intravitreal tumor necrosis factor inhibitors in the treatment of refractory diabetic macular edema: a pilot study from the Pan-American Collaborative Retina Study Group. Retina. 2011;31:298-303. [PMID: 21099452 DOI: 10.1097/iae.0b013e3181eac7a6]

Rationale of Basic and Cellular Mechanisms Considered in Updating the Staging System for Diabetic Retinal Disease

Purpose

Hyperglycemia is a major risk factor for early lesions of diabetic retinal disease (DRD). Updating the DRD staging system to incorporate relevant basic and cellular mechanisms pertinent to DRD is necessary to better address early disease, disease progression, the use of therapeutic interventions, and treatment effectiveness.

Design

We sought to review preclinical and clinical evidence on basic and cellular mechanisms potentially pertinent to DRD that might eventually be relevant to update the DRD staging system.

Participants

Not applicable.

Methods

The Basic and Cellular Mechanisms Working Group (BCM-WG) of the Mary Tyler Moore Vision Initiative carefully and extensively reviewed available preclinical and clinical evidence through multiple iterations and classified these.

Main Outcome Measures

Classification was made into evidence grids, level of supporting evidence, and anticipated future relevance to DRD.

Results

A total of 40 identified targets based on pathophysiology and other parameters for DRD were grouped into concepts or evaluated as specific candidates. VEGFA, peroxisome proliferator-activated receptor-alpha related pathways, plasma kallikrein, and angiopoietin 2 had strong agreement as promising for use as biomarkers in diagnostic, monitoring, predictive, prognostic, and pharmacodynamic responses as well as for susceptibility/risk biomarkers that could underlie new assessments and eventually be considered within an updated DRD staging system or treatment, based on the evidence and need for research that would fit within a 2-year timeline. The BCM-WG found there was strong reason also to pursue the following important concepts regarding scientific research of DRD acknowledging their regulation by hyperglycemia: inflammatory/cytokines, oxidative signaling, vasoprotection, neuroprotection, mitophagy, and nutrients/microbiome.

Conclusion

Promising targets that might eventually be considered within an updated DRD staging system or treatment were identified. Although the BCM-WG recognizes that at this stage little can be incorporated into a new DRD staging system, numerous potential targets and important concepts deserve continued support and research, as they may eventually serve as biomarkers and/or therapeutic targets with measurable benefits to patients with diabetes.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Elevated aqueous TNF-α levels are associated with more severe functional and anatomic findings in eyes with diabetic macular oedema

BACKGROUND

Intravitreal ranibizumab for diabetic macular oedema (DMO) has been recently shown to modulate levels of aqueous cytokines. This study investigates the associations between changes in aqueous cytokine levels following intravitreal ranibizumab therapy and the corresponding anatomical and functional changes in the eye.

METHODS

Twenty-five patients comprising 30 eyes diagnosed with DMO were prospectively recruited. All eyes received three loading dose ranibizumab injections at baseline, week 4 and week 8, followed by pro re nata treatment based on best-corrected visual acuity (BCVA) and central macular thickness (CMT) up to week 48. Prior to ranibizumab administration, aqueous samples were collected from all eyes, and subsequent sampling was performed at week 8. Levels of 32 cytokines were assessed at baseline and at week 8.

RESULTS

At baseline, higher aqueous TNF-α levels were associated with poorer BCVA (p = 0.033), greater macular volume (p = 0.017) and worse diabetic retinopathy (p = 0.047). Higher levels of IL-7 were associated with poorer BCVA and greater macular volume (MV). Following treatment with ranibizumab there was a significant correlation with reduction of aqueous TNF-α and improvements in BCVA and MV, both at 6 months (BCVA [r = -0.558, p = 0.001], MV [r = 0.410, p = 0.024]) and 12-months (BCVA [r = -0.413, p = 0.023], MV [r = 0.482, p = 0.008]). The change in VEGF concentration following ranibizumab treatment did not correlate with either BCVA or MV improvements (p > 0.05).

CONCLUSIONS

Higher levels of aqueous TNF-α and IL-7 correlated with worse DMO, both anatomically and functionally. Reductions in levels of aqueous TNF-α, but not VEGF, post ranibizumab treatment were associated with improvement in BCVA and MV.

