Alleviation of Allergic Rhinoconjunctivitis Symptoms in Participants Treated with a 0.005% Tacrolimus Eye-Drop Solution

Purpose

This randomized, placebo-controlled, crossover, double-blind trial aimed to evaluate the efficacy and safety of Tacrosolv, a novel 0.005% tacrolimus eye-drop solution, in adults with grass pollen-induced allergic conjunctivitis.

Methods

A total of 64 adult participants were randomized to receive 2.5 µg or 5 µg tacrolimus/eye/day or placebo treatment for 8 days, with grass pollen exposure on day 1 and day 8. After a 2-week washout period, placebo participants crossed over to Tacrosolv treatment and vice versa, with repeated treatment and exposure. During exposure, participants recorded ocular, nasal, and respiratory allergy symptoms every 15 minutes. The primary endpoint was the mean total ocular symptom score (TOSS) on day 8. Objective ocular safety parameters were assessed before, during, and after exposure. Adverse events were recorded throughout the study.

Results

On day 8, high-dose Tacrosolv reduced the TOSS compared to placebo towards the end of exposure (p<0.05 at time points 3 hours, 45 minutes and 4 hours). A 26% reduction in baseline adjusted TOSS from day 1 to day 8 was observed in participants treated with high-dose Tacrosolv, whereas placebo-treated participants showed no difference in TOSS between day 1 and day 8. Nasal symptoms were reduced on both day 1 and day 8 in participants treated with high-dose Tacrosolv (p<0.05). No safety concerns were raised. All adverse events were resolved within the study period.

Conclusion

High-dose Tacrosolv is safe and effective for alleviating symptoms of allergic rhinoconjunctivitis.

Trial Registration

NCT04532710; EudraCT No. 2019-002847-62.

Retinal transplant immunology and advancements

Several gaps and barriers remain for transplanting stem cells into the eye to treat ocular disease, especially diseases of the retina. While the eye has historically been considered immune privileged, recent thinking has identified the immune system as both a barrier and an opportunity for eye stem cell transplantation. Recent approaches leveraging scaffolds or cloaking have been considered in other tissues beyond immune suppression. This perspective paper outlines approaches for transplantation and proposes opportunities to overcome barriers of the immune system in stem cell transplantation in the eye.

Chloropicrin induced ocular injury: Biomarkers, potential mechanisms, and treatments

Ocular tissue, especially the cornea, is overly sensitive to chemical exposures. The availability and adoption of chemical threat agent chloropicrin (CP) is growing in the United States as a pesticide and fumigant; thereby increasing the risk of its use in warfare, terrorist attacks and non-intentional exposure. Exposure to CP results in immediate ocular, respiratory, and dermal injury; however, we lack knowledge on its mechanism of toxicity as well as of its breakdown products like chlorine and phosgene, and effective therapies are elusive. Herein, we have reviewed the recent findings on exposure route, toxicity and likely mechanisms of CP induced ocular toxicity based on other vesicating chemical warfare agents that cause ocular injury. We have focused on the implication of their toxicity and mechanistic outcomes in the ocular tissue, especially the cornea, which could be useful in the development of broad-spectrum effective therapeutic options. We have discussed on the potential countermeasures, overall hallmarks and challenges involved in studying ocular injuries from chemical threat agent exposures. Finally, we reviewed useful available technologies and methods that can assist in the identification of effective medical countermeasures for chemical threat agents related ocular injuries.

Long-Term Clinical Outcome of Tacrolimus Skin Ointment (0.03%) for the Treatment of Vernal Keratoconjunctivitis: A Quasi-Experimental Study

Background Vernal keratoconjunctivitis (VKC) is an allergic conjunctival inflammation with severe ocular complications if left untreated. The current management regimen is plagued with adverse effects, long-term problems, and clinical relapses. Tacrolimus offers an alternative treatment option, and long-term studies are needed to determine its efficacy. Methods A two-year follow-up based study was conducted on moderate to severe VKC patients, who were prescribed tacrolimus skin ointment. The 5-5-5 exacerbation scale was used for the monitoring and grading severity of the disease. Analysis of variance (ANOVA) and intergroup comparisons were conducted on exacerbation scale scores among follow-ups. Results A significant reduction was observed in the total score of severity from baseline (203.17±102.05) to three months' follow-up (69.94±70.54), and it kept reducing for 18 months post therapy. Similar results with statistically significant reduction were observed for all grades of the scale. The relapse rate was 5.71% within a month after therapy cessation, and none of the other patients showed relapse afterward. No significant ocular and systemic complications were observed during the study. Conclusion Tacrolimus is effective in the long-term management of VKC without the complications of conventional steroid-based therapy.

Mechanoresponsive Drug Loading System with Tunable Host-Guest Interactions for Ocular Disease Treatment

Conventional administration of eye drops often requires high dosages and/or repetitive treatments to achieve therapeutic efficacy. This is inefficient and may result in side effects or even toxicity. Although many delivery systems of ophthalmic drugs have been reported, most of them work in a fixed format in which both the type and dose of the loaded drugs cannot be changed upon demand. To overcome this limitation, a hybrid double network hydrogel system composed of methacryloyl gelatin, pluronic F127 diacrylate, and β-cyclodextrin-modified oxidized dextran was developed. The hydrogels presented good mechanical strength and biocompatibility. In vitro assessments demonstrated that the hydrogels loaded with commonly used ophthalmic drugs could sustain the drug release for more than 21 days. This hydrogel system exhibited features of mechanoresponsive drug loading, and the capacity of drug loading could be significantly enhanced by macroscopically mechanical compression. Further in vivo evaluation of the drug delivery capacity showed that a dexamethasone-loaded hydrogel as a fornix insert effectively suppressed upregulation of proangiogenic factors and suture-induced corneal neovascularization in rats. This novel hydrogel system represents a promising drug delivery platform, which could potentially improve the treatments of ocular surface and other diseases.

The Effect of Anti-Inflammatory Topical Ophthalmic Treatments on In Vitro Corneal Epithelial Cells

Purpose

To compare the effect of three commonly prescribed anti-inflammatory eye drops on corneal epithelial cells in vitro.

