A comparative approach to topical cyclosporine therapy

Improved Signs and Symptoms of Dry Eye Disease for Restasis® Patients Following a Single Tearcare® Treatment: Phase 2 of the SAHARA Study

Purpose

To evaluate dry eye disease (DED) signs and symptoms six months after a single treatment with Localized Heat Therapy (LHT) (TearCare, Sight Sciences) for patients previously treated for six months with cyclosporine (0.05%) ophthalmic emulsion (CsA) BID (Restasis, Allergan).

Setting

Nineteen ophthalmic and optometric practices in 11 US states.

Design

Multicenter, cross-over, six month extension to the SAHARA randomized, controlled trial (RCT). Included patients were those randomized to CsA in Phase 1 of the SAHARA RCT.

Methods

This was the second phase of the SAHARA RCT in which, following the 6-month endpoint, all patients that had been randomized to CsA discontinued CsA and were treated with LHT and subsequently followed for an additional six months. Outcome measures at 12 months for CsA patients crossed over to LHT included TBUT, OSDI and MGSS.

Results

One hundred and sixty-one patients (322 eyes) were analyzed. Mean (SD) baseline TBUT prior to CsA was 4.4 (1.2) seconds, 5.6 (2.6) at 6 months which improved to 6.6 (3.2) and 6.1 (2.8) seconds (both P < 0.001) at 9 and 12 months (3, 6 months post LHT). Mean (SD) OSDI was 50.0 (14.9) at baseline and 34.2 (21.5) after CsA. With LHT at 6 months, this improved to 30.0 (20.6) and 31.0 (19.5) at 9 and 12 months (P = 0.162 vs month 6, P < 0.0001 vs baseline). MGSS was 7.1 (3.2) at baseline, 13.3 (8.2) at the end of CsA treatment which improved to 17.4 (8.8) and 16.1 (9.0) at 9 and 12 months; both P <0.001.

Conclusion

SAHARA showed 6-month superiority of LHT to CsA in clinical signs and non-inferiority in symptom scores. This extension shows that patients treated with CsA for 6 months can achieve meaningful additional improvement in signs and symptoms lasting for as long as 6 months following a single LHT treatment without the need for topical prescription therapy.

How Can We Best Diagnose Severity Levels of Dry Eye Disease: Current Perspectives

Dry eye disease (DED) is a common ocular condition, but the diagnosis relative to other ocular conditions and the evaluation of severity of the condition has often been difficult. This challenge can be due to clinical signs and symptoms not always correlating with each other. An understanding of the various components which create the condition, as well as the diagnostic measures used to evaluate these components, is useful to the clinician working with DED patients. This review paper will discuss traditional diagnostic options, diagnostic imaging, and Advanced Point of Care testing capabilities to determine the severity level of dry eye disease more adequately.

Cyclosporine A Delivery Platform for Veterinary Ophthalmology—A New Concept for Advanced Ophthalmology

Cyclosporine A (CsA) is a selective and reversible immunosuppressant agent that is widely used as a medication for a wide spectrum of diseases in humans such as graft versus host disease, non-infectious uveitis, rheumatoid arthritis, psoriasis, and atopic dermatitis. Furthermore, the CsA is used to treat keratoconjunctivitis sicca, chronic superficial keratitis, immune-mediated keratitis and equine recurrent uveitis in animals. The selective activity of Cyclosporine A (CsA) was demonstrated to be an immunomodulation characteristic of T-lymphocyte proliferation and inhibits cytokine gene expression. Moreover, the lipophilic characteristics with poor bioavailability and low solubility in water, besides the side effects, force the need to develop new formulations and devices that will provide adequate penetration into the anterior and posterior segments of the eye. This review aims to summarize the effectiveness and safety of cyclosporine A delivery platforms in veterinary ophthalmology.

Topical tacrolimus nanocapsules eye drops for therapeutic effect enhancement in both anterior and posterior ocular inflammation models

Tacrolimus has shown efficacy in eye inflammatory diseases. However, due to the drug lability, its formulation into a stable ophthalmic product remains a challenge. Tacrolimus-loaded nanocapsules (NCs) were designed for ocular instillation. Further, the stability and effects of the formulation were analyzed under different experimental conditions. Physicochemical characterization of the NCs revealed suitable homogeneous size and high encapsulation efficiency. Moreover, the lyophilized formulation was stable at ICH long term and accelerated storage conditions, for at least 18 and 3 months, respectively. The tacrolimus NCs did not elicit any eye irritation in rabbits after single- and multiple-dose applications. Additionally, ex vivo penetration assays on isolated porcine cornea and pharmacokinetics analyses in various rabbit eye compartments demonstrated the superiority of the NCs in retention and permeation into the anterior chamber of the eye compared to the free drug dissolved in oil. Moreover, multiple dose ocular instillation of the NCs in rats allowed high tacrolimus levels in the eye with very low plasma concentrations. Finally, the developed delivery system achieved a significant decrease in four typical inflammatory markers in a murine model of keratitis, an anterior chamber inflammation. Furthermore, these NCs, applied as eye drops, displayed clinical and histological efficacy in the mainly posterior chamber inflammation model of murine, experimental auto-immune uveitis.

