Daclizumab for treatment of birdshot chorioretinopathy

Efficacy and safety of abatacept to treat active birdshot uveitis: a prospective open label interventional proof-of-concept trial

BACKGROUND/AIMS

Birdshot uveitis (BU) is a chronic autoimmune posterior uveitis, mostly affecting middle-aged Caucasians. There is a strong association with HLA-A29 and T-cell activation. Safety and efficacy of abatacept, an inhibitor of T-cell costimulation, is tested in active BU.

METHODS

Fifteen patients with active BU were treated with monotherapy of weekly subcutaneous injections of abatacept 125 mg/mL. Time-to-treatment failure was evaluated as a primary outcome. The secondary objective was to evaluate the utility of different outcome measures to monitor disease activity. Safety was evaluated by adverse event reporting and serial blood analyses.

RESULTS

At the year-1 endpoint, there was significant improvement in vitreous haze grade (p=0.0014), central choroidal thickness (CCT) (p=0.0011), Fluorescein Angiography (FA) Score (p=0.0014), Indocyanine Green Angiography (ICGA) Score (p<0.001) and total dual FA-ICGA Score (p<0.001). Best corrected visual acuity (BCVA) (p=0.8354) and central retinal thickness (CRT) (p=0.3549) did not change significantly. There were no serious adverse events reported. In total, 4 out of 15 patients left the trial during year 1 of whom 2 experienced treatment failure.

CONCLUSIONS

Abatacept is very efficacious to treat both retinal vasculitis and choroiditis in patients with BU and is well tolerated. BCVA and CRT are inadequate to monitor disease activity. On the other hand, CCT is a promising non-invasive tool to detect treatment response in early active BU and dual FA-ICGA Score is very helpful to evaluate retinal vasculitis and choroiditis quantitatively.

TRIAL REGISTRATION NUMBER

NCT03871361.

Treatment of non-infectious retinal vasculitis

Retinal vasculitis (RV) refers to an entity in which the retinal vasculature is inflamed, frequently with indications of inflammation elsewhere in the eye. Non-infectious RV can be idiopathic or associated with systemic disease, ocular conditions, and malignancy. It can also be classified based on the vessel affected: artery, vein, or both. Due to the lack of strong evidence-based treatment trials and algorithms for RV, physicians must often rely on their experience, which creates great variability in treating this entity. This article provides an overview of various treatment modalities used in the management of non-infectious RV, with a focus on immunomodulatory therapies. We outline a potential stepwise approach of starting with steroids to control the acute inflammation and subsequently changing to immunomodulatory therapy (IMT) for long-term treatment.

Birdshot Chorioretinopathy: A Review

Birdshot chorioretinopathy (BSCR) is a bilateral chronic inflammation of the eye with no extraocular manifestations. BSCR affects middle-aged individuals from European descent and is strongly associated with the human leucocyte antigen (HLA)-A29 allele. The immune mechanisms involved are not fully understood, but recent advances have shown the role of Endoplasmic Reticulum Aminopeptidase 2 (ERAP2) in disease pathogenesis. Multimodal imaging, including fluorescein angiography, indocyanine angiography, fundus autofluorescence, and optical coherence tomography, are useful in confirming the diagnosis and monitoring disease activity. Visual field testing is also important to assess the disease progression. To date, there is no consensus for optimal treatment regimen and duration. Local and systemic corticosteroids can be used for short periods, but immunosuppressive or biological therapies are usually needed for the long-term management of the disease. Here, we will review publications focused on birdshot chorioretinopathy to give an update on the pathophysiology, the multimodal imaging, and the treatment of the disease.

Birdshot Chorioretinopathy: Resistant versus Responsive

PURPOSE

To search findings that can explain the heterogeneity between Resistant and Responsive patients with birdshot chorioretinopathy.

PATIENTS AND METHODS

This was a retrospective observational case series on "Responsive" versus "Resistant" birdshot chorioretinopathy.

RESULTS

One-hundred-eighty and Ninety-nine patients were included in the Responsive and Resistant groups respectively. Multivariate analysis of paraclinical variables at the first visit demonstrated that mean deviation (p = .04), pattern standard deviation (p < .001), optic nerve head leakage (p = .012), large vessel leakage and staining (p = .01), and macular small vessel leakage (p = .03) were statistically significantly different between the two groups; however, at the visit preceding successful therapy, only macular small vessel leakage (p = .01) was statistically significantly different between the two groups.

CONCLUSION

.Small vessel leakage in the macular area and/or optic nerve head leakage at the earliest visit might be risk factors for resistant birdshot chorioretinopathy.

Mechanisms, Pathophysiology and Current Immunomodulatory/Immunosuppressive Therapy of Non-Infectious and/or Immune-Mediated Choroiditis

Non-infectious choroiditis comprises immune-mediated diseases resulting from diverse pathophysiological mechanisms. These conditions are sub-divided into two main groups, (1) diseases of the choriocapillaris and (2) diseases of the choroidal stroma. The purpose of this study is to expose the pathophysiology of the most common diseases of both these groups and recommend the optimal immunomodulatory/immunosuppressive therapy of each analyzed condition based on literature data and data from our own centers. Material and Methods: Narrative review. In the group of choriocapillaritis entities or primary inflammatory choriocapillaropathies (PICCPs) including multiple evanescent white dot syndrome (MEWDS), acute posterior multifocal placoid pigment epitheliopathy (APMPPE), idiopathic multifocal choroiditis (MFC) and serpiginous choroiditis (SC), as well as secondary choriocapillaritides including acute syphilitic posterior multifocal placoid chorioretinitis (ASPMPC) and tuberculosis-related SC (TB-SC), were analyzed. In the group of stromal choroidites, HLA-A29 birdshot retinochoroiditis (BRC) and Vogt-Koyanagi-Harada (VKH) disease were included. For each entity a literature search, in the PubMed database, on treatment was performed and analyzed and the therapeutic attitudes of our own centers were presented. Management of immune-mediated choroiditis implies vigorous immunosuppressive therapy given in a prompt and prolonged fashion in most of these entities.

