Topical liposome-encapsulated FK506 for the treatment of endotoxin-induced uveitis

Treatment of Steroid-Resistant Nodular Episcleritis With Tacrolimus: A Case Report

A 46-year-old male, with no chronic medical illness, complained of pain, tearing, and redness for one-month duration, with no photophobia, discharge, or decrease in visual acuity. Examination revealed a small, painful, red swelling in the left sclera. Slit-lamp examination using a narrow bright slit beam revealed edema of the episcleral layer and injection of the superficial episcleral blood vessels. The rest of the anterior segment exam and fundoscopy were normal. The laboratory investigations and systemic workup were normal. The patient was initially treated with prednisolone acetate (Pred Forte) 1% every three hours per day for one week, and then four times per day for another week, and tapered gradually over eight weeks with systemic nonsteroidal anti-inflammatory drugs (NSAIDs) as diclofenac sodium for eight weeks with mild improvement of clinical symptoms, but the size of the lesion remained without any change and the patient started to have a relapse of symptoms at the end of the course. Topical tacrolimus drops of 0.1% concentration were prepared in the pharmacy under complete sterile precautions and were used four times per day for the following six weeks duration instead of the initial therapy (steroids and NSAIDs). Tacrolimus drops were then tapered gradually over another six weeks duration. The patient showed dramatic suppression of inflammation and exceptional remission of symptoms with complete resolution of the episcleritis. Topical tacrolimus is very effective in the treatment of nodular episcleritis, which is resistant to steroid therapy. Patients with nodular episcleritis suffer from prolonged bouts of inflammation that are characteristically more painful than the diffuse type and may be associated with other systemic diseases. The case is steroid-resistant nodular episcleritis, which did not respond to the usual treatment and showed a good response to treatment with tacrolimus, which was first introduced in episcleritis. Tacrolimus is being used in other ocular diseases, but its use in episcleritis is unique.

Inhibition of Neovascularization and Inflammation in a Mouse Model of Corneal Alkali Burns Using Cationic Liposomal Tacrolimus

Eye drops account for more than 90% of commercialized ophthalmic drugs. However, eye drops have certain shortcomings, such as short precorneal retention time and weak corneal penetration. The requirement of frequent instillation of eye drops also causes poor patient compliance, which may lead to further aggravation of the disease. We aimed to develop a cationic liposome formulation to increase the bioavailability of the therapeutic agent and solve the aforementioned problems. In the present study, we prepared cationic liposomal tacrolimus (FK506) with a surface potential of approximately +30 mV, which could bind to the negatively charged mucin layer of the ocular surface. Our results showed that the content of FK506 in the cornea was increased by 93.77, 120.30, 14.24, and 20.36 times at 5, 30, 60, and 90 min, respectively, in the FK506 liposome group (0.2 mg/ml) compared with the free drug group (0.2 mg/ml). Moreover, FITC-labeled FK506 liposomes significantly prolonged the ocular surface retention time to 50 min after a single dose. In addition, the results of the Cell Counting Kit-8 assay, live and dead cell assay, sodium fluorescein staining, and hematoxylin and eosin staining all indicated that FK506 liposomes had good biological compatibility in both human corneal epithelial cells and mouse eyeballs. Compared with the free drug at the same concentration, FK506 liposomes effectively inhibited vascular endothelial growth factor-induced green fluorescent protein-transduced human umbilical vein endothelial cell migration and tube formation in vitro. In a mouse corneal neovascularization model induced by alkali burns, FK506 liposomes (0.2 mg/ml) enhanced corneal epithelial recovery, inhibited corneal neovascularization, and reduced corneal inflammation, and its therapeutic effect was better than those of the commercial FK506 eye drops (1 mg/ml) and the free drug (0.2 mg/ml). Collectively, these results indicate that cationic FK506 liposomes could increase the efficacy of FK506 in the corneal neovascularization model. Therefore, cationic FK506 liposomes can be considered as a promising ocular drug delivery system.

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.

Aqueous penetration of topical tacrolimus

Purpose

To evaluate the penetration of topical tacrolimus 0.05% into the aqueous humor.

Observations

A total of four patients scheduled for routine cataract surgery were included prospectively. We excluded patients with corneal pathology or ocular surface diseases. Topical tacrolimus 0.05% was compounded at our facility. It was dosed every 1 min for 5 min an hour before the aqueous was sampled. Aqueous samples were collected at the time of cataract surgery and were subjected to detection of presence and level of tacrolimus. There were 2 male and 2 female patients. The age range was 58–73 years with a mean age of 66 years. Tacrolimus was detected in the aqueous humor in all patients. The concentration of tacrolimus in the aqueous ranged from 2.6 to 5.6 ng/ml (mean 4.15 ± 1.18 ng/ml). In all patients, the aqueous tacrolimus concentration was greater than the minimal therapeutic level. The study was registered at clinicaltrials.gov (registration number is NCT02794610).