Incidence of diabetic retinopathy in anti-tnf treated rheumatic disease patients with type 2 diabetes

OBJECTIVE

This study aimed to evaluate the impact of anti-TNF (biological) therapies on the incidence and progression of diabetic retinopathy.

MATERIALS AND METHODS

A cross-sectional analysis of 50 diabetic patients with rheumatic diseases (group 1) was performed. An age-, sex-, and HbA1c-matched control group (group 2) was formed from a pool of diabetic patients who underwent regular eye examinations. The presence or absence of diabetic retinopathy was also assessed. Comorbidities such as hypertension, coronary artery disease, and hyperlipidemia were also evaluated as possible confounding factors.

RESULTS

Hundred eyes of 50 patients were evaluated in each group. Only three patients in group 1 had non-proliferative retinopathy. The median duration of rheumatic disease was 9 years, whereas that of diabetes was 11 years. The mean duration of anti-TNF therapy was 4 years. In the control group of diabetes-only patients, 13 patients developed some form of newly diagnosed diabetic retinopathy during the last five years. The calculated retinopathy occurrence between the groups was statistically significant (p < 0.05). In this study, the incidence rate ratio for patients receiving anti-TNF treatment was calculated as 0.4 in the study.

CONCLUSION

TNF inhibitors, with their anti-inflammatory effects, positively impact diabetic complications by reducing the incidence of retinopathy. To our knowledge, this is the first study to evaluate retinopathy development after anti-TNF therapy.

Inflammatory cytokines as mediators of retinal endothelial barrier dysfunction in non-infectious uveitis

Characterised by intraocular inflammation, non-infectious uveitis includes a large group of autoimmune and autoinflammatory diseases that either involve the eye alone or have both ocular and systemic manifestations. When non-infectious uveitis involves the posterior segment of the eye, specifically the retina, there is substantial risk of vision loss, often linked to breakdown of the inner blood-retinal barrier. This barrier is formed by non-fenestrated retinal vascular endothelial cells, reinforced by supporting cells that include pericytes, Müller cells and astrocytes. Across the published literature, a group of inflammatory cytokines stand out as prominent mediators of intraocular inflammation, with effects on the retinal endothelium that may contribute to breakdown of the inner blood-retinal barrier, namely tumour necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-8, IL-17 and chemokine C-C motif ligand (CCL)2. This article reviews the function of each cytokine and discusses the evidence for their involvement in retinal endothelial barrier dysfunction in non-infectious uveitis, including basic laboratory investigations, studies of ocular fluids collected from patients with non-infectious uveitis, and results of clinical treatment trials. The review also outlines gaps in knowledge in this area. Understanding the disease processes at a molecular level can suggest treatment alternatives that are directed against appropriate biological targets to protect the posterior segment of eye and preserve vision in non-infectious uveitis.

Inflammation: The Link between Neural and Vascular Impairment in the Diabetic Retina and Therapeutic Implications

The etiology of diabetic retinopathy (DR) is complex, multifactorial and compromises all the elements of the retinal neurovascular unit (NVU). This diabetic complication has a chronic low-grade inflammatory component involving multiple inflammatory mediators and adhesion molecules. The diabetic milieu promotes reactive gliosis, pro-inflammatory cytokine production and leukocyte recruitment, which contribute to the disruption of the blood retinal barrier. The understanding and the continuous research of the mechanisms behind the strong inflammatory component of the disease allows the design of new therapeutic strategies to address this unmet medical need. In this context, the aim of this review article is to recapitulate the latest research on the role of inflammation in DR and to discuss the efficacy of currently administered anti-inflammatory treatments and those still under development.