Long-term outcomes of systemic corticosteroid-sparing immunomodulatory therapy for Birdshot Retinochoroidopathy

PURPOSE

To report the visual prognosis, electroretinography (ERG) and perimetry outcomes of systemic corticosteroid-sparing immunomodulatory treatment (IMT) for birdshot retinochoroidopathy (BSRC).

METHODS

Retrospective non-comparative case series of 132 patients (264 eyes) with BSRC treated with IMT from Massachusetts Eye Research and Surgery Institution.

RESULTS

The average follow-up time was 60.1 months. After one year on IMT, 39.4% showed no clinically active inflammation. After 5 years of IMT, 78.0% had no signs of clinical inflammation. No significant differences were observed on best-corrected visual acuity (BCVA), ERG parameters, and perimetry parameters between baseline and subsequent visits on IMT.

CONCLUSION

Long-term systemic corticosteroid-sparing IMT was associated with a low rate of BSRC disease exacerbation. While differences were seen on testing parameters, they were not consistent trends and difference were attributed to variability of testing or fluctuation of inflammation that may be expected in the course of the disease.

New therapies in development for the management of non-infectious uveitis: A review

Uveitis is a spectrum of inflammatory disorders characterized by ocular inflammation and is one of the leading causes of preventable visual loss. The main aim of the treatment of uveitis is to control the inflammation, prevent recurrences of the disease and preserve vision while minimizing the adverse effects associated with the therapeutic agents. Initial management of uveitis relies heavily on the use of corticosteroids. However, monotherapy with high-dose corticosteroids is associated with side effects and cannot be maintained long term. Therefore, steroid-sparing agents are needed to decrease the burden of steroid therapy. Currently, the therapeutic approach for non-infectious uveitis (NIU) consists of a step-ladder strategy with the first-line option being corticosteroids in various formulations followed by the use of first-, second- and third-line agents in cases with suboptimal steroid response. Unfortunately, the agents currently at our disposal have limitations such as having a narrow therapeutic window along with their own individual potential side-effect profiles. Therefore, research has been targeted to identify newer drugs as well as new uses for older drugs that target specific pathways in the inflammatory response. Such efforts are made in order to provide targeted and safer therapy with reduced side effects and greater efficacy. Several specially designed molecular antibodies are currently in various phases of investigations that can potentially halt the inflammation in patients with NIU. In the review, we have provided a comprehensive overview of the current and upcoming therapeutic options for patients with NIU.

Biologics for the treatment of noninfectious uveitis: current concepts and emerging therapeutics

PURPOSE OF REVIEW

There is mounting evidence supporting the use of biologic therapeutics for the management of noninfectious uveitis (NIU). This review highlights: biologics with documented efficacy in NIU; agents with ongoing evaluation for efficacy in uveitis; and therapeutics for which investigation for efficacy in NIU is warranted.

RECENT FINDINGS

The tumor necrosis factor-alpha (TNF-α) inhibitor adalimumab has recently gained approval by the Food and Drug Administration for the treatment of noninfectious intermediate, posterior, and panuveitis. There is mounting evidence supporting the use of tocilizumab and rituximab in NIU. There is developing interest in evaluating the interleukin (IL)-23 inhibitors for efficacy in NIU.

SUMMARY

The TNF-α inhibitors adalimumab and infliximab have the greatest body of data supporting their use in NIU. These agents are considered second-line therapy for most forms of NIU but may be considered first-line therapy for uveitis associated with Behçet's disease and juvenile idiopathic arthritis. The B-cell inhibitor rituximab and the IL-6 inhibitor tocilizumab also have documented efficacy in NIU. Tocilizumab and interferon therapy may be particularly efficacious in the management of uveitic macular edema. The IL-23 inhibitors and janus kinase inhibitors are agents whose efficacy in NIU will likely be determined in the near future.

Update in treatment of uveitic macular edema

Macular edema (ME) represents the most common cause for visual loss among uveitis patients. The management of uveitic macular edema (UME) may be challenging, due to its often recalcitrant nature. Corticosteroids remain the mainstay of treatment, through their capability of effectively controlling inflammation and the associated ME. Topical steroids may be effective in milder cases of UME, particularly in edema associated with anterior uveitis. Posterior sub-Tenon and orbital floor steroids, as well as intravitreal steroids often induce rapid regression of UME, although this may be followed by recurrence of the pathology. Intra-vitreal corticosteroid implants provide sustained release of steroids facilitating regression of ME with less frequent injections. Topical nonsteroidal anti-inflammatory drugs may provide a safe alternative or adjuvant therapy to topical steroids in mild UME, predominantly in cases with underlying anterior uveitis. Immunomodulators including methotrexate, mycophenolate mofetil, tacrolimus, azathioprine, and cyclosporine, as well as biologic agents, notably the anti-tumor necrosis factor-α monoclonal antibodies adalimumab and infliximab, may accomplish the control of inflammation and associated ME in refractory cases, or enable the tapering of steroids. Newer biotherapies have demonstrated promising outcomes and may be considered in persisting cases of UME.