Methods

Three different lines of human corneal epithelial cells were tested: primary cells cultured from donor tissue, commercially available primary cells, and immortalized cells. Cells were seeded on 96-well plates and treated with the following eye drops: cyclosporine 0.05%, lifitegrast 5%, and tacrolimus 0.03% or 0.1%. Exposure times tested were 30 seconds, 1 minute, 2 minutes, 1 hour, 2 hours, 4 hours, and 24 hours. Brightfield images and viability assays were analyzed 48 to 72 hours after the initiation of treatments. At least five replicates were tested per drug and time exposure.

Results

Commercially obtained primary cells showed reduced viability following 1 hour with tacrolimus 0.1% (8%; P = 0.043%) and 4 hours with tacrolimus 0.03% (17%; P = 0.042%). Lifitegrast exposure reduced primary cell viability after 4 hours (10%; P = 0.042). Cell viability in primary cells was not deleteriously affected following exposure to cyclosporine for up to 4 hours. A similar trend was observed in both primary cells cultured from donor tissue and immortalized human corneal epithelial cells, demonstrating greater decreases in cell viability in tacrolimus compared to lifitegrast and cyclosporine. Light microscopy imaging for analysis of cell morphology and confluence supported the results.

Conclusions

Tacrolimus showed the highest impact on corneal epithelium survival in vitro, and cyclosporine proved the most protective.

Translational Relevance

Comparing anti-inflammatory eye drops on corneal epithelial cells in vitro may inform eye drop selection and development for clinical purposes.

Preparation of a novel tacrolimus ion sensitive ocular in situ gel and in vivo evaluation of curative effect of immune conjunctivitis

BACKGROUND

The aim of this study was to formulate a novel TAC preparation into an in situ gel for ocular drug delivery, in order to prolong the residence time on mucosal surfaces and increase patient compliance.

METHODS

The optimal formulation was characterized by surface morphology, gelling capacity, viscosity, stability and in vitro release. In vivo studies were also conducted to evaluate the precorneal retention and pharmacodynamic results.

RESULTS

In this study, the TAC in situ gel can be prepared by a simple solvent stirring method, and the optimized formulation exhibited good stability within 3 months. During storage, the initial viscosity of the formula had little change. The results of viscosity measurement showed that TAC in situ gel was typical of pseudo plastic systems and exhibited a marked increase in viscosity stimulated with STF. In vitro and in vivo studies illustrated that TAC in situ gel administration facilitated the retention and sustained release of TAC.

CONCLUSIONS

TAC combined with in situ gelling agents demonstrates an efficient topical drug delivery platform.

Incremental Concentrations of Tacrolimus Eye Drops as a Strategy for the Management of Severe Vernal Keratoconjunctivitis

Purpose: To assess the effect of different concentrations of tacrolimus eye suspension on the epithelium and stromal keratocytes of human corneas and investigate whether it can be safely used for severe cases of vernal keratoconjunctivitis (VKC).

Methods: Tacrolimus eye suspension was prepared in a range of concentrations of 0.005%, 0.01%, 0.05%, 0.1%, and 0.2%. Molecular analysis was performed ex vivo on human corneas (n = 18), obtained from the eye bank. Transparency and thickness of each cornea were measured while live/dead staining was performed using a triple labeling assay. An incremental concentration approach was then tested on three severe cases of VKC.

Results: All tested tacrolimus concentrations showed no significant changes in corneal thickness or transparency. In corneas treated with 0.1%, rare scattered dead cells were observed, while the folds of corneal surfaces were mostly viable, unlike concentrations higher than 0.1% and lower than 0.05%. Stromal cell densities were highest in the 0.1% tacrolimus treatment condition. Incremental concentrations of tacrolimus suspension were shown to significantly improve VKC cases, where the concentration used for each case depended on the severity of the case.

Conclusions: Topical administration of tacrolimus was not toxic to human corneal cells at all tested concentrations, and the 0.1% concentration has shown the best viability of the corneal tissue. Tacrolimus eye suspension was shown to be safe and effective for use in severe VKC and is proposed as a topical ocular immunosuppressant drug enabling clinicians to incrementally increase the drug concentration according to the clinical severity of the disease to achieve the optimal therapeutic response.

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.

Combination of 0.05% Azelastine and 0.1% Tacrolimus Eye Drops in Children With Vernal Keratoconjunctivitis: A Prospective Study

Aims: To compare the efficacy of the combination of 0. 05% azelastine and 0.1% tacrolimus eye drops with 0.1% tacrolimus monotherapy in pediatric patients with vernal keratoconjunctivitis (VKC). Methods: Prospective study. Seventy-six patients with VKC were randomized 1:1 into monotherapy group with 0.1% tacrolimus or combination therapy group with 0.1% tacrolimus and 0.05% azelastine. The Ocular Surface Disease Index (OSDI) scores and the signs of conjunctival hyperemia, corneal involvement, and palpebral conjunctiva papillae were assessed at baseline and at 1, 2, and 6 weeks after treatment. Results: Two groups were comparable in age, sex, duration of VKC, OSDI, and clinical signs of VKC at baseline. Significant improvements in OSDI score and clinical signs were observed in both groups at all follow-up visits (all p < 0.001), compared with baseline. The combination therapy group showed a larger decrease in OSDI score from baseline (10.30 ± 0.9) compared with monotherapy group (7.30 ± 0.7, p =0.0085) at 1 week. Greater improvements in conjunctival hyperemia and conjunctival papillae were identified in the combination therapy group, compared with in the monotherapy group, at all follow-up visits (all p < 0.05). The corneal involvement scores in the combination group is significantly lower than the monotherapy group at 2 weeks after the treatment (p = 0.0488). No severe adverse effect was found in either group during the study. Conclusions: Compared with a monotherapy of 0.1% tacrolimus, the combination of 0.05% azelastine and 0.1% tacrolimus eye drops lead to faster and greater improvements in clinical signs and symptoms of vernal keratoconjunctivitis in pediatric patients.