Conclusions and Importance

Tacrolimus was detected in the aqueous humor following topical application. Topical tacrolimus may be a promising steroid-sparing modality for the treatment of anterior uveitis.

Evaluation of subconjunctival liposomal steroids for the treatment of experimental uveitis

Non-infectious anterior uveitis (AU) is a potentially sight threatening inflammatory condition. The current gold standard for treatment is topical steroids, but low ocular bioavailability and compliance issues with the intensive dosing regimen limit the efficacy of this treatment. Liposomes as a drug delivery system may help to overcome these problems. We studied the efficacy of a PEG-liposomal formulation of liposomal steroids, administered as a single subconjunctival dose, in the treatment of experimental uveitis in rabbit eyes. Rabbits that received subconjunctival liposomal triamcinolone acetonide phosphate (LTAP) or liposomal prednisolone phosphate (LPP) had significantly lower mean inflammatory scores than untreated controls on Day 4 after induction of uveitis (LPP vs controls, p = 0.049) and 8 (LPP vs controls, p = 0.007; LTAP vs controls, p = 0.019), and lower scores than rabbits given topical PredForte1% 4 times a day on Day 8 (p = 0.03). After antigen rechallenge, the subconjunctival liposomal steroid groups continued to have greater suppression of inflammation than untreated controls on Day 11 (p = 0.02). Localization of liposomes in inflamed ocular tissue was confirmed by histology and immunostaining, and persisted in the eye for at least one month. Our study demonstrates that a single subconjunctival injection of liposomal steroids induces effective and sustained anti-inflammatory action.

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 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.

Application for tacrolimus ointment in treating refractory inflammatory ocular surface diseases

PURPOSE

To evaluate the therapeutic effects of topical tacrolimus ointment on refractory inflammatory ocular surface diseases.

DESIGN

Retrospective interventional consecutive case series.

METHODS

In Severance Hospital, Seoul, South Korea, 0.02% tacrolimus ointment was topically applied 1 to 3 times per day, depending on disease severity, for up to 31 months in eyes of 12 consecutive patients with refractory inflammatory ocular surface diseases who had previously been treated with steroid therapy. Seven patients had chronic cicatrizing conjunctivitis (6 cases caused by Stevens-Johnson syndrome and 1 attributable to ocular cicatricial pemphigoid); 4 had scleritis (3 necrotizing scleritis, 1 recurrent nodular scleritis); and 1 patient had Mooren ulcer with corneal perforation. The therapeutic outcomes after tacrolimus treatment were evaluated according to the following criteria: change in clinical findings (eg, decrease of hyperemia, ocular pain, epithelial defect, and pseudomembrane), intraocular pressure (IOP), and need for steroid therapy.

RESULTS

In all 3 groups, tacrolimus showed an immunosuppressive effect, especially on scleritis and Mooren ulcer. These effects included suppression of corneoscleral melting and reduction of hyperemia. In chronic cicatrizing conjunctivitis, simultaneous topical tacrolimus while tapering steroid therapy suppressed inflammatory relapse. The elevated IOP in steroid responders recovered to normal range after successful tapering of steroid. No adverse side effects were noted after 1.5 to 31 months of continuous tacrolimus treatment.

CONCLUSION

The use of topical tacrolimus ointment is effective in controlling refractory inflammatory ocular surface disease, and can reduce the need for steroid use while reducing inflammation recurrence.

Therapeutic effect of 0.03% tacrolimus ointment for ocular graft versus host disease and vernal keratoconjunctivitis

Purpose

To determine whether topical tacrolimus might prove effective in the treatment of refractory anterior segment inflammatory diseases, and to evaluate its efficacy in eyes with ocular graft versus host disease (GVHD), and vernal keratoconjunctivitis (VKC).

Methods

Twenty-eight eyes of 14 patients with anterior segment inflammation refractory to steroid treatment were treated with 0.03% tacrolimus ointment at the Samsung Medical Center, Seoul, Korea from March 2008 through August 2009. Seven patients had ocular GVHD and seven had VKC. We evaluated the conjunctival and corneal inflammatory change at one, two, four, and eight weeks after treatment with a scoring system. Time to initial response of treatment and therapeutic effect between GVHD and VKC was also analyzed. After the eight-week treatment period, patients were divided into two groups (maintenance group and discontinuance group). Eight patients maintained the treatment for an additional four months, and six patients discontinued the treatments. Therapeutic effect was also compared between the groups at eight weeks and six months after treatment.