Safety profile and efficacy of tacrolimus in the treatment of birdshot retinochoroiditis: a retrospective case series review

AIM

Evaluation of the use of tacrolimus in the treatment of birdshot retinochoroiditis (BRC) at a tertiary referral centre with the aim to describe its safety and efficacy.

METHODS

The medical records of 25 patients diagnosed with BRC at uveitis service, Moorfields Eye Hospital, and who had received tacrolimus treatment were retrospectively reviewed. The main outcome measures of the study were (1) safety of tacrolimus in terms of side effects and (2) efficacy, as measured both by control of inflammation and visual function assessed by Humphrey visual fields and electrophysiological testing over at least 6 months and then 1 year.

RESULTS

Tacrolimus was commenced in 25 patients (mean age 50.4±10.8 years) and was well tolerated in 21 patients (84%). It was necessary to stop the tacrolimus in four patients. No patient showed major changes in renal function: 3/21 patients (14.28%) showed slightly abnormal (less than 30%) function at the end of the first month of treatment; 1/21 (4.76%) patients at 3 months, but at the end of a 6-month treatment period only 1/21 patients (4.76%) showed minor abnormality in renal function. The mean daily prednisolone dose was 19.7 mg at the beginning of the study, which had fallen to 6.9 mg at the end (t=5.071, p=0.001). Visual acuity mostly remained stable. Visual fields improved over time (mean improvement in Humphrey mean deviation, right eye=1.8±2.4 dB, t=3.821, p=0.004; left eye=1.9±2.7, dB, t=3.06, p=0.007). Electrophysiological function showed improvement in 10 patients, and in four patients an initial deterioration in function improved following tacrolimus dose adjustment.

CONCLUSION

Tacrolimus has a good safety profile for long-term use in patients with BRC as a second-line agent enabling steroid sparing and visual function stabilisation or improvement.

Adalimumab in refractory cystoid macular edema associated with birdshot chorioretinopathy

PURPOSE

To report the clinical outcomes of adalimumab therapy in cases of birdshot chorioretinitis (BCR) with cystoid macular edema (CME) refractory to conventional immunotherapy.

METHODS

This is a retrospective case series of three BCR patients treated with adalimumab for refractory CME. The main outcome measure was central subfield thickness (CST) on optical coherence tomography. Any patients treated with local steroids and/or receiving systemic steroids higher than 40 mg prednisolone daily during adalimumab therapy were excluded.

RESULTS

At baseline, all patients were receiving systemic corticosteroids and two second-line immunosuppressive agents. The mean duration of treatment with adalimumab was 31.2 months (range 17.2-52). The mean CST was 327 ± 112.7 μm (mean ± SD) at baseline and 256.2 ± 39.7 μm at 6 months and 235.5 ± 32.5 μm at 12 months. Adalimumab permitted cessation or reduction in the daily dose of oral prednisolone plus withdrawal of a second-line agent in all patients.

CONCLUSIONS

In these patients, adalimumab was effective in the treatment of refractory CME.

Interferon-alpha2a and Systemic Corticosteroid in Monotherapy in Chronic Uveitis: Results of the Randomized Controlled BIRDFERON Study

PURPOSE

Macular edema is the leading cause of vision loss in bilateral chronic noninfectious posterior uveitis, and is currently being treated using corticosteroids, immunosuppressive agents, and biotherapies. The aim of this trial was to assess and compare the efficacy and safety of corticosteroids and interferon-α (IFN-α) in adults with such conditions.

DESIGN

Randomized controlled trial.

METHODS

Subjects: Adult patients with bilateral posterior autoimmune noninfectious and nontumoral uveitis complicated by macular edema in at least 1 eye.

INTERVENTION

Patients received either subcutaneous IFN-α2a, systemic corticosteroids, or no treatment for 4 months. The efficacy and safety were assessed for up to 4 months.

MAIN OUTCOME MEASURES

The main endpoint was the change of the central foveal thickness (CFT) obtained by optical coherence tomography.

RESULTS

Forty-eight patients were included. In intention-to-treat analysis, the median CFT change showed no significant difference. However, the per-protocol analysis showed a significant difference between groups for both eyes (OD and OS), and for the worse and better eyes. Statistically significant difference was found between the control and corticosteroid groups for the OD (P = .0285), and between the control and IFN-α groups for the OD (P = .0424) and worse eye (P = .0354). Serious adverse events occurred in 2 patients in the IFN group, in 1 patient in the corticosteroid group, and in 2 patients in the control group and were completely resolved after switch.

CONCLUSIONS

IFN-α and systemic corticosteroids, compared with no treatment, were associated with significant anatomic and visual improvement shown in the per-protocol study.

Uveitic macular edema

Macular edema (ME) may complicate anterior, intermediate, and posterior uveitis, which may be because of various infectious, neoplastic or autoimmune etiologies. BRB breakdown is involved in the pathogenesis of Uveitic ME (UME). Optical coherence tomography has become a standard tool to confirm the diagnosis of macular thickening, due to its non-invasive, reproducible, and sensitive features. Retinal fluorescein and indocyanine green angiography is helpful to study the macula and screen for associated vasculitis, detect ischemic areas and preretinal, prepapillary or choroidal neovascular complications, and it may provide information about the etiology and be needed to assess the therapeutic response. UME due to an infection or neoplastic infiltration may require a specific treatment. If it remains persistent or occurs in other etiologies, immunomodulatory treatments may be needed. Intravitreal, subconjunctival, or subtenon corticosteroids are widely used. Their local use is contraindicated in glaucoma patients and limited by their short-lasting action. In case of bilateral sight-threatening chronic posterior uveitis, systemic treatments are usually needed, and corticosteroids are used as the standard first-line therapy. In order to reduce the daily steroid dose, immunosuppressive or immunomodulatory agents may be added, some of them being now available intravitreally. Ongoing prospective studies are assessing biotherapies and immunomodulators to determine their safety and efficacy in this indication.

