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

Allergic Conjunctivitis Management: Update on Ophthalmic Solutions

PURPOSE OF REVIEW

The aim of this review, is to present an updated revision of topical management of SAC and PAC, based on the available scientific evidence and focused on the impact of ophthalmic solution formulations on eye surface.

RECENT FINDINGS

Physicians treating ocular allergy should be aware of tear film and tear film disruption in SAC and PAC, and how eye drop composition and additives affect the physiology of the allergic eye. Seasonal and perennial allergic conjunctivitis (SAC and PAC) are the most frequent causes of ocular allergy (OA), and both conditions are underdiagnosed and undertreated. SAC and PAC are immunoglobulin E (IgE)-mediated hypersensitivity reactions. The additional tear film disruption caused by the release of inflammatory mediators increases and exacerbates the impact of signs and symptoms and may trigger damage of the ocular surface. Comorbidities are frequent, and dry eye disease in particular must be considered. Clinical guidelines for the management of SAC and PAC recommend topical therapy with antihistamines, mast cells stabilizers or dualaction agents as first-line treatment, but care should be taken, as many medications contain other compounds that may contribute to ocular surface damage.

Update on Dry Eye Disease Treatment: Evidence From Randomized Controlled Trials

ABSTRACT

Although the ultimate goal of dry eye disease (DED) management is to restore the ocular surface and tear film homeostasis and address any accompanying symptoms, addressing this is not an easy task. Despite the wide range of current treatment modalities targeting multiple aspects of DED, the available DED management literature is quite heterogeneous, rendering evaluation or comparison of treatment outcomes hard or almost impossible. There is still a shortage of well-designed, large-scale, nonsponsored, randomized, controlled trials (RCTs) evaluating long-term safety and efficacy of many targeted therapies individually or used in combination, in the treatment of identified subgroups of patients with DED. This review focuses on the treatment modalities in DED management and aims to reveal the current evidence available as deduced from the outcomes of RCTs.

Determinants of adherence to treatment in patients with ophthalmic conditions

BACKGROUND

The objective of this study was to identify and determine factors associated with patients' ophthalmic adherence in common ocular conditions from randomized clinical trials (RCT).

RESEARCH DESIGN METHODS

A univariate analysis with proportions, a bivariate analysis using polychoric correlations, and logistic regression (LR) models were used. The collected dataset was made up of records from RCT. Using three validated LR models, factors were identified and ranked based on their adjusted odds ratio and their statistical significance to adherence.

RESULTS

A total of 1,087 valid patients were included in this analysis, of which 88.96% presented adherence. All models were calibrated, had a good performance, were well specified and cost-effective using the Hosmer-Lemeshow test, metrics for class imbalance, link test approach and Akaike's criteriums, respectively.

CONCLUSION

We identified as determinants for encouraging good ophthalmic adherence the adverse events presented, duration of the study, female sex, and older age; other determinants such as medical condition, protocol treatment, type of treatment and disease are all risk factors for adherence. Improvements in ophthalmic adherence may be achieved by focused attention to young male patients with chronic degenerative diseases such as glaucoma or ocular hypertension (especially those who need combination therapy) and developing medications with reduced side effects.

Imaging of Escherichia coli K5 and glycosaminoglycan precursors via targeted metabolic labeling of capsular polysaccharides in bacteria

The introduction of unnatural chemical moieties into glycosaminoglycans (GAGs) has enormous potential to facilitate studies of the mechanism and application of these critical, widespread molecules. Unnatural N-acetylhexosamine analogs were metabolically incorporated into the capsule polysaccharides of Escherichia coli and Bacillus subtilis via bacterial metabolism. Targeted metabolic labeled hyaluronan and the precursors of heparin and chondroitin sulfate were obtained. The azido-labeled polysaccharides (purified or in capsules) were reacted with dyes, via bioorthogonal chemistry, to enable detection and imaging. Site-specific introduction of fluorophores directly onto cell surfaces affords another choice for observing and quantifying bacteria in vivo and in vitro. Furthermore, azido-polysaccharides retain similar biological properties to their natural analogs, and reliable and predictable introduction of functionalities, such as fluorophores, onto azido-N-hexosamines in the disaccharide repeat units provides chemical tools for imaging and metabolic analysis of GAGs in vivo and in vitro.