Persistent diabetic macular edema: Definition, incidence, biomarkers, and treatment methods

Intravitreal antivascular endothelial growth factor (anti-VEGF) treatment has drastically improved the visual and anatomical outcomes in patients with diabetic macular edema (DME); however, success is not always guaranteed, and a proportion of these eyes demonstrate persistent DME (pDME) despite intensive treatment. While standardized criteria to define these treatment-resistant eyes have not yet been established, many studies refer to eyes with no clinical response or an unsatisfactory partial response as having pDME. A patient is considered to have pDME if the retinal thickness improves less than 10-25% after 6 months of treatment. A range of treatment options have been recommended for eyes with pDME, including switching anti-VEGF agents, using corticosteroids and/or antioxidant drugs in adjunct with anti-VEGF therapy, and vitrectomy. In addition, multimodal imaging of DME eyes may be advantageous in predicting the responsiveness to treatment; this is beneficial when initiating alternative therapies. We explore the literature on persistent DME regarding its defining criteria, incidence, the baseline biological markers that may be useful in anticipating the response to treatment, and the available treatment options.

Neuroinflammation and neurodegeneration in diabetic retinopathy

Diabetic retinopathy (DR) is the most common complication of diabetes and has been historically regarded as a microangiopathic disease. Now, the paradigm is shifting toward a more comprehensive view of diabetic retinal disease (DRD) as a tissue-specific neurovascular complication, in which persistently high glycemia causes not only microvascular damage and ischemia but also intraretinal inflammation and neuronal degeneration. Despite the increasing knowledge on the pathogenic pathways involved in DR, currently approved treatments are focused only on its late-stage vasculopathic complications, and a single molecular target, vascular endothelial growth factor (VEGF), has been extensively studied, leading to drug development and approval. In this review, we discuss the state of the art of research on neuroinflammation and neurodegeneration in diabetes, with a focus on pathophysiological studies on human subjects, in vivo imaging biomarkers, and clinical trials on novel therapeutic options.

A comprehensive review of intravitreal immunosuppressants and biologicals used in ophthalmology

Systemic immunosuppressants and biologicals have been a valuable tool in the treatment of inflammatory diseases and malignancies. The safety profile of these drugs has been debatable, especially in localized systems, such as the eye. This has led to the search for fairly local approaches, such as intravitreal, subconjunctival, and topical route of administration. Immunosuppressants have been used as a second-line drug in patients intolerable to corticosteroids or those who develop multiple recurrences on weaning corticosteroids. Similarly, biologicals have also been used as the next line of therapy, when adequate control of inflammation could not be attained or immunosuppressants were contraindicated to patients. Intravitreal immunosuppressants, such as methotrexate and sirolimus, have been extensively studied in noninfectious posterior uveitis, whereas limited studies have established the efficacy of intravitreal biologicals, such as infliximab and adalimumab. Most of these drugs have shown good safety profile and tolerability in animal studies alone and have not been studied further in human subjects. However, most of the studies in literature are single-case reports or case series which limits the level of evidence. In this comprehensive review, we discuss the mechanism of action, pharmacodynamics, pharmacokinetics, indications, efficacy, and side effects of different intravitreal immunosuppressants and biologicals that have been studied in literature.

Monoclonal antibodies in diabetic retinopathy

INTRODUCTION

Diabetic retinopathy (DR), as one of the main complications of diabetes, is among the leading causes of blindness and visual impairment worldwide.

AREAS COVERED

Current clinical therapies include photocoagulation, vitrectomy, and anti-vascular endothelial growth factor (VEGF) therapies. Bevacizumab and ranibizumab are two monoclonal antibodies (mAbs) inhibiting angiogenesis. Intravitreal ranibizumab and bevacizumab can decrease the rate of blindness and retinal thickness, and improve visual acuity whether as monotherapy or combined with other treatments. They can increase the efficacy of other treatments and decrease their adverse events. Although administered intravitreally, they also might enter the circulation and cause systemic effects. This study is aimed to review our current knowledge about mAbs, bevacizumab and ranibizumab, in DR including superiorities, challenges, and limitations. Meanwhile, we tried to shed light on new ideas to overcome these limitations. Our latest search was done in April 2021 mainly through PubMed and Google Scholar. Relevant clinical studies were imported.

EXPERT OPINION

Future direction includes detection of more therapeutic targets considering other components of DR pathophysiology and shared pathogenesis of DR and neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease, the treat-and-extend regimen, and new ways of drug delivery and other routes of ocular drug administration.