Topical preservative-free ophthalmic treatments: an unmet clinical need

Introduction: The main role of preservatives in eyedrops is to ensure sterility and microbiological integrity of the drug, and to facilitate the penetration of active compounds into the eye. However, several studies documented significant toxic effects induced by preservatives, especially on the ocular surface. Consequently, most of the ophthalmic medications became progressively available in preservative-free (PF) formulations.Areas covered: We analyzed pre-clinical and clinical studies on PF eyedrops with particular attention to common chronic diseases such as dry eye and glaucoma. We discussed about the pros and cons of using PF eyedrops, in terms of efficacy, safety, and social-economic aspects.Expert opinion: There are still unresolved issues that make hard for PF medications to definitively conquer the drug market. Despite robust pre-clinical evidences of less toxicity, the low number of randomized clinical trials does not permit to state that PF eyedrops have, in clinical practice, a similar efficacy or a higher safety compared to preserved forms. These aspects limit their use to chronic diseases requiring long-term therapies with multiple daily instillations, especially in the presence of concomitant ophthalmic diseases that expose to a risk of ocular surface worsening.

Animal models of scarring control

Filtration surgery has, for the past 50 years been key in the treatment of glaucoma yet a significant issue in the long-term success of such surgery is fibrosis limiting aqueous drainage. Numerous methods have been used to reduce such scarring after filtration surgery and animal models have been important in the development of such techniques. First animal models have been central in understanding molecular and cellular changes occurring in fibrosis and thus which pathways might be valuable therapeutic. Secondly animal models have been critical in determining which of these therapies is likely to be most worthwhile. Having said that animals differ substantially from humans in the anatomy of their aqueous drainage pathways and in the mechanisms of fibrotic change. Rodents and lagomorphs vary more markedly from humans than do primates at an anatomic, biochemical and physiological level, and thus the latter might seem more appropriate as models for antifibrotic techniques. However the welfare implications, and thus ethical issues, in using primates are more concerning than with rodents or rabbits and efforts to refine, reduce and replace living animals in such model systems are crucially important. One problem is that the animal models normally involve healthy eyes, not ones with glaucoma. In veterinary ophthalmology we see large numbers of dogs with glaucoma, many of which have filtration implants placed. Potentially these could be a valuable animal model where benefits of antifibrotic treatment could benefit the animals involved and the research seeking to optimise such treatments.

Comparative efficacy of topical oclacitinib 0.1% and tacrolimus 0.01% in canine keratoconjunctivitis sicca

OBJECTIVE

To assess the efficacy of 0.1% oclacitinib as a single agent, and in combination with tacrolimus 0.01%, for the control of ophthalmic signs of keratoconjunctivitis sicca (KCS) in dogs.

ANIMALS STUDIED

Thirty-two dogs (57 eyes) diagnosed with idiopathic KCS were included. Inclusion criteria were Schirmer Tear Test 1 (STT-1) values <15 mm/min and concurrent clinical signs such as ocular hyperemia and discharge.

PROCEDURES

The animals were submitted to a randomized, open-label, 5-week study and divided into 3 treatment groups treated with the following ophthalmic solutions: (a) 0.1% oclacitinib, (b) 0.1% oclacitinib +0.01% tacrolimus, and (c) 0.01% tacrolimus. Eye drops were instilled twice daily (12-hour intervals). At each follow-up examination, STT-1, clinical signs, and potential drug side effects were assessed.

RESULTS

Oclacitinib did not significantly improve STT-1 values or clinical scores. Tacrolimus alone and in combination with oclacitinib increased mean STT-1 values by 11.84 ± 5.2 and 12.46 ± 5.3 mm/min, respectively (P = 0.0001). Clinical scores of ocular discharge and hyperemia also improved significantly in both groups receiving treatment with tacrolimus (P < 0.05). However, addition of oclacitinib to tacrolimus provided no additional improvement over tacrolimus alone.