Efficacy and Safety of an Ophthalmic DMPC-Based Nanoemulsion in Patients with Dry Eye Disease: A Phase I/II Randomized Clinical Trial

Purpose

The goals of this study were to evaluate the safety and efficacy of an ophthalmic 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)-based nanoemulsion (Nanodrop®) in patients with dry eye disease (DED).

Methods

This was a randomized phase I/II multicentric, prospective, double-blind clinical trial. Patients (phase I: n = 25 and phase II: n = 101) were assigned to receive either PRO-176 (Nanodrop®) or Systane Balance® (control) for 29 days. Once the visits of the first 25 subjects were completed, if there were less than 20% of unexpected adverse events (AEs), related to PRO-176, recruitment was continued until the sample was completed for noninferiority (efficacy) analysis (phase II, n = 126). Efficacy endpoints were the ocular surface disease index (OSDI), tear break-up time (TBUT), epithelial defects, best corrected visual acuity (BCVA), and the incidence of expected AE.

Results

For the phase I portion of the study, there were no differences between groups regarding the incidence of AE. All related-AE symptoms in both groups were mild and expected. For the phase II subset, there was a significant reduction in OSDI scores at day 29 and noninferiority between treatments was confirmed (p=0.650, CI 95% [-8.7, 5.5]). Similar improvement was observed for TBUT although no significant intergroup differences were found (p=0.518, CI 95% [-0.08, 1.6]). There were no significant differences between treatments for epithelial staining or safety parameters.

Conclusions

Topical application of PRO-176 is as safe and effective as the controls. Both groups were clinically similar in terms of efficacy and safety. The results support the hypothesis that ophthalmic DMPC-based nanoemulsion may improve clinical parameters and symptoms in patients with DED. This trial is registered with NCT04111965.

Assessment of condition-induced changes on the ocular surface using novel methods to assess the tear film dynamics and the lipid layer

OBJECTIVES

To assess the effects of different condition-induced changes on current and novel ocular surface metrics.

METHODS

Eighty-four healthy volunteers (22.4 ± 2.6 years) participated in this study. The ocular surface and tear film response to (1) computer use, (2) contact lens insertion and (3) tear film instillation during computer use with contact lenses were assessed. Current metrics included the ocular surface disease (OSDI) questionnaire, 5-item dry eye questionnaire (DEQ-5), bulbar redness, tear meniscus height (TMH) and non-invasive keratograph break-up time (NIKBUT). Novel metrics included the lipid layer thickness obtained from the intensity of the reflected Placido disk and the speed of tear film particles post-blink.

RESULTS

Higher dry eye symptoms, TMH and bulbar redness, and lower values in metrics related to the intensity of the Placido disk pattern and to particle speed were found after the computer reading task (p < 0.036). When a contact lens was fitted, lower TMH, NIKBUT and particle speed metrics were obtained (p < 0.044). Mixed ANOVA revealed that artificial tears significantly ameliorated the effect of computer reading on OSDI, DEQ-5, NIKBUT, metrics related to the intensity of the Placido disk pattern and metrics related to particle speed (p < 0.033).

CONCLUSIONS

Computer use and contact lens wear worsened dry eye signs and symptoms, but artificial tears ameliorated this effect. Newly developed methods can serve as a tool to detect changes in the tear film triggered by different ocular surface-disturbing conditions.