Birdshot chorioretinopathy: current knowledge and new concepts in pathophysiology, diagnosis, monitoring and treatment

Birdshot chorioretinopathy (BCR) is a rare form of chronic, bilateral, posterior uveitis with a distinctive clinical phenotype, and a strong association with HLA-A29. It predominantly affects people in middle age. Given its rarity, patients often encounter delays in diagnosis leading to delays in adequate treatment, and thus risking significant visual loss. Recent advances have helped increase our understanding of the underlying autoimmune mechanisms involved in disease pathogenesis, and new diagnostic approaches such as multimodality imaging have improved our ability to both diagnose and monitor disease activity. Whilst traditional immunosuppressants may be effective in BCR, increased understanding of immune pathways is enabling development of newer treatment modalities, offering the potential for targeted modulation of immune mediators. In this review, we will discuss current understanding of BCR and explore recent developments in diagnosis, monitoring and treatment of this disease. Synonyms for BCR: Birdshot chorioretinopathy, Birdshot retinochoroiditis, Birdshot retino-choroidopathy, Vitiliginous choroiditis. Orphanet number: ORPHA179 OMIM: 605808.

Progress in the understanding and utilization of biologic response modifiers in the treatment of uveitis

Uveitis is the third most common cause of blindness in developed countries. Considering the systemic and local complications of long-term corticosteroid therapy and the intolerance due to side effects and ineffectiveness of conventional chemotherapy, use of biologic response modifiers is a reasonable alternative in the treatment of non-infectious uveitis and persistent uveitic macular edema. The majority of the evidence presented here comes from open uncontrolled analyses. Based on these studies, tumor necrosis factor alpha inhibitors, especially infliximab and adalimumab, have been shown to be effective in the treatment of non-infectious uveitis in numerous studies. More research is necessary, particularly multi-center randomized clinical trials, to address the choice of biologic response modifier agent and the length of treatment as we employ biologic response modifiers in different types of uveitis and persistent uveitic macular edema.

Visual Electrodiagnostic Testing in Birdshot Chorioretinopathy

Birdshot chorioretinopathy (BSCR) is a rare form of autoimmune posterior uveitis that can affect the visual function and, if left untreated, can lead to sight-threatening complications and loss of central vision. We performed a systematic search of the literature focused on visual electrophysiology studies, including electroretinography (ERG), electrooculography (EOG), and visual evoked potentials (VEP), used to monitor the progression of BSCR and estimate treatment efficacy. Many reports were identified, including using a variety of methodologies and patient populations, which makes a direct comparison of the results difficult, especially with some of the earlier studies using nonstandardized methodology. Several different electrophysiological parameters, like EOG Arden's ratio and the multifocal ERG response densities, are reported to be widely affected. However, informal consensus emerged in the past decade that the full-field ERG light-adapted 30 Hz flicker peak time is one of the most sensitive electrophysiological parameters. As such, it has been used widely in clinical trials to evaluate drug safety and efficacy and to guide therapeutic decisions in clinical practice. Despite its wide use, a well-designed longitudinal multicenter study to systematically evaluate and compare different electrophysiological methods or parameters in BSCR is still lacking but would benefit both diagnostic and therapeutic decisions.

Safety and efficacy of fluocinolone acetonide intravitreal implant (0.59 mg) in birdshot retinochoroidopathy

PURPOSE

To report the treatment outcomes of the fluocinolone acetonide intravitreal implant (0.59 mg) in patients with birdshot retinochoroidopathy whose disease is refractory or intolerant to conventional immunomodulatory therapy.

METHODS

A retrospective case series involving 11 birdshot retinochoroidopathy patients (11 eyes). Eleven patients (11 eyes) underwent surgery for fluocinolone acetonide implant (0.59 mg). Treatment outcomes of interest were noted at baseline, before fluocinolone acetonide implant, and then at 6 months, 1 year, 2 years, 3 years, and beyond 3 years. Disease activity markers, including signs of ocular inflammation, evidence of retinal vasculitis, Swedish interactive threshold algorithm-short wavelength automated perimetry Humphrey visual field analysis, electroretinographic parameters, and optical coherence tomography were recorded. Data on occurrence of cataract and raised intraocular pressure were collected in all eyes.

RESULTS

Intraocular inflammation was present in 54.5, 9.9, 11.1, and 0% of patients at baseline, 6 months, 1 year, 2 years, 3 years, and beyond 3 years after receiving the implant, respectively. Active vasculitis was noted in 36.3% patients at baseline and 0% at 3 years of follow-up. More than 20% (47.61-67.2%) reduction in central retinal thickness was noted in all patients with cystoid macular edema at 6 months, 1 year, 2 years, and 3 years postimplant. At baseline, 54.5% patients were on immunomodulatory agents. This percentage decreased to 45.45, 44.4, and 14.28% at 1 year, 2 years, and 3 years postimplant, respectively. Adverse events included increased intraocular pressure (54.5%) and cataract formation (100%).