CONCLUSIONS

Topical 0.1% oclacitinib twice daily is not effective in controlling the ocular signs of KCS in dogs. 0.01% tacrolimus increased STT-1 values significantly and could potentially be used as a treatment for mild-to-moderate cases of KCS. Synergism between drugs did not occur, and therefore the use of oclacitinib is not justified in cases of canine KCS.

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

INTRODUCTION

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

[Ocular involvement in atopic dermatitis : Clinical aspects and therapy]

Patients with atopic dermatitis frequently complain of ocular symptoms. The general dermatitis can directly affect the periocular skin and patients often present with chronic atopic blepharokeratoconjunctivitis. Early diagnosis of the characteristic ophthalmological alterations, such as blepharitis, allergic conjunctivitis, keratoconjunctivitis sicca, conjunctival scarring with formation of symblepharon and lid malpositioning, filiform keratitis, corneal plaques, (persistent) epithelial defects, corneal ulcers and keratoconus as well as appropriate stage-adapted treatment, including lid hygiene with preservative-free lubricants, topical and sometimes systemic anti-inflammatory therapy and surgical treatment are important for patients to prevent long-term damage of the ocular surface leading to severe visual impairment.

Immunohistochemical evaluation of lymphocyte populations in the nictitans glands of normal dogs and dogs with keratoconjunctivitis sicca

Idiopathic canine keratoconjunctivitis sicca (iKCS) is a common condition of the canine eye involving a deficiency in aqueous tear production which is commonly held to have an immune-mediated, as most probably an autoimmune aetiopathogenesis. Yet to date no direct evaluation has been made of the inflammatory cell populations in the lacrimal tissue of dogs with iKCS. Here we sought to quantify T and B lymphocyte populations in the lacrimal tissue of the nictitans glands of dogs with iKCS those with neurological KCS (nKCS)and also in dogs with tear production within the recognized normal levels and no ocular surface signs of KCS. Nictitans glands were obtained from 10 healthy dogs with no signs or history consistent with KCS at post-mortem or after enucleation. Nictitans glands were also obtained at parotid duct transposition surgery from ten dogs with idiopathic KCS and three with neurogenic KCS. Histological sections form the lacrimal tissue were processed immunohistochemically with primary monoclonal antibodies recognizing the T lymphocyte CD3 antigen and the B lymphocyte CD79a antigen. Cell numbers were counted in 10 randomly sampled representative high-power fields in five sections. Statistical significance of differences in cell numbers was determined using analysis of variance with significance achieved at p=0.05.Nictitans glands from dogs with iKCS showed elevated numbers of T and B lymphocytes compared with those from dogs with normal tear production. The increase in the T cell population was highly statistically significant (p=0.0025) while the increase in B cells, while statistically significant was less pronouncedly so (p=0.049). T and B lymphocyte numbers were not significantly elevated in nictitans glands from dogs with neurogenic KCS compared with those in dogs with normal tear production. The elevation in the T cell population seen in dogs with idiopathic KCS strongly supports the widely held assumption that this disease is an immune-mediated and probably autoimmune. The lack of increase in T cell populations in dogs with nKCS strongly suggests that the changes in iKCS are causing the tear deficiency and not resulting from it.

Cyclosporine A delivery to the eye: A comprehensive review of academic and industrial efforts

Local ocular delivery of cyclosporine A (CsA) is the preferred method for CsA delivery as a treatment for ocular inflammatory diseases such as uveitis, corneal healing, vernal keratoconjunctivitis and dry eye disease. However, due to the large molecular weight and hydrophobic nature of CsA and the natural protective mechanisms of the eye, achieving therapeutic levels of CsA in ocular tissues can be difficult. This review gives a comprehensive overview of the current products available to clinicians as well as emerging drug delivery solutions that have been developed at both the academic and industry levels.

Stability of an ophthalmic micellar formulation of cyclosporine A in unopened multidose eyedroppers and in simulated use conditions

Cyclosporine A eye drops are used at concentrations ranging from 0.5 to 20mg/mL to treat a variety of ophthalmic diseases. Cyclosporine A formulations at high concentrations are difficult to manufacture because of cyclosporine's lipophilicity, and generally require an oil based vector. In this study, we investigated the physicochemical and microbiological stability of two high concentrations (10mg/mL and 20mg/mL) of an ophthalmic cyclosporine A micellar solution in a low density polyethylene multidose eyedropper, at two conservation conditions (5°C and 25°C), before and with simulated use. Analyses used were the following: visual inspection, cyclosporine quantification by a stability-indicating liquid chromatography method, osmolality and pH measurements and turbidity. A complementary analysis by dynamic light scattering was implemented to evaluate potential particle formation or micelle size change. In the in-use study, cyclosporine quantification was also performed on the drops emitted from the multidose eyedroppers. Our results show that the cyclosporine micellar formulation retains good physicochemical and microbiological stability, as all parameters stayed within acceptable range limits, however a higher variability in cyclosporine concentrations was observed for 20mg/mL units stored at 25°C. The in-use study showed that cyclosporine concentrations in the emitted drops were also within acceptable range limits. The micellar formulation presented in this study can therefore be stored at 5°C or at ≤25°C for up to 6months.

