjects with Acute Allergic Rhinoconjunctivitis

BACKGROUND/AIM

Acute allergic rhinoconjuctivitis is the most common form of ocular allergies. The pathogenetic mechanisms are based on an immunoglobulin E (IgE)-mediated hypersensitivity reaction. On the other hand, tear osmolarity has been suggested to be an index of ocular surface damage and inflammation. These data were the motive to investigate the levels of tear osmolarity in subjects with acute allergic rhinoconjuctivitis, before and after administration of artificial tears.

PATIENTS AND METHODS

Forty-five subjects with acute allergic rhinoconjuctivitis were randomly divided into three groups, based on the type of artificial tears that they received: Group A (Thera tears), Group B (Wet therapy) and Group C (Tears Naturale free). The eye drops were administered six times a day for 60 days and all subjects underwent grading of subjective symptoms and clinical examination at baseline and at the end of the treatment.

RESULTS

The diagnosis of severe eye disease, which was based on ocular surface disease index (OSDI; Allergan, Inc, Irvine, CA, USA) and tear osmolarity values, concerned all patients at baseline. Although the administration of artificial tears significantly ameliorated the symptoms and the ocular variables in all groups, the results were better in the first group. Tear osmolarity was strongly and negatively correlated with tear film breakup time (BUT) and Schirmer I test at 2 months. Contrariwise, symptoms were eliminated, when tear osmolarity was decreased.

CONCLUSION

Acute allergic rhinoconjuctivitis is characterized by tear hyperosmolarity, which can be rehabilitated with the administration of hypotonic artificial tears.

Efficacy of eyedrops containing cross-linked hyaluronic acid and coenzyme Q10 in treating patients with mild to moderate dry eye

PURPOSE

Dry eye disease (DED) is a common condition causing substantial burden. A randomized, controlled, single-masked study was performed in 40 patients with mild to moderate DED to evaluate the efficacy and safety of a collyrium based on crosslinked hyaluronic acid (XLHA) with coenzyme Q10 (CoQ10).

METHODS

Enrolled subjects were divided into 2 groups: group A, treated with XLHA + CoQ10; and group B, treated with hyaluronic acid (HA). Eyedrops were administered 4 times daily for 3 months. The Ocular Surface Disease Index (OSDI) questionnaire, tear break-up time (TBUT), corneal and conjunctival staining, and meibomian gland assessment (MGD) were evaluated; furthermore, corneal aesthesiometry, in vivo corneal confocal microscopy, visual acuity, intraocular pressure (IOP), and fundus examination were performed.

RESULTS

At the end of treatment, OSDI score significantly decreased in groups A and B (p<0.01 and p<0.05, respectively); the decrease was significantly higher in group A. Corneal staining decreased in both groups, with lower scores in group A. The MGD was significantly ameliorated in group A patients. No differences were found for corneal aesthesiometry or TBUT. Epithelial cell reflectivity was significantly reduced only in group A. For keratocytes and stromal matrix parameters, there was a significant improvement in group A. No changes were found for visual acuity, IOP, or fundus examination.

CONCLUSIONS

The XLHA + CoQ10 treatment showed greater effectiveness in DED compared to HA alone, probably due to the longer permanency on ocular surface and the antioxidant activity of CoQ10. Therefore, XLHA + CoQ10 eyedrops could represent a new possibility in dry eye treatment.