Long-term results of topical 0.02% tacrolimus ointment for refractory ocular surface inflammation in pediatric patients

BACKGROUND

No studies have been reported on the efficacy and safety of long-term (≥12 months) use of topical tacrolimus for refractory ocular surface inflammation in pediatric patients.

METHODS

Medical records of pediatric patients who were prescribed topical 0.02% tacrolimus ointment for refractory ocular surface inflammation between January of 2010 and March of 2018 were reviewed retrospectively. Changes in ocular surface signs during slit-lamp examination, clinical symptoms and concurrent steroid use were graded with a scoring system. The presence of side effects was also assessed. The changes in disease severity and patient symptoms were compared between baseline and after the treatment.

RESULTS

Among 72 patients (55% males, mean age 10.8 ± 3.9 years, range 3 to 17 years), 25 patients (48% males, mean age 11.4 ± 3.9 years) fully recovered, resulting in discontinuance of the ointment treatment before 12 months. Six patients experienced intolerable burning sensation, which required treatment cessation. Cessation days of those who quit were 1,5,14,20,26, and 35 days. Seven patients were lost during follow-up. Thirty-four patients (56% males, mean age 11.2 ± 4.2 years, range 3 to 17 years) were treated with tacrolimus ointment for over 12 months (average 23.1 ± 19.1 months, range 12 to 98 months). During the follow-up period, all patients showed improved clinical signs and symptoms, and no adverse reaction was noted.

CONCLUSIONS

Long-term maintenance of topical tacrolimus 0.02% ointment is safe and effective in improving refractory ocular surface inflammation in pediatric patients.

Sequelae of microsporidial keratoconjunctivitis and its management

Purpose:

To characterize the sequelae of microsporidia keratoconjunctivitis (MKC) and outline its management.

Methods:

Retrospective analysis of microbiologically proven MKC returned with persistent disease between January 2015 and December 2019 was done. Demographics, clinical features, management, and outcome were analyzed.

Results:

Sixteen patients (21 eyes) of 332 treated for MKC returned with the persisting disease. The mean age of 11 males (68.7%), and 5 females was 35.1 ± 12.2 years. Three-quarter of them did not have a known predisposing risk factor and one-quarter of them were referred for chronic conjunctivitis. Past medications included topical antivirals (n = 8) and topical corticosteroid (n = 6). Three predominant presentations were persistent (>3 weeks) superficial punctate keratitis (SPKs, n = 7), sub-epithelial infiltrates (SEIs, n = 13), and uveitis (n = 2). The lesions recurred in eight eyes (SPK and SEI 4 each) after a disease-free interval of 60.4 ± 40.6 days; there were 13 episodes of recurrence. Topical low potent corticosteroids (loteprednol/fluorometholone), and tacrolimus ointment 0.03% were used in 17 (80.9%) and 8 (38%) eyes, respectively, for a mean duration of 44.8 ± 31.6 and 226.8 ± 180.5 days, respectively. At follow-up, 172.3 ± 183.6 days, visual recovery was statistically significant in persistent eyes (BCVA 0.07 ± 0.07 logMAR; P < 0.00001) but, not in recurrent eyes (BCVA 0.16 ± 0.08 logMAR; P = 0.07). Five of 21 eyes were left with residual significant scar.

Conclusion:

The sequelae of microsporidial keratoconjunctivitis are not uncommon. Topical 0.03% tacrolimus ointment appeared to be an effective corticosteroid-sparing agent for the treatment of SEIs and prevention of recurrence.

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.

Experience With 0.1% Tacrolimus Eye Drop for Noninfectious, Non-necrotizing Anterior Scleritis

OBJECTIVES

To report experience with 0.1% tacrolimus eye drops in the treatment of noninfectious, non-necrotizing anterior scleritis.

METHODS

This prospective, single-arm study included nine patients (4 men and 5 women; mean age=59.4 years, SD=10.5) with anterior scleritis. All patients were first treated with steroids for 1 month and then switched to tacrolimus eye drops alone. We defined baseline as the initiation of tacrolimus eye drops. Hyperemia and pain were scored before each treatment, at 1 and 2 weeks, and at 1 month after initiation of each treatment using 5 grades (0=none; 1+=mild; 2+=moderate; 3+=severe; 4+=extremely severe). Intraocular pressure (IOP) was also measured during treatment with each drug. Safety was assessed based on the severity and the incidence of adverse events.

RESULTS

The scores of hyperemia and pain had significantly decreased from baseline by 1 week after initiating tacrolimus eye drops (both P<0.05). No significant reduction was observed with steroid treatment throughout the 1-month period in both scores. Tacrolimus eye drops elicited statistically significant differences in mean IOP over the course of treatment (P=0.02). No additional medications were required to provide relief in any of the patients receiving tacrolimus treatment. No patient demonstrated infectious adverse events after initiation of tacrolimus treatment.

CONCLUSIONS

Topical tacrolimus may effectively and immediately reduce clinical signs and symptoms of noninfectious, non-necrotizing anterior scleritis in cases unresponsive to a course of topical steroid.

Development and Characterization of a Tacrolimus/Hydroxypropyl-β-Cyclodextrin Eye Drop

Uveitis is a vision inflammatory disorder with a high prevalence in developing countries. Currently, marketed treatments remain limited and reformulation is usually performed to obtain a tacrolimus eye drop as a therapeutic alternative in corticosteroid-refractory eye disease. The aim of this work was to develop a mucoadhesive, non-toxic and stable topical ophthalmic formulation that can be safely prepared in hospital pharmacy departments. Four different ophthalmic formulations were prepared based on the tacrolimus/hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complexes’ formation. Phase solubility diagrams, Nuclear Magnetic Resonance (NMR) and molecular modeling studies showed the formation of 1:1 and 1:2 tacrolimus/HPβCD inclusion complexes, being possible to obtain a 0.02% (w/v) tacrolimus concentration by using 40% (w/v) HPβCD aqueous solutions. Formulations also showed good ophthalmic properties in terms of pH, osmolality and safety. Stability studies proved these formulations to be stable for at least 3 months in refrigeration. Ex vivo bioadhesion and in vivo ocular permanence showed good mucoadhesive properties with higher ocular permanence compared to the reference pharmacy compounding used in clinical settings (t_1/2 of 86.2 min for the eyedrop elaborated with 40% (w/v) HPβCD and Liquifilm^® versus 46.3 min for the reference formulation). Thus, these novel eye drops present high potential as a safe alternative for uveitis treatment, as well as a versatile composition to include new drugs intended for topical ophthalmic administration.