CONCLUSION

The data suggest that fluocinolone acetonide implant (0.59 mg) helps to control inflammation in otherwise treatment-refractory cases of birdshot retinochoroidopathy. It is associated with significant side effects of cataract and ocular hypertension requiring treatment.

Birdshot retinochoroidopathy

Birdshot retinochoroidopathy (BSRC) is an uncommon, but well-characterized chronic, bilateral posterior uveitis, which is uniquely associated with the human leukocyte antigen-A29 phenotype. The disease presents predominantly in middle-aged Caucasian females who complain of blurred vision, floaters, photopsias, paracentral scotomas and nyctalopia. While autoimmune mechanisms are thought to play an important role in the pathogenesis of BSRC, its etiology remains unknown. Important questions remain in our understanding of BSRC with respect to its pathogenesis, epidemiology, optimal treatment, and prognosis, including the determinants of remission and relapse, as well as the best strategy for monitoring disease activity, progression and response to therapy with electroretinographic and psychophysical testing, established and emerging imaging modalities, and peripheral cytokines profiles.

Birdshot chorioretinopathy

PURPOSE OF REVIEW

Birdshot chorioretinopathy remains incompletely understood, but new insights into its pathogenesis have been reported recently, and treatment and monitoring options have also expanded. Central visual acuity may remain good until the late stages of the disease, but loss of visual field and peripheral retinal function is common.

RECENT FINDINGS

The underlying pathogenesis of the disease has long been believed to be T-cell driven, but examination of the IL-17 pathway has now further refined the potential underlying mechanism. New imaging techniques, including extended depth imaging of the choroid with optical coherence tomography, have demonstrated promise in detecting disease activity earlier, enabling targeted treatment to be given. Treatment options have expanded with the advent of the biological agents, and these may yet improve outcomes, particularly in refractory patients.

SUMMARY

Laboratory research continues to investigate the underlying mechanisms of disease, but our understanding remains frustratingly incomplete for a disease with such a clear HLA association. Clinical research is increasingly being driven to improve the phenotyping of affected patients so that those at risk of visual loss can be identified early and treated more aggressively with individually targeted therapies such as the newer biological agents, but how successful this approach will ultimately prove to be remains to be seen.

Pharmacotherapy for uveitis: current management and emerging therapy

Uveitis, a group of conditions characterized by intraocular inflammation, is a major cause of sight loss in the working population. Most uveitis seen in Western countries is noninfectious and appears to be autoimmune or autoinflammatory in nature, requiring treatment with immunosuppressive and/or anti-inflammatory drugs. In this educational review, we outline the ideal characteristics of drugs for uveitis and review the data to support the use of current and emerging therapies in this context. It is crucial that we continue to develop new therapies for use in uveitis that aim to suppress disease activity, prevent accumulation of damage, and preserve visual function for patients with the minimum possible side effects.

A comprehensive review and update on the biologic treatment of adult noninfectious uveitis: part II

INTRODUCTION

Treatment of adult, noninfectious uveitis remains a major challenge for ophthalmologists around the world, especially in regard to recalcitrant cases. It is reported to comprise approximately 10% of preventable blindness in the USA. The cause of uveitis can be idiopathic or associated with infectious and systemic disorders. The era of biologic medical therapies provides new options for patients with otherwise treatment-resistant inflammatory eye disease.

AREAS COVERED

This two-part review gives a comprehensive overview of the existing medical treatment options for patients with adult, noninfectious uveitis, as well as important advances for the treatment ocular inflammation. Part I covers classic immunomodulation and latest information on corticosteroid therapy. In part II, emerging therapies are discussed, including biologic response modifiers, experimental treatments and ongoing clinical studies for uveitis.

EXPERT OPINION

The hazard of chronic corticosteroid use in the treatment of adult, noninfectious uveitis is well documented. Corticosteroid-sparing therapies, which offer a very favorable risk-benefit profile when administered properly, should be substituted. Although nothing is currently approved for on-label use in this indication, many therapies, through either translation or novel basic science research, have the potential to fill the currently exposed gaps.

Review of Systemic Immunosuppression for Autoimmune Uveitis

The purpose of this review is to comprehensively examine the various therapeutic agents available to treat autoimmune eye disease, their indications, clinical safety and recent developments. The stepladder approach is reviewed, including corticosteroid administration of various forms, classic immunomodulators, and newer biologic response modifiers. The authors present that corticosteroid monotherapy is almost never curative and carries significant side effects, while immunomodulatory therapy, when used appropriately as way to induce steroid-free remission, carries far less risk of causing long-term complications and provides greater potential of altering the immune system to induce a durable remission.

Update on the use of systemic biologic agents in the treatment of noninfectious uveitis

Uveitis is one of the leading causes of blindness worldwide. Noninfectious uveitis may be associated with other systemic conditions, such as human leukocyte antigen B27-related spondyloarthropathies, inflammatory bowel disease, juvenile idiopathic arthritis, Behçet’s disease, and sarcoidosis. Conventional therapy with corticosteroids and immunosuppressive agents (such as methotrexate, azathioprine, mycophenolate mofetil, and cyclosporine) may not be sufficient to control ocular inflammation or prevent non-ophthalmic complications in refractory patients. Off-label use of biologic response modifiers has been studied as primary and secondary therapeutic agents. They are very useful when conventional immunosuppressive therapy has failed or has been poorly tolerated, or to treat concomitant ophthalmic and systemic inflammation that might benefit from these medications. Biologic therapy, primarily infliximab, and adalimumab, have been shown to be rapidly effective for the treatment of various subtypes of refractory uveitis and retinal vasculitis, especially Behçet’s disease-related eye conditions and the uveitis associated with juvenile idiopathic arthritis. Other agents such as golimumab, abatacept, canakinumab, gevokizumab, tocilizumab, and alemtuzumab may have great future promise for the treatment of uveitis. It has been shown that with proper monitoring, biologic therapy can significantly improve quality of life in patients with uveitis, particularly those with concurrent systemic symptoms. However, given high cost as well as the limited long-term safety data, we do not routinely recommend biologics as first-line therapy for noninfectious uveitis in most patients. These agents should be used with caution by experienced clinicians. The present work aims to provide a broad and updated review of the current and in-development systemic biologic agents for the treatment of noninfectious uveitis.

