Topical preservative-free ophthalmic treatments: an unmet clinical need

Squeezability of eye drop containers used in dry eye disease management

CLINICAL RELEVANCE

Ocular lubricants are the mainstay of dry eye management and are available in a variety of formulations and bottle designs. The squeezability of ocular lubricant bottles may influence administration and compliance.

BACKGROUND

A key component for managing dry eye disease is the use of ocular lubricants. The different bottle types, each with their unique material strength and dispensing mechanism, may be challenging for patients with limited hand and pinch strength. The aim of this study was to evaluate the force required to expulse a drop from different eye drop containers used in the management of dry eye disease.

METHODS

The force, in newtons (N), required to expulse a drop from different eye drops was evaluated five times using a force gauge, and divided by bottle type, i.e. tubes, unidose, multidose with preservatives, and multidose preservative free (MDPF) bottles.

RESULTS

Sixty (n = 60) bottles were examined with 57 eye lubricants and 3 dry eye medications (cyclosporine (0.5% and 0.9%), and lifitegrast). The average force varied depending on the bottle type (tubes 4.28 ± 1.29 N; unidose 14.24 ± 4.83 N; multidose 16.62 ± 5.21 N; MDPF 26.68 ± 8.32 N, p < 0.001). Post-hoc test revealed that MDPF bottles required more force than all other bottle types (p < 0.001), and among those, the ophthalmic squeeze dispenser bottle required significantly more force (p < 0.001). Lifitegrast required more force (17.38 ± 2.13 N) than cyclosporine 0.5% (9.16 ± 0.80 N, p < 0.024) and cyclosporine 0.9% (5.68 ± 0.40 N, p < 0.001), but was not significantly different from unidose ocular lubricants (p > 0.05).

CONCLUSION

The squeezability of bottles used in dry eye disease management varies with bottle type. Hand and pinch strength should be considered when choosing products for dry eye disease management, as the squeezability of an ophthalmic drop can influence its administration and compliance.

Elucidating acceptance and clinical indications to support the rational design of drug-eluting contact lenses

The advent of drug-eluting contact lenses (DECLs) has opened up new avenues for the treatment of eye diseases. DECLs is expected to partially overcome the shortcomings of eye drops due to single-dose packaging, accurate dosing, prolonged drug elution behavior, and simplified dosing procedures. Currently, a significant proportion of the DECLs design effort has been directed towards enhancing the compatibility of contact lenses with drugs. The appropriate elution time for the drug remains unclear. Additionally, it is ambiguous for which ophthalmic diseases DECLs offers the greatest therapeutic advantage. To rationally design DECLs in practice, it is necessary to understand the acceptance of DECLs by patients and practitioners and to clarify the indications for DECLs. This review will first focus on the acceptance of DECLs by different patients and practitioners and discuss the factors that influence its acceptance. Secondly, this review presents an overview of the current effectiveness of DECLs treatments in animals and in the clinical phase, with a particular focus on the suitability of DECLs for the treatment of ophthalmic diseases. Overall, patients and practitioners expressed positive attitudes towards DECLs. However, this is related to factors such as DECLs' treatment cycle, safety, and price. In addition, DECLs has good application prospects for ocular wound healing, postoperative management, and treatment of contact lenses-related complications. Furthermore, chronic diseases such as glaucoma that necessitate long-term medication and intraocular diseases that require implants or injections represent additional potential applications for DECLs. It is hoped that this review will facilitate a deeper understanding of DECLs acceptance and indications, thereby supporting the rational design of DECLs. At the same time, this review provides a reference for the design of other drug-device combination products.