A comparative review of Haute Autorité de Santé and National Institute for Health and Care Excellence health technology assessments of Ikervis® to treat severe keratitis in adult patients with dry eye disease which has not improved despite treatment with tear substitutes

Background: In 2015, Ikervis® became the only EMA-approved cyclosporine A (CsA) eye-drop for the treatment of severe keratitis in adult patients with dry eye disease, which has not improved despite treatment with tear substitutes. Since the 1980s, CsA has been used empirically for ocular conditions in veterinary medicine then in humans. However, its extremely low aqueous solubility led to its administration in vegetable oils, which is characterized by low ocular availability, poor intraocular penetration, poor tolerability and short shelf-life. Concentrations from 0.05% to 2% are compounded on an industrial scale and reimbursed throughout Europe. In France, Ikervis® has been granted an ASMR score of 5 by HAS, whereas in UK NICE endorsed its use. Objective: To review the dry eye disease environment, its challenges and available treatment options, and compare the NICE and HAS assessments to question HAS' decision to maintain full reimbursement of compounded CsA formulations in the absence of evidence, while reimbursing the EMA-approved drug at 15%.

METHOD

extensive search on PubMED. Results: Comparator selection, composite score assessment and use of CE model are key differentiators. Conclusion: In topical formulations, improvements to the vehicle are key innovations that can bring significant benefits. After the USA, a Compounding Act is needed in Europe.

Lacrimal Gland Inflammation Deregulates Extracellular Matrix Remodeling and Alters Molecular Signature of Epithelial Stem/Progenitor Cells

PURPOSE

The adult lacrimal gland (LG) is highly regenerative and is able to repair itself even after substantial damage; however, this ability to regenerate is lost with the development of dry eye conditions in chronically inflamed LGs.This study compares changes in the cell adhesion and cell matrix molecules and stem cell transcription factors in the LGs of healthy mice and of two mouse models of Sjögren's syndrome: nonobese diabetic (NOD) and MRL-lpr/lpr (MRL/lpr) mice during the early stage of inflammation.

METHODS

The LGs from 12- to 13-week-old female MRL/lpr and male NOD mice along with their respective control strains were harvested and divided into three pieces and processed for quantitative (q) RT-PCR and qRT-PCR Arrays, histology, immunohistochemistry, and Western blotting.

RESULTS

The extracellular matrix (ECM) and adhesion molecules RT2-PCR array combined with protein expression data revealed changes in the expression of integrins, matrix metalloproteinases, and other molecules, which are associated largely with invasion, attachment, and expansion of the lymphocytic cells, whereas changes in the stem cell transcription factors revealed substantial decrease in expression of transcription factors associated with epithelial stem/progenitor cell lineage.

CONCLUSIONS

We concluded that the expression of several important ECM components is significantly deregulated in the LG of two murine models of Sjögren's syndrome, suggesting an alteration of the epithelial stem/progenitor cell niche. This may result in profound effects on localization, activation, proliferation, and differentiation of the LG stem/progenitor cells and, therefore, LG regeneration.

Safety and efficacy of cyclosporine in the treatment of chronic dry eye

Dry-eye syndrome (DES) is a multifactorial disease affecting millions of individuals worldwide. Various factors, including age, hormonal status, genetics, sex, immune status, innervation status, nutrition, pathogens, and environmental stress, can alter the cellular and molecular structure or function of components of the ocular surface system. The resulting imbalance increases susceptibility to desiccation and epithelial damage, leading to a vicious circle in which inflammation amplifies and sustains further damage by chronic deregulation of the system. Lubricating agents and steroids have been used as treatment options. However, as the causes of the disease become better elucidated, the more chemically complex cyclosporine A has become an increasingly useful treatment option and in the United States is currently the only Food and Drug Administration (FDA)-approved prescription drug for the treatment of dry eye. The safety and efficacy of cyclosporine have been shown in numerous studies.