Neurovascular Impairment and Therapeutic Strategies in Diabetic Retinopathy

Diabetic retinopathy has recently been defined as a highly specific neurovascular complication of diabetes. The chronic progression of the impairment of the interdependence of neurovascular units (NVUs) is associated with the pathogenesis of diabetic retinopathy. The NVUs consist of neurons, glial cells, and vascular cells, and the interdependent relationships between these cells are disturbed under diabetic conditions. Clinicians should understand and update the current knowledge of the neurovascular impairments in diabetic retinopathy. Above all, neuronal cell death is an irreversible change, and it is directly related to vision loss in patients with diabetic retinopathy. Thus, neuroprotective and vasoprotective therapies for diabetic retinopathy must be established. Understanding the physiological and pathological interdependence of the NVUs is helpful in establishing neuroprotective and vasoprotective therapies for diabetic retinopathy. This review focuses on the pathogenesis of the neurovascular impairments and introduces possible neurovascular protective therapies for diabetic retinopathy.

The role of inflammation and neurodegeneration in diabetic macular edema

The pathogenesis of diabetic macular edema (DME) is complex. Persistently high blood glucose activates multiple cellular pathways and induces inflammation, oxidation stress, and vascular dysfunction. Retinal ganglion cells, macroglial and microglial cells, endothelial cells, pericytes, and retinal pigment epithelium cells are involved. Neurodegeneration, characterized by dysfunction or apoptotic loss of retinal neurons, occurs early and independently from the vascular alterations. Despite the increasing knowledge on the pathways involved in DME, only limited therapeutic strategies are available. Besides antiangiogenic drugs and intravitreal corticosteroids, alternative therapeutic options tackling inflammation, oxidative stress, and neurodegeneration have been considered, but none of them has been currently approved.

Recent Advancements in the Medical Treatment of Diabetic Retinal Disease

Diabetic retinal disease remains one of the most common complications of diabetes mellitus (DM) and a leading cause of preventable blindness. The mainstay of management involves glycemic control, intravitreal, and laser therapy. However, intravitreal therapy commonly requires frequent hospital visits and some patients fail to achieve a significant improvement in vision. Novel and long-acting therapies targeting a range of pathways are warranted, while evidence to support optimal combinations of treatments is currently insufficient. Improved understanding of the molecular pathways involved in pathogenesis is driving the development of therapeutic agents not only targeting visible microvascular disease and metabolic derangements, but also inflammation and accelerated retinal neurodegeneration. This review summarizes the current and emerging treatments of diabetic retinal diseases and provides an insight into the future of managing this important condition.

Neurovascular unit in diabetic retinopathy: pathophysiological roles and potential therapeutical targets

Diabetic retinopathy (DR), one of the common complications of diabetes, is the leading cause of visual loss in working-age individuals in many industrialized countries. It has been traditionally regarded as a purely microvascular disease in the retina. However, an increasing number of studies have shown that DR is a complex neurovascular disorder that affects not only vascular structure but also neural tissue of the retina. Deterioration of neural retina could precede microvascular abnormalities in the DR, leading to microvascular changes. Furthermore, disruption of interactions among neurons, vascular cells, glia and local immune cells, which collectively form the neurovascular unit, is considered to be associated with the progression of DR early on in the disease. Therefore, it makes sense to develop new therapeutic strategies to prevent or reverse retinal neurodegeneration, neuroinflammation and impaired cell-cell interactions of the neurovascular unit in early stage DR. Here, we present current perspectives on the pathophysiology of DR as a neurovascular disease, especially at the early stage. Potential novel treatments for preventing or reversing neurovascular injuries in DR are discussed as well.

Retinal Inflammation, Cell Death and Inherited Retinal Dystrophies

Inherited retinal dystrophies (IRDs) are a group of retinal disorders that cause progressive and severe loss of vision because of retinal cell death, mainly photoreceptor cells. IRDs include retinitis pigmentosa (RP), the most common IRD. IRDs present a genetic and clinical heterogeneity that makes it difficult to achieve proper treatment. The progression of IRDs is influenced, among other factors, by the activation of the immune cells (microglia, macrophages, etc.) and the release of inflammatory molecules such as chemokines and cytokines. Upregulation of tumor necrosis factor alpha (TNFα), a pro-inflammatory cytokine, is found in IRDs. This cytokine may influence photoreceptor cell death. Different cell death mechanisms are proposed, including apoptosis, necroptosis, pyroptosis, autophagy, excessive activation of calpains, or parthanatos for photoreceptor cell death. Some of these cell death mechanisms are linked to TNFα upregulation and inflammation. Therapeutic approaches that reduce retinal inflammation have emerged as useful therapies for slowing down the progression of IRDs. We focused this review on the relationship between retinal inflammation and the different cell death mechanisms involved in RP. We also reviewed the main anti-inflammatory therapies for the treatment of IRDs.