Evidence in Practice: A Review of Real-Life Studies and Clinical Experience with the Preservative-Free Tafluprost (0.0015%) and Timolol (0.5%) Fixed-Dose Combination

The preservative-free fixed-dose combination formulation of 0.0015% tafluprost and 0.5% timolol (PF tafluprost/timolol FC) is among the topical intraocular pressure (IOP)-lowering therapies commonly used second-line for the management of ocular hypertension (OHT) and open-angle glaucoma (OAG), according to recommended treatment pathways. A growing body of evidence has developed in recent years regarding efficacy, safety and tolerability outcomes with PF tafluprost/timolol FC in both randomized controlled trials (RCTs) and real-life studies. This review aims to summarize key evidence from published Phase IV trials and real-life studies to highlight those data that complement RCT findings and support implementation of evidence-informed clinical practice. Real-life efficacy and safety outcomes are discussed through the lens of common clinical scenarios that ophthalmologists may encounter in the management of OHT/OAG. Phase IV studies conducted to date have demonstrated that the majority of OHT/OAG patients insufficiently controlled on topical prostaglandin or beta-blocker monotherapy may achieve IOP reductions of ≥20% following a switch to PF tafluprost/timolol FC therapy. Statistically significant IOP reductions were reported from 4 weeks and maintained through 6 months. Real-life studies and case series data also indicated that patients with poor IOP control on maximal/complex topical regimens benefited from a step down to PF tafluprost/timolol FC therapy, achieving significant and sustained IOP reductions. A number of studies have shown improvements in tolerability and the signs and symptoms of ocular health with PF tafluprost/timolol FC therapy, both in patients stepping up from monotherapy and in those simplifying their topical regimen. Clinicians reported better treatment adherence with PF tafluprost/timolol FC compared with prior treatments, which may have been associated with enhanced patient experience regarding treatment tolerability and is likely to have contributed to the long-term IOP-lowering efficacy outcomes observed. Real-life safety data for PF tafluprost/timolol FC reflect outcomes reported in published RCTs.

A major review on punctal stenosis: Part II: Updated therapeutic interventions, complications, and outcomes

We continue our review of on punctal stenosis by providing a detailed discussion of management modalities, their complications, and outcomes. There is a significant change in the understanding of punctal and peripunctal anatomy, puncto-canalicular junction, and the lacrimal pump mechanisms. While the snip punctoplasty procedures are still practiced, there is an increasing trend toward nonincisional procedures. The nonincisional procedures in select cases appear to be equally effective as the incisional ones. Although simple to use, punctal plugs never became the mainstay of treatment because of design issues and the inability to address the coexisting canalicular stenosis. Placing stents only in the lower punctum in cases of upper and lower punctal stenosis should be discouraged, and management needs to address punctal stenosis and not which punctum is involved. Several types of stents are used in the management of punctal stenosis, mostly based on surgeon's preference. The benefits of adjuvant mitomycin C are uncertain. In view of literature on how stent biofilms can themselves cause chronic inflammation, placing them for prolonged periods should be reviewed and debated. Enhanced understanding of the molecular pathogenesis of punctal stenosis and addressing the current controversies in management would help standardize the therapeutic interventions available in the lacrimal armamentarium.

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.

Is the Advent of New Surgical Procedures Changing the Baseline Features of Patients Undergoing First-Time Glaucoma Surgery?

Background: The aim of this study was to determine if the rise in new surgical procedures for glaucoma is changing the baseline features of patients. Methods: In this retrospective study, we reviewed the baseline features of patients undergoing their first glaucoma surgery in 2011 and 2021, collecting data regarding intraocular pressure (IOP), visual field (VF) parameters, stage of disease, and the type of surgery. Results: In the study, 455 patients were included in the analysis. From these, 230 eyes had glaucoma surgery performed in 2011 (Group A) and 225 eyes in 2021 (Group B). When considering the baseline features, Group A was older than Group B (72.7 ± 10.7 and 70 ± 12.4 years; p = 0.02, respectively), and showed a significantly more advanced VF mean defect (-16.4 ± 8.8 and -13.8 ± 8.7 dB; p < 0.01, respectively) and a higher IOP (25.9 ± 6.6 and 24.9 ± 7.8 mmHg; p = 0.02, respectively). Overall, severe VF damage at the time of surgery was more frequent in Group A (74.3%) than in Group B (60.8%) (p < 0.01). The overall number of traditional glaucoma surgeries was 211 in 2011, reducing to 94 ten years later, with similar severe pre-operative VF defects. In 2021, minimally invasive bleb surgery (MIBS) represented 58% of all surgeries. Conclusions: In the last ten years, patients receiving glaucoma surgery for the first time were younger, had less severe disease, and a more contained IOP. The baseline feature modifications were probably related to the diffusion of new procedures, especially MIBS, which allowed for treating patients at an earlier stage, reserving traditional procedures for advanced cases.