Developing an in situ nanosuspension: a novel approach towards the efficient administration of poorly soluble drugs at the anterior eye

With about 50-60 million cases in the US alone, dry eye disease represents a severe health care problem. Cyclosporin A (CsA) would be a potent candidate for a causal therapy. However, CsA is not sufficiently water soluble to be administrated via simple eye drops. We developed an in situ nanosuspension (INS) as a novel approach towards the administration of CsA to the cornea. It precipitates upon contact with the tear fluid and creates CsA nanoparticles that enter the cornea and release the drug by dissolution. We selected two liquid poly(ethylene glycols) (PEG) that dissolve CsA and create nanoparticles by precipitation of CsA upon water contact. Aqueous solutions of PEG and Solutol, a non-ionic surfactant, were well tolerated by primary human epithelial cells in vitro. To determine the critical water content needed for a precipitation, the solubility of CsA was investigated in quaternary systems of drug, solvent, surfactant and water. The best INS formulation showed a particle size of 505 ± 5 nm, a polydispersity index (PdI) of 0.23 ± 0.03 and a neutral zeta potential of -0.07 ± 0.05 mV. After single administration to porcine eyes in vitro, 3165 ± 597 ng(CsA)/g(cornea) were detected in corneal tissue, while the levels of Restasis a commercial formulation were, with 545 ± 137 ng(CsA)/g(cornea), significantly lower (P<0.01). These results demonstrate that an INS is a promising, novel approach towards the causal treatment of inflammatory diseases at the anterior eye.

Ocular delivery of cyclosporine A based on glyceryl monooleate/poloxamer 407 liquid crystalline nanoparticles: preparation, characterization, in vitro corneal penetration and ocular irritation

The purpose of this study was to develop an ophthalmic drug delivery system for cyclosporine A (CsA) based on glyceryl monooleate (GMO)/poloxamer 407 liquid crystalline nanoparticles with reduced ocular irritancy and improved corneal penetration. CsA-loaded liquid crystalline nanoparticles were prepared via fragmentation of a bulk GMO/poloxamer 407 cubic phase gel by high-pressure homogenization and characterized. Corneal permeation and retention was evaluated using modified Franz diffusing cells. Intra-corneal transportation was investigated with fluorescein isothiocyanate (FITC)-labeled liquid crystalline nanoparticles. Ocular irritation was then evaluated using the Draize method. The mean particle size of liquid crystalline nanoparticles was 193.5 nm and the entrapment efficiency was 95.11 ± 0.67%. A bicontinuous cubic phase of cubic P-type was determined using cryo-transmission electron microscopy (cryo-TEM) observation and small angle X-ray diffraction (SAXD) analysis. A 1.52-fold increase in J(s) and a 2.2-fold increase in corneal retention was achieved by liquid crystalline nanoparticles compared with oil solution. In vitro corneal permeation investigated with FITC-labeled liquid crystalline nanoparticles revealed that CsA penetrated across the cornea under the transportation of liquid crystalline nanoparticles. Liquid crystalline nanoparticles exhibited excellent ocular tolerance in the ocular irritation test. This low-irritant vehicle based on liquid crystalline nanoparticles might be a promising system for effective ocular CsA delivery.

An overview on dry eye treatment: approaches for cyclosporin a delivery

Dry eye syndrome (DES, Keratoconjunctivitis sicca) is a common disorder of the tear film caused by decreased tear production or increased evaporation. Changes in tear composition also promote inflammation on the ocular surface by various mechanisms. Artificial tear drops, tear retention treatment, stimulation of tear secretion, or anti-inflammatory drugs may be used for dry eye treatment according to the severity of the disease. For untreated patients, the risk of ocular infection increases at considerable level and clinical course of the disease may proceed up to infection, corneal ulcer, and blindness. Artificial tears and/or punctual occlusions are used for tear replacement or preservation. New treatment approaches are designed to modify the underlying disease process. For the treatment of severe dry eye disease, cyclosporin A (CsA), the first one of the new generation immunomodulatory drugs, which has an anti-inflammatory effect, is frequently used. CsA has immunosuppressive effects following systemic application. Following local administration of CsA, it is expected to obtain effective drug concentration at the target area and to avoid the various side effects associated with systemic delivery. Microspheres, implants, and liposomes have been developed for administration of CsA subconjunctivally in order to enhance its efficiency.

Clinical review: topical ophthalmic use of cyclosporin A

Cyclosporine A (CsA) is an immunomodulatory agent that primarily inhibits the proliferation and action of T cells. Systemic CsA has been used successfully in solid organ transplantation and noninfectious uveitis. Topical CsA with various formulations has been used in the field of ocular surface diseases since early 1980s. An ophthalmic emulsion 0.05% (Restasis, Allergan, Irvine, CA), was approved by the United States Food and Drug Administration in 2003 to treat dry eye syndrome. This article aims to evaluate the peer-reviewed published scientific literature and to define well-established uses of CsA eyedrops in the field of ocular surface diseases.