Results

The mean conjunctival and corneal inflammation score was reduced significantly at eight weeks after treatment (p < 0.0001). The therapeutic effect in conjunctival inflammation was first noted at week two after the initial treatment (p = 0.002); reduction in corneal inflammation was first noted at one week (p = 0.0009). When compared according to diagnosis, no therapeutic difference was detected between the groups (p > 0.05). Six months after treatment, we noted no therapeutic differences between the maintenance group and discontinuance group (p > 0.05).

Conclusions

0.03% tacrolimus ointment was safe and effective for use in anterior segment inflammatory disease refractory to steroid.

Preliminary study of the effect of FK506 nanospheric-suspension eye drops on rejection of penetrating keratoplasty

OBJECTIVE

The aim of this study was to investigate the effect of a topical FK506 nanospheric suspension in a rat model of penetrating keratoplasty.

METHODS

FK506 nanospheres were prepared by using a biodegradable poly (lactic-co-glycolic acid) copolymer (PLGA). Its distribution in the eye and blood after a single instillation was examined in rabbits. Sprague-Dawley (SD) rats received corneal heterografts and were topically treated with phosphate-buffered saline (PBS), PLGA, FK-506 0.01% (nanospheres), or dexamethasone 0.05% solutions twice a day for 28 days. Rejection index and graft-survival time were recorded and compared between the four groups. Three grafts were collected at different time points for immunohistochemical studies.

RESULTS

In the cornea, the FK-506 concentration reached its peak within 1 h of a single eye-drop instillation and then decreased by half (1667.85 +/- 611.87 ng/g) at 8 h. FK-506 cannot be detected in rabbit blood. There were significant differences in the graft-survival time between the FK-506 nanosphere group (15.09 +/- 4.81 days) and the other three groups [PBS (7.90 +/- 1.20, t = -4.594, P < 0.001), PLGA (8.44 +/- 0.88, t = - 4.074, P = 0.001) and dexamethasone (10.44 +/- 1.42, t = -2.790, P = 0.012)]. The rejected corneas in the FK506 nanosphere group showed significantly fewer CD4, CD8, CD68, CD79, vascular endothelial growth factor, ICAM, and tumor growth factor-beta(1)-positive cells than those in the other groups.

CONCLUSIONS

FK506 0.01% nanospheric-suspension eye drops delayed the occurrence of corneal allograft rejection and prolonged allograft survival time. The FK506 nanospheres may be valuable in suppressing corneal graft rejection.

Penetration of topically applied tacrolimus into the aqueous humor in Behçet's disease

We investigated the concentration of tacrolimus in aqueous humor, and serum of patients with ocular Behçet's disease after topical application in 11 patients. All received 1 drop of isotonic tacrolimus solution 0.3% every 6 hours for 3 days. The mean tacrolimus concentration in the aqueous and serum, as measured by microparticle enzyme immunoassay, were 12.49 and 0.76 ng/mL, respectively. Tacrolimus may be a promising treatment modality in anterior uveitis in Behçet's disease by topical application.

Formulation of Sirolimus Eye Drops and Corneal Permeation Studies

The aim of this study was the development of eye drops with 1 mg/mL sirolimus and the evaluation of the drug's ability to permeate the freshly isolated pig cornea. Cyclodextrin solutions, liposomes, hydrotrope mixtures, poloxamer gels, and a microemulsion were tested for their suitability to dissolve the extremely hydrophobic drug sirolimus (solubility in water 2.6 microg/mL). The drug content in the formulations was determined by high-performance liquid chromatography, whereas this method is not sensitive enough for the quantification of therapeutic concentrations (7-12 ng/mL). Thus, the acceptor samples of the permeation tests were examined by microparticle enzyme immunoassay. A microemulsion is a suitable vehicle to prepare eye drops with sufficient sirolimus concentrations of 1 mg/mL in a formulation with acceptable tolerance and satisfactory stability over 12 months. However, the drug cannot permeate the intact cornea. After removal of the corneal epithelium, drug concentrations in the acceptor sample reach the lower limit of therapeutical levels. Conclusively, the present sirolimus eye drops might be promising therapeutic tools for the immunomodulatory treatment of ocular surface disorders, such as keratoconjunctivitis sicca, vernal conjunctivitis, or atopical blepharitis. They are not suitable to achieve therapeutic concentrations in the aqueous humour of patients with intact cornea.

Topical tacrolimus ointment for treatment of refractory anterior segment inflammatory disorders

PURPOSE

To report 4 cases of patients treated with topical tacrolimus ointment 0.03% for ocular inflammatory conditions refractory to traditional treatment.

METHODS

Four patients were treated topically with tacrolimus 0.03% ointment twice daily: 2 patients with blepharokeratoconjunctivitis, 1 patient with severe atopic keratoconjunctivitis, and 1 patient with chronic follicular conjunctivitis.