Detection of choroid- and retina-antigen reactive CD8(+) and CD4(+) T lymphocytes in the vitreous fluid of patients with birdshot chorioretinopathy

Birdshot chorioretinopathy (BSCR), a progressive form of non-infectious uveitis, is the strongest HLA-associated disease described to date, with >95% of the patients displaying HLA-A29. Since indirect evidence indicates the involvement of T cells in the etiopathology of the disease, we now isolated, cultured and analyzed the vitreous fluid-infiltrating T cells from two BSCR patients with respect to their phenotype, cytokine profile, clonal distribution and antigen specificity. Phenotypic analyses revealed the predominant presence of both CD4(+) and CD8(+) T cells in vitreous fluid. Further analyses on short term expanded and cloned T cells suggested that eye-infiltrating T cells generally displayed a Th1 like cytokine profile with secretion of high levels of IFN-γ and TNF-α. In one patient an oligoclonal CD4(+) and CD8(+) T cell infiltration, with a moderate to strongly skewed TCR Vβ usage was suggestive for an antigen driven infiltration/expansion. Indeed, a number of intraocular CD4(+) and CD8(+) T cells responded to crude retinal and choroidal lysates. These results, which demonstrate for the first time the existence of eye-antigen-specific T cells in the vitreous fluid of BSCR patients, substantiate the current view on the role of eye-antigen specific T cells in the etiopathology of BSCR.

Birdshot uveitis: current and emerging treatment options

Birdshot chorioretinopathy is a relatively uncommon subtype of idiopathic posterior uveitis with distinct clinical characteristics and a strong genetic association with the Human Leukocyte Antigen (HLA)-A29 allele. The diagnosis remains clinical and is based on the presence of typical clinical features, including multiple, distinctive, hypopigmented choroidal lesions throughout the fundus. The long-term visual prognosis of this disorder, however, remains guarded – central visual acuity can be preserved until late in the disease and it is not uncommon for patients to receive inadequate immunosuppressive treatment, leading to a poor long-term outcome in which peripheral retinal damage eventually leads to visual deterioration. Birdshot chorioretinopathy has proven a particularly attractive area of study within the field of uveitis, as it is a relatively easily defined disease with an associated human leukocyte antigen haplotype. Despite this, however, the immune mechanisms involved in its pathogenesis remain unclear, and some patients continue to lose retinal function despite therapy with corticosteroids and conventional immunosuppressive agents. Laboratory research continues to investigate the underlying mechanisms of disease, and clinical research is now being driven to improve the phenotyping and monitoring of this condition as, in the era of so-called personalized medicine, it is becoming increasingly important to identify patients at risk of visual loss early so that they can be treated more aggressively with targeted therapies such as the newer biological agents. This approach requires the formation of collaborative groups, as the relative rarity of the condition makes it difficult for one center to accumulate enough patients for worthwhile studies. Nevertheless, results obtained with newer therapies, such as biological agents directed against particular cytokines or cell-surface receptors, demonstrate ever improving control of the inflammation in refractory cases, providing hope that the outlook for visual function in this condition can only improve.

Systemic treatments for noninfectious vitreous inflammation

Vitreous inflammation, or vitritis, may result from many causes, including both infectious and noninfectious, including rheumatologic and autoimmune processes. Vitritis is commonly vision threatening and has serious sequelae. Treatment is frequently challenging, but, today, there are multiple methods of systemic treatment for vitritis. These categories include corticosteroids, antimetabolites, alkylating agents, T-cell inhibitors/calcineurin inhibitors, and biologic agents. These treatment categories were reviewed last year, but, even over the course of just a year, many therapies have made progress, as we have learned more about their indications and efficacy. We discuss here discoveries made over the past year on both existing and new drugs, as well as reviewing mechanisms of action, clinical dosages, specific conditions that are treated, adverse effects, and usual course of treatment for each class of therapy.

Interleukin 21, interleukin 23, and transforming growth factor β1 in HLA-A29-associated birdshot retinochoroidopathy

PURPOSE

To determine the peripheral levels of 20 immune mediators in serum samples from patients with birdshot retinochoroidopathy (BSRC).

DESIGN

Single-center prospective case-control study.

METHODS

The serum of 17 BSRC patients during different phases of disease activity and therapy were analyzed with a quantitative multiplex sandwich enzyme-linked immunosorbent assay-based microarray to determine the levels of 20 immune mediators (T cell and proinflammatory). The serum of 12 healthy volunteers was used as controls.