Lack of effects on lymphocyte function from chronic topical ocular cyclosporine medication: a prospective study

AIM

Topical cyclosporine has been widely used in the treatment of canine keratoconjunctivitis sicca without apparent documented clinical side effects. Thus the finding of reduced lymphocyte proliferation in animals treated with the drug at a concentration of 2% was both surprising and concerning. This study aimed to repeat the previous study and to compare the systemic effects of 2% cyclosporine in corn oil and 0.2% topical cyclosporine ointment (Optimmune, Intervet-Schering Plough, Welwyn, UK).

METHODS

Twenty dogs treated with Optimmune or with topical 2% cyclosporine in corn oil where previous treatment with Optimmune had failed were included in this study. Blood samples were taken at the time of first evaluation and at 1, 3 and 6 months of treatment to provide a biochemical and hematological health evaluation of the dogs and at each examination to measure circulating levels of cyclosporine and to obtain a lymphocyte population with which to determine a mitogen stimulation index (MSI) on treatment with phytohaemagglutinin-P (PHA) and conconavlin A (con-A). Levels of circulating cyclosporine were measured with an enzyme-multiplied immunoassay method and also the more sensitive quantification technique of mass spectroscopy (MS).

RESULTS

No blood samples contained over 15 ng/ml cyclosporine, the lower limit of detection using the radioimmunoassay or the enzyme-multiplied immunoassay technique. Positive control samples taken from dogs treated with oral cyclosporine for anal furunculosis showed measurable levels in blood, demonstrating that the technique worked. Mean MSI values at 0, 1, 3 and 6 months of treatment were 10.2, 11.4, 11.6, and 10.5 for dogs treated with 0.2% cyclosporine and 10.4, 11.9, 11.7, and 12.9 for dogs treated with 2% cyclosporine. Mitogen stimulation index values were not statistically different between the first examination and any subsequent examination time-point.

CONCLUSIONS

The findings of the study contradict those of the previous studies. No change in lymphocyte stimulation index was noted, neither were significant blood levels of cyclosporine documented after topical administration of either 0.2% or 2% cyclosporine. This study shows that topical cyclosporine is safe to use in the canine eye in line with the drug's safety record in this therapeutic regime over the past 20 years since its first use.

Immunopathogenesis of keratoconjunctivitis sicca in the dog

Keratoconjunctivitis sicca (KCS), more commonly known as dry eye, is an inflammatory condition of the ocular surface caused by a pathologic reduction in the aqueous component of the tear film. It is seen commonly in the dog and defined as a Schirmer tear test with a reading of less than 10 mm in one minute. While KCS may be caused by neurological disease or drug toxicity, most cases are immune-mediated. Whereas the immunological basis of autoimmune KCS has been extensively investigated in humans and experimental rodent models, little research has been undertaken in the dog. It is hoped that this review spurs further research into the etiopathogenic factors in canine KCS.

Uses and safety profile of ciclosporin in ophthalmology

Ciclosporin is a calcineurin inhibitor that acts by primarily inhibiting the action of T cells. Clinical trials in the early 1980s demonstrated that systemic ciclosporin was a promising steroid-sparing agent and was also effective in patients who are refractory to treatment with corticosteroids. However, recent years have witnessed the emergence of safer immunosuppressive agents due to the poor side-effect profile of systemic ciclosporin. Topical ciclosporin, however, has a much improved safety profile and is still used to treat a variety of ocular surface disorders including dry eye syndrome, vernal and atopic keratoconjunctivitis, severe blepharitis and high-risk corneal graft patients. This article reviews the uses and safety profile of systemic and topical ciclosporin in ophthalmology, as well as discussing alternative therapeutic agents available.

Cyclosporin as an adjunct to glaucoma filtration surgery

PURPOSE

Current adjunctive therapies to glaucoma surgery have unreliable effects, are toxic, and have numerous late complications associated with their use. This study examined whether topical cyclosporin (CsA) prolongs bleb survival after glaucoma filtration surgery.

METHODS

Anesthetized white New Zealand rabbits underwent glaucoma filtration surgery with a drainage tube. Cyclosporin (2%), applied intraoperatively or as topical treatment following glaucoma filtration surgery, was compared with intraoperative mitomycin C (MMC) and an untreated control group.