A major review of punctal stenosis: Updated anatomy, epidemiology, etiology, and clinical presentation

We aim to provide a detailed and updated literature review on the epidemiology, etiology, clinical presentations, histopathology, and ultrastructural features of punctal stenosis. There are inconsistencies in the definition and staging of punctal stenosis. While advanced optical coherence tomography imaging techniques have revolutionized the way the punctum and vertical canaliculi are assessed or monitored following treatment, the planes of measurement to characterize punctum anatomy need to evolve further. The current criteria for diagnosing and grading punctal stenosis are inadequate and based on empirical clinical findings. There is increasing evidence of the role of lymphocytes and myofibroblasts in the pathogenesis of punctal stenosis. There is a need for a uniform assessment of punctal stenosis and a uniform reporting of severity that would help standardize the several management options available in the lacrimal armamentarium.

Changing from preserved, to preservative-free cyclosporine 0.1% enhanced triple glaucoma therapy: impact on ocular surface disease-a randomized controlled trial

OBJECTIVE

Halting and reversing glaucoma therapy-related ocular surface disease (GTR-OSD) will improve the success of long-term medical therapy, impacting millions of patients worldwide.

METHODS

A single-centre, masked, prospective, placebo-controlled, crossover trial of 41 well-controlled open-angle glaucoma subjects with moderate to severe GTR-OSD on preserved latanoprost and dorzolamide/timolol fixed combination (DTFC) therapy was conducted. Subjects were randomized to preservative-free (PF) tafluprost and DTFC with either placebo or cyclosporine 0.1% drops for 6 months and were then crossed over to the opposite therapy. Oxford score of ocular staining was the primary outcome; osmolarity, matrix-metalloproteinase-9 (MMP-9) testing, tear film break-up time (TFBUT), meibomian gland dysfunction (MGD), punctum evaluation, adverse events and diurnal intraocular pressure (IOP) comprised secondary outcomes.

RESULTS

GTR-OSD findings improved with PF therapy. At 6 months the triple PF with placebo group showed improvement compared to baseline in mean Oxford score (mean difference [MD]:-3.76; 95% confidence interval [CI]:-4.74 to -2.77; p < 0.001), osmolarity (MD:-21.93; 95%CI:-27.61 to -16.24 mOsm/l; p < 0.001), punctum stenosis (p = 0.008) and conjunctival hyperaemia (p < 0.001). Similar improvements occurred in the cyclosporine enhanced period, which also provided greater improvement in MMP-9 positivity (24 vs 66%; p < 0.001) and TFBUT (p = 0.022). The cyclosporine group was superior vs placebo in mean Oxford score (MD:-0.78; 95%CI:-1.40 to -0.15); p < 0.001), itchiness and objective adverse events (p = 0.034). Cyclosporine elicited more stinging vs placebo (63 vs 24%; p < 0.001). Both PF regimens reduced mean diurnal IOP more than preserved therapy (14.7 vs 15.9 mmHg; p < 0.001).

CONCLUSIONS

Changing from preserved to PF glaucoma medications improves ocular surface health and IOP control. Topical cyclosporine 0.1% further reverses GTR-OSD.

Ocular surface and glaucoma, a mutual relationship. Practical suggestions for classification and management

The chronic use of glaucoma medications could improve the development of an ocular comorbidity, the glaucoma therapy-related ocular surface disease. This could be related to the exposure of the conjunctiva to preservatives, but also active compounds such as prostaglandin analogues may improve the risk of ocular surface inflammation. Inflammation has a negative impact on tolerability and adherence to eyedrops and to the outcome of filtration surgery as well. A stratification of glaucoma patients based not only on visual field progression but also on glaucoma therapy-related ocular surface disease would be desirable for a strategic management. Early diagnosis, individualized treatment, and safe surgical management should be the hallmarks of glaucoma treatment. One of the main issues for the proper and successful management of patients is the right timing, effectiveness and safety for both medical and surgical treatment options leading to a precision medicine in glaucoma disease as the best modern treatment.