RESULTS

Serum levels of interleukin (IL)-21 (P = .0005), IL-23 (P = .0005), and transforming growth factor (TGF)-β1 (P = .0011) were elevated in BSRC patients with active disease naïve to systemic therapy compared with that of controls. There was no significant difference in the serum levels of immune mediators between controls and BSRC patients who had a current or past history of IMT or who were in remission. The levels of IL-21, IL-23, and TGF-β1 were positively correlated (IL-23/IL-21, r = 0.91; TGF-β1/IL-21, r = 0.97; TGF-β1/IL-23, r = 0.87; for all, P < .0001).

CONCLUSIONS

BSRC patients with active disease naïve to systemic therapy have elevated serum levels of 3 key immune mediators known to promote T helper 17 (Th17) cells in autoimmune disease. Our results suggest that IL-21, IL-23, and TGF-β1 may play an important role in the development of site-specific Th17 cell-mediated inflammation in BSRC, which underscore the importance of systemic therapy and offer new insights into the potential of targeted treatments.

Treatment of cystoid macular edema in a patient with birdshot chorioretinopathy with bevacizumab

PURPOSE

Birdshot chorioretinopathy is currently treated with either systemic immune modulation or intravitreal polytherapy. These regimens pose challenges to the clinician and patient such as adverse effects, chronic treatment and compliance, and failure of therapy. In a patient with birdshot chorioretinopathy and juxtaposed cystoid macular edema, the authors assessed the efficacy of bevacizumab for treatment after systemic therapy had failed.

METHODS

A 48-year-old woman was injected with intravitreal bevacizumab 10 times in her right eye with 4 weeks to 6 weeks intervening between injections. Improvement was monitored by best-corrected visual acuity and ocular coherence tomography.

RESULTS

Visual acuity improved from 20/200 to 20/30 in the right eye, and foveal thickness improved from 638 μm to 200 μm. Visible signs of macular edema and inflammation completely disappeared.

CONCLUSION

Bevacizumab monotherapy may improve visual acuity with resolution of macular edema in patients with birdshot chorioretinopathy that is refractory to traditional systemic therapy.

Systemic treatment of vitreous inflammation

Non infectious vitreous inflammation is often vision threatening and can be associated with potentially life-threatening systemic conditions. Treatment is often challenging as it involves systemic medications that can be associated with adverse effects. The classes of drugs are ever expanding and include corticosteroids, antimetabolites, alkylating agents, T-cell and calcineurin agents, biologic agents, and interferons. Each class of systemic therapy for non-infectious vitreous inflammation is reviewed. We discuss the mechanisms of action, usual clinical dosages, the specific conditions that are treated, the adverse effects, and usual course of treatment for each class of therapy.

Biological agents for the treatment of uveitis

INTRODUCTION

The conventional treatment of uveitis includes corticosteroids and immunosuppressive agents, which are highly efficacious, but can be associated with serious systemic side effects. Over the last two decades, advances in the understanding of the pathogenesis of inflammatory diseases, as well as improved biotechnology, have enabled selective targeting of the chemical mediators of diseases. Recently, a new class of drugs called biologics, that target the various mediators of the inflammation cascade, may potentially provide more effective and less toxic treatment.

AREAS COVERED

This article is a review and summary of the peer-reviewed evidence for biologic agents in the treatment of various forms of ocular inflammation and it focuses on the potential use of other biologic agents that have been tested in experimental autoimmune uveitis. Pubmed was used as our main tool for our literature search. Some additional references were taken from books written on the subject.

EXPERT OPINION

There are a wide variety of new and emerging biological agents currently being used in the treatment of uveitis which has expanded the therapeutic horizons far beyond previous limitations.

Road to remission: a comprehensive review of therapy in uveitis

INTRODUCTION

Although uveitis remains the third leading cause of preventable blindness in the US, the care and management of patients with uveitis and ocular inflammatory disease sit poised to make evolutionary if not revolutionary changes in the years ahead. This review serves to highlight important advances in the pharmacologic options available for the treatment of uveitis and ocular inflammation.

AREAS COVERED

Advances in steroid therapy (both topical and extended delivery), updates in the clinical safety of systemic immune modulation, and the emerging therapies for uveitis and ocular inflammatory disease are some of the areas covered in this review.

EXPERT OPINION

Corticosteroids have been the mainstay in the care of patients with ocular inflammatory disorders for many years. Indeed, some physicians still use only steroids for treating inflamed eyes. However, the mission is remission of all corticosteroids in order to prevent the complications associated with long-term corticosteroid use. The goal is to achieve quiescence through aggressive use of corticosteroids to extinguish the fire and then move along to achieve steroid-free remission through immunosuppressant agents.

Intraocular interleukin-17 and proinflammatory cytokines in HLA-A29-associated birdshot chorioretinopathy

PURPOSE

To determine the levels of 23 immune mediators in paired aqueous humor (AqH) and serum samples from patients with birdshot chorioretinopathy (BSCR).

DESIGN

Single-centre case-control study.

METHODS

A multiplex immunoassay was used to determine the levels of 23 immune mediators (T-cell, proinflammatory, and vascular-active mediators) in paired AqH and serum of 16 BSCR patients. The AqH of 11 age-related cataract controls served as controls.

RESULTS

AqH levels of the T-cell mediators interleukin (IL)-2 (P=.044) and IL-17 (P=.039) and proinflammatory mediators IL-1β (P=.032), IL-6 (P=.034), and tumor necrosis factor α (P=.041) were elevated compared with that of age-related cataract controls. The elevated intraocular levels of IL-1β, IL-17, and tumor necrosis factor α in BSCR samples were higher than their concurrent serum levels. A significant positive correlation of intraocular mediators was noted between IL-17 and both IL-2 (r=0.744; P<.0001) and IL-23 (r=0.921; P<.0001) and between IL-2 and IL-23 (r=0.776; P<.0001). AqH levels of vascular-active mediators were not distinct between the groups.