RESULTS

The bleb remained elevated for 15.1 +/- 3.2 days in the untreated control group, 12.2 +/- 2.1 days after intraoperative cyclosporin, and 27.5 +/- 1.7 days after intraoperative mitomycin C (P < 0.001). When topical treatment with cyclosporin followed intraoperative mitomycin C, bleb survival significantly decreased to 19.2 +/- 4.6 days (P = 0.003). Intraocular pressure (IOP) remained significantly reduced in the mitomycin C-treated group longer than in either the control or cyclosporine-treated groups.

CONCLUSIONS

In comparison with mitomycin C, neither intraoperative nor postoperative treatment with cyclosporin was associated with a decrease in intraocular pressure or prolonged bleb survival. Contrary to the initial hypothesis, topical treatment with cyclosporin actually mitigated the beneficial effects of mitomycin C on bleb survival. Clinical implications of these findings for patients with functioning blebs deserve further study.

Topical ciclosporin in the treatment of ocular surface disorders

Mounting evidence suggests that inflammation is the key factor in the pathogenesis of various ocular surface diseases, with a complex interplay of genetic, environmental, and psychosocial factors. Management of these conditions is often challenging. Topical corticosteroids, with their associated side effects, are the mainstay of current treatments for patients with vision threatening disease. Ciclosporin A is an immunomodulator that specifically inhibits T lymphocyte proliferation. Recently, a topical ciclosporin preparation was approved by the US Food and Drug Administration and became available for use in ophthalmology. Given the increasing use of ciclosporin eye drops, the goal of this article is to provide the reader with an overview of the well established uses of ciclosporin and to help refine the questions that should be addressed by future investigations.

Removal of giant vernal papillae by CO2 laser

BACKGROUND

We report our experience in removing giant papillae in cases with severe vernal keratoconjunctivitis using CO2 laser.

METHODS

Five cases with conjunctival giant papillae due to severe vernal keratoconjunctivitis were treated with CO2 laser. All cases were resistant to conventional treatment. In 4 eyes, there was also an associated corneal shield ulcer.

RESULTS

In all 5 cases the procedure was uneventful. Retreatment was performed in only 2 cases because of recurrence of the papillae. No intra- or postoperative complications were observed.

INTERPRETATION

CO2 laser seems to be a safe method for removing conjunctival giant papillae in cases with severe vernal keratoconjunctivitis. It is also a repeatable method that enables a rapid conjunctival and corneal recovery.

Topical FK506 as immunoprophylaxis after allogeneic penetrating normal-risk keratoplasty: a randomized clinical pilot study

The purpose of this study was to evaluate for the first time the efficacy and safety of topical FK506 in patients undergoing penetrating normal-risk keratoplasty in a prospectively randomized clinical trial. Twenty patients were treated with FK506 0.06% three times per day for 6 months postoperatively. An additional 20 patients received five drops of prednisolone acetate 1% tapered within 6 months. All patients received 1 mg/kg bodyweight/day of systemic fluocortolon tapered within 3 weeks postoperatively. Clear graft survival, ratio of immune reactions and side effects were the main outcome measures. One year postoperatively all patients of the FK 506 group were free from immune reactions, in contrast to 84% in the steroid group (Kaplan-Meier values; P = 0.9 in the log rank test). None of the patients developed irreversible graft failure so far. In eight patients of the FK506 group premature withdrawal of the drug was deemed appropriate because of local side effects. FK506 might turn out to become an effective immunoprophylaxis in subjects undergoing penetrating normal-risk keratoplasty. Local discomfort should be further reduced.

Topical Cyclosporine A Inhibits Subepithelial Immune Infiltrates but Also Promotes Viral Shedding in Experimental Adenovirus Models

PURPOSE

To determine the effects of topical cyclosporine A (CsA), an immunomodulating T-cell inhibitor, on the formation of subepithelial immune corneal infiltrates (SEIs) and acute adenovirus replication in the NZW Rabbit Ad5 SEI and Ad5 replication models.

METHODS

In the Ad5 SEI model, eyes were treated topically with either 2% CsA in corn oil, 0.5% CsA in artificial tears, or their respective control vehicles 4 times daily for 14 days and then twice daily for 4 days. SEIs were graded on day 23 by masked slit-lamp examination. Using the same treatment protocol in the Ad5 replication model, rabbit eyes were cultured on days 0, 1, 3, 4, 5, 7, 9, 11, 14, 16, 18, and 21 postinoculation, and their tear film viral titers were determined on A549 cells.