Surface functionalized mesoporous silica nanoparticles for intravitreal application of tacrolimus

Tacrolimus (TAC), a potent immunosuppressive macrolide, has been investigated for ocular diseases due to promising results in the treatment of anterior and posterior segments eye diseases. Mesoporous and functionalized silica nanoparticles show potential as TAC delivery platforms owing to their interesting characteristic as large surface area, uniform pore size distribution, high pore volume, and excellent biocompatibility. The purpose of this study was to incorporate TAC in functionalized silica nanoparticles with 3-aminopropyltriethoxysilane (MSNAPTES) and investigate the safety and biocompatibility of the systems. The MSNAPTES and MSNAPTES TAC nanoparticles were characterized. The in vitro cytotoxicity of MSNAPTES and MSNAPTES load with TAC (MSNAPTES-TAC) in retinal pigment epithelial cells (ARPE-19) was determined, chorioallantoic membrane (CAM) assay model was used to investigate the in vivo biocompatibility, and safety of intravitreal injection was evaluated using clinical examination (assessment of intraocular pressure and indirect fundus ophthalmoscopy), electroretinographic (ERG) and histologic studies in rats' eyes. The elemental analysis (CHN), thermogravimetric (TGA), photon correlation spectroscopy and Fourier transform infrared (FTIR) analysis confirmed the presence of functionalized agent and TAC in the MSNAPTES nanoparticles. TAC loading was estimated at 7% for the MSNAPTES TAC nanoparticles. MSNAPTES and MSNAPTES TAC did not present in vitro cytotoxicity. The drug delivery systems showed good biocompatibility on CAM. No retinal abnormalities, vitreous hemorrhage, neovascularization, retinal detachment, and optic nerve atrophy were observed during the in vivo study. Follow-up ERGs showed no changes in the function of the retina cells after 15 days of intravitreal injection, and histopathologic observations support these findings. In conclusion, MSNAPTES TAC was successfully synthesized, and physicochemical analyses confirmed the presence of TAC in the nanoparticles. In vitro and in vivo studies indicated that MSNAPTES TAC was safe to intravitreal administration. Taking into account the enormous potential of MSNAPTES to carry TAC, this platform could be a promising strategy for TAC ocular drug delivery in the treatment of eye diseases.

Amelioration of Endotoxin-Induced Uveitis in Rabbit by Topical Administration of Tacrolimus Proglycosome Nano-Vesicles

This work was aimed to improve the efficacy of tacrolimus in the treatment of endotoxin-induced uveitis (EIU) using propylene glycol modified lipid vesicles termed as proglycosome nano-vesicles (PNVs). PNVs were prepared by modified film hydration method. Experimental uveitis in rabbit eye was induced by an intravitreal injection of 20 μL of the endotoxin solution containing 100 ng of lipopolysaccharide endotoxin. In vivo efficacy of PNVs was determined by studying clinical symptoms of uveitis using slit lamp examination and by quantitatively measuring levels of tumor necrosis factor-alpha, interleukin-6, leukocytes and total proteins in aqueous humor, 24 h after intravitreal injection of endotoxin. Comparison was made with healthy, untreated and tacrolimus solution treated eyes. PNVs developed were nano-sized, deformable and showed sustained release of tacrolimus over period of 12 h. In vivo results indicated statistically significant difference between the effects of PNVs in the treatment of EIU compared to tacrolimus. PNV treatment not only subsides clinical symptoms of uveitis but also prevented breakdown of blood aqueous barrier. Tacrolimus loaded PNVs are potential new topical treatment for uveitis.

Therapeutic efficacy of tacrolimus in vernal keratoconjunctivitis: a meta-analysis of randomised controlled trials

Background and objective

Tacrolimus has been widely used in recent years for treating allergic conjunctivitis, but there is currently no available meta-analysis regarding its therapeutic efficacy. This study systematically evaluated the effectiveness of tacrolimus in the treatment of allergic conjunctivitis.

Methods

Data obtained from literature searches of the PubMed, Cochrane Library, Embase, CNKI, and Wanfang databases were retrieved by combining medical subject words and free words. Literature was selected on the basis of established inclusion and exclusion criteria, and the extracted data were evaluated for risk of bias using RevMan 5.3 for meta-analysis.

Results

A total of 177 articles were retrieved, of which 5 articles were eventually selected, all of which involved tacrolimus treatment for vernal keratoconjunctivitis. A total of 203 samples were analysed. Results of the meta-analysis showed that the tacrolimus treatment group had significantly lower ocular objective sign scores (SMD −1.39, 95% CI −2.50 to −0.27; p<0.05) and had a significantly lower subjective symptom evaluation score (SMD −0.92, 95% CI −1.59 to −0.24; p<0.05) than the control group.

Conclusion

Current evidence shows that tacrolimus is effective in treating vernal keratoconjunctivitis.

Conjunctival Injection Reduction in Patients with Atopic Keratoconjunctivitis Due to Synergic Effect of Bovine Enteric-Coated Lactoferrin in 0.1% Tacrolimus Ophthalmic Suspension

Lactoferrin (LF), a multifunctional glycoprotein found in mammalian milk, is reported to have immunoregulatory effects. The present study aimed to evaluate whether enteric-coated LF (eLF) could improve symptoms in patients with atopic keratoconjunctivitis (AKC). This randomized double-blind placebo-controlled single-center trial comprised Japanese patients (n = 20; aged 22–60 years) with AKC. Patients treated with 0.1% tacrolimus ophthalmic suspension (TALYMUS^®) were administered eLF (400 mg/d of bovine LF) or placebo tablets for 12 weeks. Conjunctival injection was examined, papillae formation in the palpebral conjunctiva was evaluated, and corneal fluorescein score, itchy sensation in end-point itching scale, and serum allergic parameters were assessed. Conjunctival injection was significantly reduced in the LF group than in the placebo group (p = 0.0017, Mann–Whitney U-test). Papillae formation in the palpebral conjunctiva showed a statistical decrease in the LF group than in the placebo group (p = 0.010, unpaired T-test). LF combined with TALYMUS^® could be a promising treatment strategy to mitigate AKC.