CONCLUSIONS

BSCR patients have elevated intraocular levels of proinflammatory and T cell-associated cytokines. Our results suggest the novel pathogenic concept that BSCR is an autoimmune inflammatory disease restricted to the eye and associated with elevated IL-17.

Long-term daclizumab therapy for the treatment of noninfectious ocular inflammatory disease

OBJECTIVE

Safety and efficacy of daclizumab during an 11-year period.

DESIGN

Structured, retrospective chart review.

PARTICIPANTS

Thirty-nine patients.

METHODS

Patients with chronic, noninfectious intermediate and/or posterior uveitis.

RESULTS

Thirty-nine patients (78 eyes) were treated for a mean of 40.3 months. Visual acuity improved by ≥2 lines in the better eye in 7 patients (18.4%) and worsened by 2 lines in 6 patients (15.8%) with a mean of 2.8 Snellen lines of vision lost per eye. Six eyes with vitreous cell less than grade 2 lost 2 lines of vision and 7 eyes with less than grade 2 vitreous cell improved 2 lines. Mean number of immunosuppressive medications per patient decreased from 1.89 medications/patient to 1.17 medications/patient. The average number of periocular injections per patient was 1.46 (range, 0-9). The mean number of flares was 2.05/patient (range, 0-12), with the rate being 0.62 flares per patient-year. Four patients developed cancer during the course of this study. Mean time to onset of malignancy was 26 months and the mean age in this group was 49 years.

CONCLUSIONS

Daclizumab demonstrated efficacy in the reduction of concomitant immunosuppressive medication, stabilization of visual acuity, and the prevention of uveitic flares in most cases. Dermatologic complications were the most frequently observed adverse event in our series. Four patients developed solid tumor malignancies during this 11-year period.

Emerging drugs for uveitis

INTRODUCTION

Uveitis is a challenging disease covering both infectious and noninfectious conditions. The current treatment strategies are hampered by the paucity of randomized controlled trials and trials comparing the efficacy of different agents.

AREAS COVERED

This review describes the current and future treatments of uveitis. A literature search was performed in PUBMED from 1965 to 2010 on drugs treating ocular inflammation with emphasis placed on more recent, larger studies. Readers should gain a basic understanding of current treatment strategies beginning with corticosteroids and transitioning to steroid sparing agents. Steroid sparing agents include antimetabolites such as methotrexate, azathioprine and mycophenolate mofetil; calcineurin inhibitors which include cyclosporine, tacrolimus; alkylating agents which include cyclophosphamide and chlorambucil; and biologics which include the TNF-α inhibitors infliximab, adalimumab and etanercept and daclizumab, IFN-α(2a) and rituximab.

EXPERT OPINION

Newer agents are typically formulated from existing drugs or developed based on new advances in immunology. Future treatment will require a better understanding of the mechanisms involved in autoimmune diseases and better delivery systems in order to provide targeted treatment with minimal side effects.

Anti-inflammatory treatment of uveitis with biologicals: new treatment options that reflect pathogenetic knowledge of the disease

BACKGROUND

Endogenous uveitis is a sight-threatening disease. In addition to corticosteroids, immunosuppressive agents are commonly used to treat patients with severe course. Immunosuppressive drugs act nonspecifically, rather than providing a specific interaction with the critical pathogenetic pathways of uveitis. Better knowledge of the basic mechanisms underlying uveitis and of the molecules that are important for regulating inflammation has helped to create new and more specific treatment approaches. Biological therapy for inflammatory diseases employs substances that interfere with specific molecules or pathways induced in the body during the inflammatory process.

METHODS

This review gives an overview on molecules that play a critical role in the pathogenetic process of uveitis, as has been observed in patients or the respective animal models, and summarizes the current experience with biologicals for the treatment of uveitis refractive to conventional immunosuppressives.

Current approach in the diagnosis and management of posterior uveitis

Posterior uveitic entities are varied entities that are infective or non-infective in etiology. They can affect the adjacent structures such as the retina, vitreous, optic nerve head and retinal blood vessels. Thorough clinical evaluation gives a clue to the diagnosis while ancillary investigations and laboratory tests assist in confirming the diagnosis. Newer evolving techniques in the investigations and management have increased the diagnostic yield. In case of diagnostic dilemma, intraocular fluid evaluation for polymerase chain testing for the genome and antibody testing against the causative agent provide greater diagnostic ability.

In vitro end points for the assessment of cellular immune response-modulating drugs

BACKGROUND

The concept of immunotoxicology and the development of a battery of immune-function assays to screen potential immunotoxic compounds have been increasingly used in the past. Immunotoxic outcome generally seems appropriate to evaluate the risk in drug development. Improving this approach is possible, by using methods now available, to study the effect of a chemical compound on the immune system.

OBJECTIVE

The goal of this review is to provide an overview of the current and recent methodologies for testing the immunological effect and immunotoxic risks in drug candidates.

METHODS

The methodological details here discussed include a synthetic description of the immunocompetent cells in cell-mediated immunity and the choice of the most appropriate assay (bioassays, immunoassays, molecular biology techniques, flow cytometry).

CONCLUSION

This review offers an assessment of in vitro models to study the toxic impact of (bio)pharmaceuticals on cellular immune system and aid drug scientists in understanding the significance and the methods to approach immunotoxicology.