Ocular Surface Disease in Glaucoma Patients

PURPOSE

To review the most recent studies in the literature regarding the ocular surface in glaucoma patients and treatment options aimed to reduce ocular surface disease in this population.

METHODS

We performed a literature search in the electronic databases of PubMed CENT RAL, Google Scholar, EMBASE the Register of Controlled Trials, and Ovid MEDLINE using the following terms: "ocular surface", "dry eye", "glaucoma", "selective laser trabeculoplasty", "glaucoma surgery", "preservatives", "preservative free", "ocular surface disease index", "tear break up time", "MMP-9" and "conjunctival hyperemia".

RESULTS

Over the last several years, several studies have demonstrated the changes to the ocular surface in the setting of glaucoma, the best tests for markers of dry eye, and how management can be altered to help address ocular surface disease routinely or in preparation for glaucoma surgery.

CONCLUSION

Ocular surface disease in the glaucoma patient population is widely recognized. It should be addressed to maximize patient compliance and quality of life.

Challenges and concepts in the diagnosis and management of ocular graft-versus-host disease

Graft-versus-host disease (GVHD) is characterized by tissue inflammation in the host following an allogeneic hematopoietic cell transplantation (HCT). The pathophysiology is complex and only incompletely understood yet. Donor lymphocyte interaction with the histocompatibility antigens of the host plays a crucial role in the pathogenesis of the disease. Inflammation may affect multiple organs and tissues, e.g., the gastrointestinal tract, liver, lung, fasciae, vaginal mucosa, and the eye. Subsequently, alloreactive donor-derived T and B lymphocytes may lead to severe inflammation of the ocular surface (i.e., cornea and conjunctiva) and the eyelids. Furthermore, fibrosis of the lacrimal gland may lead to severe dry eye. This review focuses on ocular GVHD (oGVHD) and provides an overview of current challenges and concepts in the diagnosis and management of oGVHD. Ophthalmic manifestations, diagnostic procedures, grading of severity and recommendations for ophthalmic examination intervals are provided. Management of ocular surface disease with lubricants, autologous serum eye drops, topical anti-inflammatory agents and systemic treatment options are described based on the current evidence. Ocular surface scarring and corneal perforation are severe complications of oGVHD. Therefore, ophthalmic screening and interdisciplinary treatment approaches are highly relevant to improve the quality of life of patients and to prevent potentially irreversible visual loss.

Intravitreal Injectable Hydrogels for Sustained Drug Delivery in Glaucoma Treatment and Therapy

Glaucoma is extensively treated with topical eye drops containing drugs. However, the retention time of the loaded drugs and the in vivo bioavailability of the drugs are highly influenced before reaching the targeted area sufficiently, due to physiological and anatomical barriers of the eye, such as rapid nasolacrimal drainage. Poor intraocular penetration and frequent administration may also cause ocular cytotoxicity. A novel approach to overcome these drawbacks is the use of injectable hydrogels administered intravitreously for sustained drug delivery to the target site. These injectable hydrogels are used as nanocarriers to intimately interact with specific diseased ocular tissues to increase the therapeutic efficacy and drug bioavailability of the anti-glaucomic drugs. The human eye is very delicate, and is sensitive to contact with any foreign body material. However, natural biopolymers are non-reactive, biocompatible, biodegradable, and lack immunogenic and inflammatory responses to the host whenever they are incorporated in drug delivery systems. These favorable biomaterial properties have made them widely applicable in biomedical applications, with minimal adversity. This review highlights the importance of using natural biopolymer-based intravitreal hydrogel drug delivery systems for glaucoma treatment over conventional methods.