A Panel of Broad-Spectrum Antivirals in Topical Ophthalmic Medications from the Drug Repurposing Approach during and after the Coronavirus Disease 2019 Era

The coronavirus disease 2019 (COVID-19) represents a global concern of public health caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Its clinical manifestations are characterized by a heterogeneous group of symptoms and pictures (ranging from asymptomatic to lethal courses). The prevalence of conjunctivitis in patients with COVID-19 is at present controversial. Although it has been reported that only 0.9% developed signs of conjunctivitis, other report indicates that up to 31.6% of hospitalized patients had conjunctivitis. Considering the widespread use of topical ophthalmic medications (e.g., eye drops) by the general population, for various reasons (e.g., artificial tears, anti-glaucoma medications, topical antibiotics, etc.), the existence of their side effects as antiviral action should be investigated in-depth because it could possibly explain the aforementioned controversial data and represent a potential antiviral treatment for SARS-CoV-2 replication/diffusion on the ocular surface. Here, we discuss and elucidate the antiviral side effect of many eye drops and ophthalmic ointments commonly used for others purposes, thus showing that these secondary effects (not to be confused with the 'adverse effects') might be of primary importance in a number of viral infections (e.g., those for which there is no validated treatment protocol), according to a drug repurposing approach. Some active ingredients or excipients described here have activity against other types of viruses, thus suggesting potential broad-spectrum applications.

Stability characterization, kinetics and mechanism of tacrolimus degradation in cyclodextrin solutions

Tacrolimus is a macrolide lactone and potent immunosuppressant. It is highly lipophilic and has very limited aqueous solubility. Tacrolimus is highly susceptible to hydrolysis which results in very limited stability in aqueous solutions. Besides this, tacrolimus also undergoes dehydration and epimerization. Cyclodextrin (CD) complexation can increase the solubility and stability of hydrophobic drugs in aqueous solutions through the formation of drug/CD complexes. The aim of this study was to investigate degradation kinetics, mechanism and stability of tacrolimus in aqueous CD solutions, with the ultimate goal of developing an aqueous vehicle for ophthalmic delivery. For this, phase-solubility and kinetic studies in aqueous solutions containing different CDs at different pH values were performed. Mass spectrometry studies were also performed to elucidate the degradation mechanism of the drug in aqueous CD solution. The study showed that the drug has maximum stability between pH 4 and 6 and hydrolysis was the main cause of tacrolimus degradation in aqueous 2-hydroxypropyl-βCD (HPβCD) solutions. βCD and its derivatives were the better CD solubilizers for tacrolimus. The solubility and stability studies were further conducted with CD and surfactants, which is tyloxapol, tween 80 and poloxamer 407, where the combination provided better results compared to individual components.

Approaches toward enhancing survival probability following deep anterior lamellar keratoplasty

The greatest advantage of deep anterior lamellar keratoplasty over full-thickness corneal transplantation is the elimination of graft failure caused by endothelial rejection. Despite this advantage, a deep anterior lamellar keratoplasty graft can fail because of several factors, such as complications related to the donor-recipient interface, graft epithelial abnormalities, graft vascularization, stromal graft rejection, and recurrence of herpetic keratitis. Increased deep anterior lamellar keratoplasty graft survival is mainly built upon optimization of the ocular surface to provide a hospitable environment for the graft. Any predisposing factors for graft epithelial abnormalities, corneal neovascularization, and preexisting vernal keratoconjunctivitis should be identified and treated preoperatively. Prompt recognition and appropriate treatment of interface-related complications and stromal graft rejection usually result in good anatomic outcomes, with no detrimental effects on vision.

Management of ocular allergy

The treatment and management of ocular allergy (OA) remain a major concern for different specialties, including allergists, ophthalmologists, primary care physicians, rhinologists, pediatricians, dermatologists, clinical immunologists, and pharmacists. We performed a systematic review of all relevant publications in MEDLINE, Scopus, and Web Science including systematic reviews and meta-analysis. Publications were considered relevant if they addressed treatments, or management strategies of OA. A further wider systematic literature search was performed if no evidence or good quality evidence was found. There are effective drugs for the treatment of OA; however, there is a lack an optimal treatment for the perennial and severe forms. Topical antihistamines, mast cell stabilizers, or double-action drugs are the first choice of treatment. All of them are effective in reducing signs and symptoms of OA. The safety and optimal dosing regimen of the most effective topical anti-inflammatory drugs, corticosteroids, are still a major concern. Topical calcineurin inhibitors may be used in steroid-dependent/resistant cases of severe allergic keratoconjunctivitis. Allergen-specific immunotherapy may be considered in cases of failure of first-line treatments or to modify the natural course of OA disease. Based on the current wealth of publications and on the collective experience, recommendations on management of OA have been proposed.

Immune reactions after modern lamellar (DALK, DSAEK, DMEK) versus conventional penetrating corneal transplantation

In the past decade, novel lamellar keratoplasty techniques such as Deep Anterior Lamellar Keratoplasty (DALK) for anterior keratoplasty and Descemet stripping automated endothelial keratoplasty (DSAEK)/Descemet membrane endothelial keratoplasty (DMEK) for posterior keratoplasty have been developed. DALK eliminates the possibility of endothelial allograft rejection, which is the main reason for graft failure after penetrating keratoplasty (PK). Compared to PK, the risk of endothelial graft rejection is significantly reduced after DSAEK/DMEK. Thus, with modern lamellar techniques, the clinical problem of endothelial graft rejection seems to be nearly solved in the low-risk situation. However, even with lamellar grafts there are epithelial, subepithelial and stromal immune reactions in DALK and endothelial immune reactions in DSAEK/DMEK, and not all keratoplasties can be performed in a lamellar fashion. Therefore, endothelial graft rejection in PK is still highly relevant, especially in the "high-risk" setting, where the cornea's (lymph)angiogenic and immune privilege is lost due to severe inflammation and pathological neovascularization. For these eyes, currently available treatment options are still unsatisfactory. In this review, we will describe currently used keratoplasty techniques, namely PK, DALK, DSAEK, and DMEK. We will summarize their indications, provide surgical descriptions, and comment on their complications and outcomes. Furthermore, we will give an overview on corneal transplant immunology. A specific focus will be placed on endothelial graft rejection and we will report on its incidence, clinical presentation, and current/future treatment and prevention options. Finally, we will speculate how the field of keratoplasty and prevention of corneal allograft rejection will develop in the future.