Oxidized chondroitin sulfate eye drops ameliorate the prognosis of fungal keratitis with anti-inflammatory and antifungal effects

Fungal keratitis (FK) is a refractory ophthalmic disease that can result in vision impairment and even blindness due to the severe fungal invasiveness and excessive inflammatory response. Therefore, antifungal treatment combined with local immunosuppressive therapy is regarded as the most effective strategy to improve the clinical outcome of FK. Oxidized polysaccharides with aldehyde groups possess obvious inhibitory activity towards microorganisms. Herein, we use chondroitin sulfate (CS), a recognized anti-inflammatory biopolysaccharide, to prepare oxidized chondroitin sulfate (OCS) via sodium periodate (NaIO₄) oxidation for the treatment of FK. The chemical structure of OCS was characterized by FTIR, ¹H NMR, and XPS, revealing that the O-dihydroxy in the D-glucuronic acid unit of CS was selectively broken by NaIO₄, forming active aldehyde groups. The introduction of aldehydes not only retains the anti-inflammatory activity but also confers OCS with antifungal property. In vitro antifungal experiments showed that OCS inhibits the growth, represses the biofilm formation and alters the membrane integrity of A. fumigatus. The toxicity of OCS was evaluated by cytotoxicity tests (CCK-8) and the Draize eye test in vitro and in vivo. qRT-PCR confirmed that OCS had similar anti-inflammatory activity as CS. In mice with A. fumigatus keratitis, OCS versus CS or PBS showed an excellent therapeutic effect, characterized by a lower corneal inflammation score, less fungal load, reduced neutrophil recruitment, and the downregulated expression of pro-inflammatory factors. Our findings demonstrate that OCS improves the prognosis of A. fumigatus keratitis in mice by inhibiting the growth of fungi, reducing the recruitment of neutrophils and inhibiting the inflammatory response. It provides innovative ideas for the development and application of OCS in medicine and biomaterials fields.

Dry eye syndrome: comprehensive etiologies and recent clinical trials

Dry eye syndrome (DES) is multifactorial and likely to be a cause of concern more so than ever given the rapid pace of modernization, which is directly associated with many of the extrinsic causative factors. Additionally, recent studies have also postulated novel etiologies that may provide the basis for alternative treatment methods clinically. Such insights are especially important given that current approaches to tackle DES remains suboptimal. This review will primarily cover a comprehensive list of causes that lead to DES, summarize all the upcoming and ongoing clinical trials that focuses on treating this disease as well as discuss future potential treatments that can improve inclusivity.

Effects of Calf Blood-Deproteinized Extract Ophthalmic Gel Combined with Sodium Hyaluronate Eye Drops on Conjunctival Hyperemia Score and Tear Film Stability in Patients with Dry Eye

Objective

The aim of this paper is to research the impact of calf blood-deproteinized extract ophthalmic gel combined with sodium hyaluronate eye drops on conjunctival hyperemia score and tear film stability in patients having dry eye.

Methods

144 patients having dry eye disease who were hospitalized from July 2018 to July 2021 were chosen as the research targets, which were composed of the control group and research group on the basis of the sequences of hospitalization, and each has 72 cases. The sodium hyaluronate eye drops were gained in the control one. In accordance with the control one, the study ones were given the combined treatment with eye drops of sodium hyaluronate. Treatment of calf blood-deproteinized extract ophthalmic gel, the scores of conjunctival hyperemia, tear film stability, visual function, curative effect, and their adverse reactions were observed and made comparisons among the two groups.

Results

After the treatments of 2 weeks and later 1 month, the numerical values of the conjunctival hyperemia were fewer in the categories which had been mentioned above, and in contrast with the control one (P < 0.05), the numerical values of the conjunctival hyperemia in the study one were distinctly fewer. The data of SIt, BUT, and the heights of the central tear river of the lower eyelid were higher than those before cure. In comparison with the control one, the FL of the study one was distinctly lower, and the heights of SIt, BUT, and the central tear river of the lower eyelid were obviously better than the control one (P < 0.05). After therapy, the visual contrast sensitivity of the patients in two categories at 6.4 c/d and 12c/d increased in comparison with those before treatment, and the visual contrast sensitivity of the study group at 6.4 c/d and 12c/d was apparently higher than the data of control one (P < 0.05); the effective rate of treatment in the study one was 97.22%, which had a higher situation than the control one, 88.89% (P < 0.05); the probability of occurrence of the negative events in the study one after treatment was 4.17%, which was distinctly below the control one, 15.28% (P < 0.05).