RESULTS

Three patients had a dramatic improvement of their ocular condition as early as 2 weeks after starting tacrolimus ointment. One patient developed a herpes simplex virus dendrite after 1 week of tacrolimus use.

CONCLUSION

Tacrolimus ointment appears to be an effective alternative for certain ocular inflammatory conditions refractory to traditional treatments. There may be an increased risk of herpes simplex virus keratitis associated with topical use. Our results support previous literature of patients benefiting from topical tacrolimus use.

Immunomodulatory Therapy in Ophthalmology – Is There a Place for Topical Application?

Topical corticosteroids, although effective in the treatment of ocular immune-mediated diseases, are well known for their ocular side-effects. Not surprisingly, a variety of alternative immunomodulatory agents have been tested for topical use including cyclosporin A (CsA), mycophenolate mofetil (MMF), tacrolimus (FK506), rapamycin (sirolimus) and leflunomide. Local application bears the possibility to avoid the severe side-effects of systemic therapy. The effect of topical therapy is naturally restricted to local immune response mechanisms, such as antigen presentation by Langerhans and dendritic cells. Moreover, many immunomodulatory agents (e.g. CsA) are lipophilic and thus have low water solubility and penetrate insufficiently intra-ocularly, often being stored in the lipophilic corneal epithelial barrier. Therefore, the therapeutical success is limited for intra-ocular immune-mediated diseases like anterior uveitis. However, a multitude of strategies have been introduced to circumvent these problems including complexing substances such as cyclodextrins (CDs) and liposomes. In the prevention and treatment of transplant rejection after keratoplasty, many attempts to introduce topical immunomodulatory therapy have failed; on the other hand, further therapeutic options not primarily expected are being evaluated today such as treatment of severe keratoconjunctivitis sicca. In our own studies, we investigated the pharmacokinetics of topical treatment with different agents including MMF and evaluated the efficacy of topical treatment in animal models for uveitis and keratoplasty. Taken together, topical immunomodulatory therapy will not replace systemic therapy but further treatment options can be expected.

Successful therapy of refractory pyoderma gangrenosum and periorbital phlegmona with tacrolimus (FK506) in ulcerative colitis

We describe two male patients with ulcerative colitis and refractory pyoderma gangrenosum including periorbital phlegmona in one case. Both patients were successfully managed with low dose oral tacrolimus (0.1 mg/kg bodyweight per day). Serum trough levels were closely monitored and maintained between 4 and 6 ng/mL. A rapid response was noted in both cases. Complete non-scarring skin restitution without side effects was accomplished in both cases. Low dose oral tacrolimus provides a valuable alternative treatment option for IBD patients with refractory pyoderma gangrenosum.

Tacrolimus suppresses tumour necrosis factor-alpha and protects against splanchnic artery occlusion shock

1. Tumour necrosis factor (TNF-alpha) is a pleiotropic cytokine which is deeply involved in the pathogenesis of splanchnic artery occlusion (SAO) shock. Tacrolimus, formerly known as FK506, is a macrolide antibiotic, that blocks the transcription of several proinflammatory cytokines including TNF-alpha. 2. Male anaesthetized rats were subjected to clamping of the splanchnic arteries for 45 min. This surgical procedure resulted in an irreversible state of shock (SAO shock). Sham operated animals were used as controls. SAO shocked rats had a decreased survival rate (0% at 4 h of reperfusion, while sham shocked rats survived more than 4 h), enhanced serum TNF-alpha concentrations (415+/-12 U ml(-1)), decreased mean arterial blood pressure (MAP), leukopenia and increased ileal leukocyte accumulation studied by means of myeloperoxidase activity (MPO=7.5+/-0.3 U g(-1) tissue). Moreover aortic rings from shocked rats showed a marked hyporeactivity to phenylephrine (PE, 1 nM - 10 microM), reduced responsiveness to acetylcholine (ACh, 10 nM - 10 microM) and increased staining for intercellular adhesion molecule-1 (ICAM-1). Furthermore increased mRNA for TNF-alpha was observed in peritoneal macrophages of SAO shocked rats. 3. Tacrolimus (100 microg kg(-1), 5 min after splanchnic arteries occlusion) increased survival rate (SAO + Tacrolimus = 100% at 4 h of reperfusion), reverted the marked hypotension, reduced serum TNF-alpha (15+/-3 U ml(-1)), ameliorated leukopenia, reduced ileal MPO (0.9+/-0.01 U g(-1) tissue), restored to control values the hyporeactivity to PE. improved the reduced responsiveness to ACh and blunted the enhanced immunostaining for ICAM-1 in the aorta. Finally tacrolimus suppressed cytokine mRNA levels in peritoneal macrophages. 4. The data suggest that tacrolimus may represent a new therapeutic approach in circulatory shock.