Monotherapy of topical tacrolimus 0.03% in the treatment of vernal keratoconjunctivitis in the pediatric population

PURPOSE

To report the results of treating children with vernal keratoconjunctivitis (VKC) using a monotherapy of topical tacrolimus 0.03%.

METHODS

This was a prospective, nonrandomized observational study of children newly diagnosed with VKC. The severity of the disease was graded on a 4-point scale of symptoms and signs. Patients were treated with tacrolimus 0.03% ointment and were followed for 8 months according to a schedule based on the severity of the disease. The primary measure of treatment efficacy was the change in the score of objective signs. The incidence and severity of adverse events, if any, were recorded.

RESULTS

A total of 45 children aged 5-15 years were enrolled. The mean composite symptom score was 6.84 ± 2.26 at baseline and 0.71 ± 1.62 at 8 months, a statistically significant reduction (P < 0.001). The mean composite sign score was 9.6 ± 3.14 at baseline and 1.16 ± 1.28 at 8 months, also a statistically significant reduction (P < 0.001). Four patients had to be started on steroids within the first month of treatment and were considered treatment failures. Thus, 89% of patients showed significant improvement. No participant experienced adverse effects, although some reported a transient stinging sensation.

CONCLUSIONS

In our study cohort topical tacrolimus ointment 0.03% as a monotherapy for VKC was successful in the majority of subjects, and there was no adverse effect.

Topical Tacrolimus for Corneal Subepithelial Infiltrates Secondary to Adenoviral Keratoconjunctivitis

PURPOSE

The objective of this study was to determine the efficacy and safety of topical tacrolimus compounded in the Pharmacy Service for the treatment of subepithelial corneal infiltrates (SEIs) secondary to adenoviral keratoconjunctivitis.

METHODS

This retrospective study included patients who had been dispensed topical tacrolimus for the treatment of SEIs during the previous year. Patients were treated with tacrolimus 0.03% eye drops twice daily or tacrolimus 0.02% ointment once daily. The following data were recorded: length of treatment, visual acuity before and after treatment, intraocular pressure before, during, and at the end of treatment, previous treatments, and the presence of SEIs after treatment. The subjective symptoms of the patients were also assessed.

RESULTS

Fifty-five patients (85 eyes) were included, 54.5% with bilateral involvement. A total of 31 (36.5%) eyes were treated with tacrolimus ointment and 54 eyes (63.5%) with tacrolimus eye drops. The median length of treatment was 185 days (p25-75: 93.5-426), and the mean follow-up duration was 363 days (p25-75: 148-540). In 62.35% of the eyes, the SEIs were reduced in number and size, and in 31.76%, they were eliminated. The patients had better visual acuity after treatment with highly statistically significant differences. Tolerance was good overall, being better in the eye drops group.

CONCLUSIONS

Topical tacrolimus, compounded in the pharmacy, seems to be an effective and safe alternative for the treatment of SEIs secondary to adenovirus keratoconjunctivitis.

Vernal keratoconjunctivitis

Vernal keratoconjunctivitis (VKC) is a chronic allergic conjunctivitis that is most often seen in young, males. Although most types of allergic conjunctivitis do not affect vision, VKC is unusual in that damage to the cornea from the condition can result in vision loss. Although it is typically seasonal, year-round symptoms can be seen, which can lead to uncertain diagnoses being made. Although the pathophysiology of VKC is better understood in recent years, allowing more targeted therapies, management of these patients can still be very challenging, and complications can occur. As such, aggressive management of VKC is necessary, especially since vision loss in the amblyogenic age range can be permanent.

Topical tacrolimus in anterior segment inflammatory disorders

Immune mediated inflammatory anterior segment diseases are variable and their management requires intense immunosuppression. Treatment with topical steroids is associated with serious ocular side effects. In order to overcome the potentially blinding complications of topical steroids, immunomodulatory drugs are being used more frequently. Tacrolimus is a calcineurin inhibitor that induces suppression of T lymphocytes activity and reduction of ocular inflammation. Tacrolimus was recently investigated for application in various anterior segment inflammatory disorders. In this review, we will discuss the therapeutic application of topical tacrolimus as a steroid-sparing agent in treating T cell mediated anterior segment inflammation.

Long-term use of 0.003% tacrolimus suspension for treatment of vernal keratoconjunctivitis

PURPOSE:

To evaluate the safety and efficacy of 0.003% tacrolimus suspension for the treatment of refractory vernal keratoconjunctivitis (VKC).

MATERIALS AND METHODS:

This prospective study included 40 eyes of 20 patients with severe VKC. After discontinuing all other medications, patients were treated with varying doses of 0.003% tacrolimus suspension. All were followed for at least 24 months. Changes in signs and symptoms after treatment were evaluated; adverse events were assessed. The clinical response to the treatment was the most important measurement to achieve the conclusion.

RESULTS:

The mean age of the patients was 15.7 ± 1.4 years. Two patients discontinued treatment due to severe burning sensation and were excluded from the study. Significant improvements in all signs and symptoms, including itching, foreign body sensation, papillae, and Trantas dots, were seen in all patients 6 weeks after starting topical tacrolimus. Itching was the first symptom to improve. Treatment was gradually reduced, and intervals were increasing between applications. Recurrence occurred in all patients who attempted to discontinue treatment. No additional medications were required to provide relief, and no significant changes in visual acuity or refraction were seen.

CONCLUSIONS:

The safety and efficacy of 0.003% Tacrolimus suspension treatment for refractory VKC were achieved and it can be considered a useful option instead of steroids, despite the poor compliance in few patients due its adverse effects.