Conclusion

In order for the treatments of patients having dry eye disease, the use of calf blood-deproteinized extract ophthalmic gel having the combinations with eye drops of sodium hyaluronate can enhance the extent of visual impairment and conjunctival hyperemia with effect and improve the stability of tear film, with significant safety and high efficiency.

Heterologous production of chondroitin

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Chondroitin sulfate (CS) is a glycosaminoglycan with a growing variety of applications.

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CS can be produced from microbial fermentation of native or engineered strains.

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Synthetic biology tools are being used to improve CS yields in different hosts.

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Integrated polymerization and sulfation can generate cost-effective CS.

Chondroitin sulfate (CS) is a glycosaminoglycan with a broad range of applications being a popular dietary supplement for osteoarthritis. Usually, CS is extracted from animal sources. However, the known risks of animal products use have been driving the search for alternative methods and sources to obtain this compound. Several pathogenic bacteria naturally produce chondroitin-like polysaccharides through well-known pathways and, therefore, have been the basis for numerous studies that aim to produce chondroitin using non-pathogenic hosts. However, the yields obtained are not enough to meet the high demand for this glycosaminoglycan. Metabolic engineering strategies have been used to construct improved heterologous hosts. The identification of metabolic bottlenecks and regulation points, and the screening for efficient enzymes are key points for constructing microbial cell factories with improved chondroitin yields to achieve industrial CS production. The recent advances on enzymatic and microbial strategies to produce non-animal chondroitin are herein reviewed. Challenges and prospects for future research are also discussed.

Ophthalmic Solution Safety Profile: Active Surveillance of a Sodium Hyaluronate/Chondroitin Sulfate Combination in Peruvian Population

Background

Sodium hyaluronate/chondroitin sulfate fixed combination plays an essential role in the treatment of keratoconjunctivitis sicca, a multifactorial disease accompanied by ocular symptoms like alteration of the tear film. Despite low or no absorption of such drugs, these can cause secondary effects. An essential tool in the study of medication behavior is active pharmacovigilance. Unlike spontaneous reporting pharmacovigilance, this tool allows an appraisal of adverse drug reactions (ADRs)’ real incidence, a higher capacity to identify safety signals, the relationship with concomitant drugs and pathologies prevalent in the study population. This study aimed to evaluate the safety profile and identify and/or assess adverse reactions in an uncontrolled population.

Methods

Active pharmacovigilance by Drug Event Monitoring was performed. A total of 3 follow-up calls were made for 30 days for the identification of the ADRs, tolerability (ADR severity, seriousness, long term sequelae, and duration) and the possible risks (safety signals, medical interactions) of sodium hyaluronate and chondroitin sulfate (HUM).

Results

Thirty-five ADRs were identified in the 212 patients included in the study (0.17 ADR/patient). The 35 ADRs were classified into 3 System Organ Class (SOC) groups: general disorders and administration site conditions (74.2%), eye disorders (22.9%), and nervous system disorders (2.9%); and 4 Preferred Term (PT) groups: burning sensation (74.2%), followed by blurred vision (20%), ocular pain (2.9%) and headache (2.9%). All the ADRs were categorized as mild and not serious. No statistically significant differences were found in concomitantly medications, posology and age groups.

Conclusion

Good tolerability to the solution was identified, with a low incidence of ADRs. Just the same, all the associated ADRs were consistent with the information found in HUM’s physicochemical profile and the physiopathology of DED. No unknown risks were identified, reinforcing HUM’s safety profile.