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

Introduction

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

Methods

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

Results

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

Conclusion

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

Physicochemical Stability of a Novel Tacrolimus Ophthalmic Formulation for the Treatment of Ophthalmic Inflammatory Diseases

Tacrolimus is an immunosuppressant used to treat a large variety of inflammatory or immunity-mediated ophthalmic diseases. However, there are currently no commercial industrial forms available that can provide relief to patients. Various ophthalmic formulations have been reported in the literature, but their stability has only been tested over short periods. The objective of this study was to evaluate the physicochemical stability of a preservative-free tacrolimus formulation (0.2 and 1 mg/mL) at three storage temperatures (5 °C, 25 °C and 35 °C) for up to nine months in a multidose eyedropper. Analyses performed were the following: visual inspection and chromaticity, turbidity, viscosity, size of micelles, osmolality and pH measurements, tacrolimus quantification by a stability-indicating liquid chromatography method, breakdown product research, and sterility assay. In an in-use study, tacrolimus quantification was also performed on the drops emitted from the eyedroppers. All tested parameters remained stable during the nine month period when the eyedrops were stored at 5 °C. However, during storage at 25 °C and 35 °C, several signs of chemical instability were detected. Furthermore, a leachable compound originating from a silicone part of the eyedropper was detected during the in-use assay. Overall, the 0.2 mg/mL and 1 mg/mL tacrolimus ophthalmic solutions were physicochemically stable for up to nine months when stored at 5 °C.

Cellulosic Polymers for Enhancing Drug Bioavailability in Ocular Drug Delivery Systems

One of the major impediments to drug development is low aqueous solubility and thus poor bioavailability, which leads to insufficient clinical utility. Around 70–80% of drugs in the discovery pipeline are suffering from poor aqueous solubility and poor bioavailability, which is a major challenge when one has to develop an ocular drug delivery system. The outer lipid layer, pre-corneal, dynamic, and static ocular barriers limit drug availability to the targeted ocular tissues. Biopharmaceutical Classification System (BCS) class II drugs with adequate permeability and limited or no aqueous solubility have been extensively studied for various polymer-based solubility enhancement approaches. The hydrophilic nature of cellulosic polymers and their tunable properties make them the polymers of choice in various solubility-enhancement techniques. This review focuses on various cellulose derivatives, specifically, their role, current status and novel modified cellulosic polymers for enhancing the bioavailability of BCS class II drugs in ocular drug delivery systems.

The treatment of glaucoma using topical preservative-free agents: an evaluation of safety and tolerability

Introduction: Preservative-free (PF) medications represent a valuable treatment strategy in the lifelong management of glaucoma. By removing preservative toxicity, PF formulations provide tangible clinical benefits to glaucoma patients worldwide. They improve tolerability and adherence, leading to a positive impact in long-term intraocular pressure (IOP) control.Areas covered: A critical review of the subject is provided, including selected evidence on the safety and tolerability of currently available topical PF formulations. Cumulative evidence confirms that topical PF medications are at least equally efficacious to their preserved equivalents. There is convincing short-term evidence for superior tolerability and safety of PF formulations compared to preserved medications. The long-term benefits and success of PF therapy requires further elucidation.Expert opinion: Successful stepwise administration of medical therapy for glaucoma remains elusive. There is a greater risk for ocular toxicity and therapy failure with preserved topical glaucoma therapy. Currently available and emerging PF therapy options potentially optimize lifelong stepwise glaucoma therapy and may enhance outcome. To avert complications from preservatives leading to poor adherence, ideally, future antiglaucoma therapy should become 100% PF. There are still key aspects of PF therapy that warrant further investigation.

In Vivo Efficacy of Contact Lens Drug-Delivery Systems in Glaucoma Management. A Systematic Review

Adherence is crucial in medical glaucoma therapy, although half of the patients skip eyedrops. In recent years alternative drug-delivery systems have been developed. One of the most promising seems the contact lens (CL). This systematic review aims to present the in vivo efficacy of different CL drug-delivery systems. A total of 126 studies were identified following a literature search adhering to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. After full-text evaluation, 19 studies about CL drug-delivery systems were included. To date, the following drug-delivery systems have been investigated in vivo: drug-soaked CL, CL with physical barriers (vitamin E), molecularly imprinted CL, CL with implants, and nanoparticle-loaded CL. Nanoparticle-loaded CL and CL with implants seem the most promising drug-delivery systems, although initial burst drug release and patient acceptance may limit their widespread use in current practice. Clinical trials are warranted to understand the role of CL as a drug-delivery system in improving glaucomatous patient care.