Steroid-Sparing Effect of 0.1% Tacrolimus Eye Drop for Treatment of Shield Ulcer and Corneal Epitheliopathy in Refractory Allergic Ocular Diseases

PURPOSE

To evaluate the effects of 0.1% topical tacrolimus alone or in combination with steroids for the treatment of shield ulcers and corneal epitheliopathy in patients with refractory allergic ocular diseases.

DESIGN

Open cohort study.

PARTICIPANTS

Patients with refractory allergic conjunctivitis epitheliopathy, shield ulcers, or corneal plaques (N = 791).

METHODS

The 791 patients were treated with topical tacrolimus alone or in combination with topical or oral steroids. The effectiveness of the treatments was determined by a corneal epitheliopathy score during the 3-month follow-up period. The clinical signs were rated on a 4-grade scale. Corneal epitheliopathy with no corneal staining was graded as 0, and shield ulcers or plaques were graded as 3, the highest grade. The effects of tacrolimus with and without topical steroids on the epitheliopathy scores were assessed after adjustments for the severity of the clinical signs and characteristics.

MAIN OUTCOME MEASURES

Changes in the corneal epitheliopathy score.

RESULTS

Adjusted mean epitheliopathy score at the baseline was 1.73 (95% confidence interval [CI], 1.65-1.81) for patients treated with tacrolimus alone, and this was significantly reduced by -0.93 at 1 month. The reduction of the score by topical and oral steroids was -0.02 for fluorometholone, 0.02 for betamethasone, and -0.02 for oral steroids, and these reductions were not significant compared with the reduction effect of topical tacrolimus alone at -0.93. The 238 patients with shield ulcer (score 3) were analyzed with adjustments, and the mean epitheliopathy score at 1 month was reduced to 1.38 with tacrolimus alone (95% CI, 1.24-1.51), 1.41 (95% CI, 1.26-1.56) with adjuvant fluorometholone, and 1.46 (95% CI, 1.32-1.61) with adjuvant betamethasone. No significant difference was observed in the adjunctive topical steroids. The presence of severe palpebral conjunctival symptoms, including giant papillae, was a significant resisting factor for topical tacrolimus.

CONCLUSIONS

The significant effects of topical tacrolimus alone on shield ulcers and corneal epitheliopathy suggest that it may be used without the need for steroids.

Morphological assessment of the retina in uveitis

Background

The objective of this study is to describe a system for color photograph evaluation in uveitis and report baseline morphologic findings for the Multicenter Uveitis Steroid Treatment (MUST) Trial.

Four-hundred seventy-nine eyes of 255 subjects with intermediate, posterior, and panuveitis had stereoscopic color fundus photographs obtained by certified photographers and evaluated by certified graders using standardized procedures to evaluate morphologic characteristics of uveitis. The posterior pole was evaluated for macular edema, vitreoretinal interface abnormalities, and macular pigment disturbance/atrophy; the optic disk was assessed for edema, pallor, or glaucomatous changes. The presence of neovascularization, vascular occlusion, vascular sheathing, and tractional retinal changes was determined. A random subset of 77 images was re-graded to determine the percentage agreement with the original grading on a categorical scale.

Results

At baseline, 437/479 eyes had images available to grade. Fifty-three eyes were completely ungradable due to media opacity. Common features of intermediate and posterior/panuveitis were epiretinal membrane (134 eyes, 35 %), and chorioretinal lesions (140 eyes, 36 %). Macular edema was seen in 16 %. Optic nerve head and vascular abnormalities were rare. Reproducibility evaluation found exact agreement for the presence of chorioretinal lesions was 78 %, the presence and location of macular edema was 71 %, and the presence of epiretinal membrane was 71 %. Vertical cup-to-disk ratio measurement had intra-class correlation of 0.75.

Conclusions

The MUST system for evaluating stereoscopic color fundus photographs describes the morphology of uveitis and its sequelae, in a standardized manner, is highly reproducible, and allows monitoring of treatment effect and safety evaluation regarding these outcomes in clinical trials.

Electronic supplementary material

The online version of this article (doi:10.1186/s12348-016-0103-2) contains supplementary material, which is available to authorized users.

Tacrolimus Ointment for Treatment of Vernal Keratoconjunctivitis

Purpose:

To evaluate the safety and efficacy of tacrolimus 0.1% ointment for the treatment of refractory vernal keratoconjunctivitis (VKC).

Materials and Methods:

This prospective, nonrandomized case series enrolled 20 patients (40 eyes) with severe VKC, who were treated with tacrolimus 0.1% ointment. The mean age of the patients was 18.25 ± 4.2 years (range, 9–31 years). Each patient completed a follow-up period of at least 24 months. The main outcome measure was the clinical response to treatment.

Results:

Significant improvements in clinical signs and symptoms were achieved in all patients 6 weeks after starting treatment with topical tacrolimus. Treatment was gradually reduced, with increasing intervals between applications. VKC recurred in all patients who attempted to discontinue treatment. No additional medications were required and no significant changes in visual acuity or refraction were documented. Five patients discontinued treatment due to a severe burning sensation and were excluded from the study.

Conclusions:

Tacrolimus, 0.1% ointment, is a safe and effective treatment for VKC refractory to standard treatment and may be used as a substitute for steroid treatments used to controlled disease activity. However, adverse effects could cause poor patient compliance.

Ocular Graft-Versus-Host Disease: A Review

Hematopoietic stem cell transplantation is important in the management of several lymphoproliferative and bone marrow disorders. Graft-versus-host disease (GVHD) involves inflammatory manifestations that arise after transplant and can affect many organs. Ocular manifestations of GVHD are common, and eye care providers must understand this disease entity. The ocular surface is most commonly involved, but GVHD can affect all parts of the eye. Ocular GVHD can be relapsing and remitting, can decrease quality of life, and can be challenging to diagnose and adequately treat. The diagnostic criteria for and grading of ocular GVHD continue to evolve. This review aims to summarize current definitions, clinical findings, diagnostic criteria, and management of ocular GVHD. The care of patients with ocular GVHD requires a multidisciplinary approach.