RESULTS

The formation of SEIs was significantly reduced following treatment with either 2.0% or 0.5% CsA. However, 2% and 0.5% CsA significantly increased viral titers on several days, prolonged the duration of Ad5 shedding, and increased the number of Ad5-positive cultures per total during the late phase of infection (days 7-21) compared with their respective controls. The 0.5% CsA was equipotent to 2% CsA for most outcome parameters tested.

CONCLUSIONS

A role for topical CsA in the treatment of adenovirus ocular infections remains to be defined in large, randomized controlled clinical trials. During acute infection, reducing SEI formation is highly desirable, but enhancing viral replication may inadvertently serve to promote local epidemics. Future trials should address the important issues of optimized formulation and dose regimen and the possibility of prolonging virus shedding.

Cyclosporine A delivery to the eye: a pharmaceutical challenge

Systemic administration of cyclosporine A (CsA) is commonly used in the treatment of local ophthalmic conditions involving cytokines, such as corneal graft rejection, autoimmune uveitis and dry eye syndrome. Local administration is expected to avoid the various side effects associated with systemic delivery. However, the currently available systems using oils to deliver CsA topically are poorly tolerated and provide a low bioavailability. These difficulties may be overcome through formulations aimed at improving CsA water solubility (e.g. cyclodextrins), or those designed to facilitate tissue drug penetration using penetration enhancers. The use of colloidal carriers (micelles, emulsions, liposomes and nanoparticles) as well as the approach using hydrosoluble prodrugs of CsA have shown promising results. Solid devices such as shields and particles of collagen have been investigated to enhance retention time on the eye surface. Some of these topical formulations have shown efficacy in the treatment of extraocular diseases but were inefficient at reaching intraocular targets. Microspheres, implants and liposomes have been developed to be directly administered subconjunctivally or intravitreally in order to enhance CsA concentration in the vitreous. Although progress has been made, there is still room for improvement in CsA ocular application, as none of these formulations is ideal.

Topical cyclosporine in the management of shield ulcers

PURPOSE

To report our experience with 0.05%-2% topical cyclosporine in the treatment of 4 cases of severe, corticosteroid-resistant, vernal keratoconjunctivitis with shield ulcers.

METHODS

Four patients with shield ulcers not responding to medical treatment with topical steroids, antihistamines, and mast-cell stabilizers were treated with 0.05%-2% topical cyclosporine. The frequency of application was 4 times daily in all cases, and the concentration was adjusted according to the clinical status starting with 2%.

RESULTS

Healing of ulcers with no epithelial defect occurred in 10 days with the 2% concentration in all cases. The patients experienced no side effects except for a burning sensation during administration. Recurrences occurred when the concentration was decreased to 0.05% in 3 cases. The recurrences were effectively treated with 1% concentration in all cases, and patients were stable with this concentration for at least 6 months.

CONCLUSIONS

Topical cyclosporine is an effective treatment alternative in the management of shield ulcers in patients with vernal keratoconjunctivitis. The 1% concentration seems to be the minimal effective concentration in such cases in our experience, but further controlled studies are needed to support our findings.

Xerostomia, xerophthalmia, and plasmacytic infiltrates of the salivary glands (Sjögren's-like syndrome) in a cat

A 2.5-year-old domestic shorthair cat was evaluated because of dysphagia and weight loss of 4 weeks' duration. MIld blepharospasm and conjunctival hyperemia were evident in both eyes, oral mucous membranes were tacky on palpation, and salivary glands were enlarged. Results of a Schirmer tear test were 0 mm/min for both eyes. Administration of atropine did not cause salivation or caused secretion fo thick rope-like saliva. Examination of biopsy specimens of salivary glands revealed a plasmacytic infiltrate. Sjögren's syndrome (SS) was diagnosed. Oral administration of prednisone was instituted but was discontinued after a minimal positive response was evident 6 weeks after initiation of treatment. Palliative treatment with a 6% solution of pilocarpine 4 to 5 times/d, cyclosporine, hylan A, and neomycin-polymyxin-bacitracin ophthalmic ointment resulted in clinical improvement in the cat. Although reported rarely in animals, SS may be more common than currently is recognized. Most treatment regimens for SS are aimed at alleviating clinical signs.

A new look at dry eye disease and its treatment

This review examines the impact of moderate to severe dry eye disease on daily life and medical-resource utilization. The results suggest that current treatment paradigms can lead to unacceptable costs in both quality of life and progressive use of healthcare resources. Evidence linking this disease to T-cell-mediated inflammatory processes lays the foundation for understanding the clinical benefits of topical cyclosporine, an immunomodulatory and anti-inflammatory agent.