Long-term result of maintenance treatment with tacrolimus ointment in chronic ocular graft-versus-host disease

PURPOSE

To investigate the efficacy and safety of long-term maintenance treatment with tacrolimus ointment in chronic ocular graft-vs-host disease (GVHD) with ocular surface inflammation.

DESIGN

A retrospective interventional consecutive case series.

METHOD

Long-term maintenance treatment (≥6 months) with topical 0.02% tacrolimus ointment was applied to patients with chronic ocular GVHD with ocular surface inflammation (at least grade 2 inflammatory score). We evaluated the inflammatory score, steroid score and steroid use period of total duration, and numbers of inflammatory aggravations before and after tacrolimus treatment. The clinical outcomes were assessed by symptom score, ocular surface staining, Schirmer I test, tear break-up time (TBUT), and classification of chronic GVHD conjunctivitis at the initial and final examinations.

RESULTS

Thirteen patients (24 eyes) were treated with tacrolimus ointment for up to 20 months (average 12.2 months). The ocular surface inflammatory score decreased from 2.8 to 0.6 (P = .001) within 2-8 weeks after starting tacrolimus ointment treatment. The numbers of inflammatory aggravation and the need for steroid treatment also decreased after initiating tacrolimus treatment. At the final follow-up, all patients reported improvement in clinical outcomes, compared to initial findings. Except for blurred vision or mild burning sensation, there were no reported side effects.

CONCLUSION

Considering the chronic course of GVHD, long-term maintenance treatment with tacrolimus ointment could be useful and safe to locally treat ocular surface inflammation in chronic ocular GVHD.

In vitro and in vivo release characteristics of Tacrolimus (FK506) from an episcleral drug-delivery implant

PURPOSE

To investigate the in vitro and in vivo release characteristics of Tacrolimus (FK506) from an episcleral drug-delivery implant.

METHODS

For in vitro experiments, Tacrolimus-loaded implants (0.5 mL; at concentrations of 0.25, 0.5, and 1.0 mg/mL) were immersed in a balanced salt solution. Samples of the surrounding liquid were aspirated at different times over a 96-h period. For in vivo experiments, the experimental group received an implant loaded with Tacrolimus (0.5 mg/mL; 0.5 mL); the control group was given a subconjunctival injection of 0.5 mL Tacrolimus (0.5 mg/mL). On postoperative days 3, 7, 14, 28, and 56, 3 animals were sacrificed, and their eyes were enucleated. Tacrolimus concentrations were determined by liquid chromatographic-tandem mass spectrometry. Ocular toxicity was evaluated by slit-lamp photography, fundus photography, intraocular pressure (IOP), and histology.

RESULTS

The implants released Tacrolimus in a biphasic pattern for 96 h in the in vitro study. The release kinetics were not dependent on the drug concentrations. The in vivo study showed statistically significant differences between the 2 treatment groups. Tacrolimus levels were particularly high in the conjunctiva, iris, ciliary body, cornea, sclera, choroid, and retina in the experimental group, while concentrations were low and only lasted for 1 week in the controls. Slit-lamp photography, fundus photography, IOP, and histology showed no evidence of toxic effects.

CONCLUSIONS

The episcleral drug-delivery implant mechanically released Tacrolimus through the apertures of capsules and, consequently, may be a promising drug vehicle for the treatment of immune-mediated ocular disorders.

Therapeutic effects of 0.1% tacrolimus eye drops for refractory allergic ocular diseases with proliferative lesion or corneal involvement

Background

The objective of this study was to investigate the efficacy of topical 0.1% tacrolimus in treating refractory allergic conjunctivitis with proliferative lesions and/or corneal involvement.

Methods

This prospective observational study included 1436 patients with refractory allergic conjunctivitis whose condition had responded poorly to conventional antiallergic drugs and/or topical steroids and/or topical cyclosporine. All patients received tacrolimus eye drops twice daily during the study period. Ten clinical signs and six clinical symptoms were rated on a four-grade scale. The primary endpoint was the change from baseline in total clinical signs and symptoms score at the last observation or following 6 months of treatment.

Results

Total signs and symptoms score significantly decreased after 1 month of treatment (p<0.001). Giant papillae and corneal lesions were also reduced by tacrolimus eye drop use (p<0.001). The drug proved effective in patients whose condition did not respond well to topical cyclosporine therapy. About 50% of all patients using topical steroids were weaned. The most common adverse reaction was a transient burning sensation (3.20%).

Conclusions

Tacrolimus eye drops are highly effective in treating refractory allergic conjunctivitis with proliferative lesions and/or corneal involvement, and may reduce or replace topical steroid use.

Trial registration number

UMIN 000008640.

Evaluation of the pharmacokinetics and ocular tolerance of a microemulsion containing tacrolimus

PURPOSE

Tacrolimus is a potent immunosuppressive agent with limited corneal penetration. Microemulsions can increase the drug solubility and enhance drug absorption in the eye. This work aimed to develop a tacrolimus microemulsion as well as to characterize and to evaluate its ocular tolerance and pharmacokinetics after topical application in rabbits.

METHODS

The microemulsion was prepared by the titration with the cosurfactant technique and its physical-chemical parameters and stability were determined. The cytotoxicity was evaluated using the corneal epithelium and conjunctiva cell lines. The ocular pharmacokinetic parameters in rabbits were determined and compared with that obtained after instillation of tacrolimus suspension.

RESULTS

The microemulsion containing tacrolimus was successfully developed. It was nonirritating to rabbits' eyes and it was also not toxic to the corneal and conjunctival cells. When compared to the suspension, the microemulsion containing tacrolimus presented higher values of AUC (2,912.5±245.4 min.ng/mL vs. 1,669.8±93 min.ng/mL) and Cmax (26.8±2.3 ng/mL vs. 20.7±2.8 ng/mL). On the other hand, the Cl/F value was smaller when compared to the suspension that may decrease the number of applications of eye drops.

CONCLUSION

The developed microemulsion could be an alternative to reduce the systemic adverse effects of tacrolimus and, consequently, increase the patient compliance to the treatment.