Efficacy and safety of immunomodulatory drugs in patients with non-infectious intermediate and posterior uveitis, panuveitis and macular edema: A systematic literature review

BACKGROUND

Non-infectious non-anterior uveitis (NINA) is a sight-threatening condition that often requires immunomodulatory drugs (IMDs) for its management.

OBJECTIVES

To evaluate the published evidence regarding the use of IMDs in adult patients with NINA uveitis including intermediate (IU) and posterior uveitis (PU), panuveitis (PanU) and macular edema (ME).

METHODS

We performed a systematic literature review. Search strategies were designed for Medline, Embase, and Cochrane Libraries for articles up to 2019 to evaluate the efficacy and safety of the IMDs. A quality assessment was performed using the Jadad Scale.

RESULTS

Nineteen randomized clinical trials were selected from the 1,103 articles retrieved. Characteristics of patients, treatment dosages and outcome measures were heterogeneous. The outcomes most frequently analyzed were visual acuity (VA), macular thickness and vitreous haze (VH). Different IMDs were used at their usual dosages. Methotrexate (MTX), micophenolate mofetil, cyclosporine A (CsA), tacrolimus, adalimumab and sarilumab were effective in NINA uveitis. Rituximab combined with MTX was effective in PU. Interferon-β was superior to MTX, albeit with more adverse events in IU with ME. CsA was similar to cyclophosphamide (Cyc) in Behçet uveitis. Tacrolimus was safer and similar to CsA. Cyc was effective in serpiginoid choroiditis, but when combined with azathioprine in PU, but did not improve VA. Secukinumab did not prevent NINA uveitis recurrences, although intravenously it showed a higher response rate than when used subcutaneously. Daclizumab did not show any benefits in Behçet NINA uveitis.

CONCLUSION

Several IMDs and their combinations can be useful in treating NINA uveitis. The available studies were heterogeneous regarding patient characteristics and outcomes.

The effects of intravitreal adalimumab injection on pseudophakic macular edema

Objective

Pseudophakic macular edema is a frequent complication following cataract surgery. Inflammation is a major etiologic factor in the development of pseudophakic cystoid macular edema. Tumor necrosis factor-alpha has an important role in ocular inflammation. Adalimumab (Humira) is an inhibitor of tumor necrosis factor-alpha that has been approved in the United States. An open-label, uncontrolled, prospective, interventional study of five consecutive patients (5 eyes) with cystoid macular edema who were treated with off-label intravitreal adalimumab at Khalili Hospital was conducted. Slit-lamp examination and optical coherence tomography were done for all patients.

Results

No statistically significant difference was detected between best corrected visual acuity and central macular thickness before and after injection in pseudophakic macular edema. One patient developed uveitis approximately 2 weeks after injection. Based on the results, adalimumab does not appear to be an effective treatment for pseudophakic macular edema, and it may cause uveitis. Caution should be exercised when using this drug.

Trial registration Iranian Registry of Clinical Trials IRCT2016100430130N1, 2016.12.03, Retrospectively registered

Claudin-5 Redistribution Induced by Inflammation Leads to Anti-VEGF-Resistant Diabetic Macular Edema

Approximately 40% of patients with diabetic macular edema (DME) are resistant to anti-vascular endothelial growth factor (VEGF) therapy (rDME). Here, we demonstrate that significant correlations between inflammatory cytokines and VEGF, as observed in naive DME, are lost in patients with rDME. VEGF overexpression in the mouse retina caused delayed inflammatory cytokine upregulation, monocyte/macrophage infiltration (CD11b⁺ Ly6C⁺ CCR2⁺ cells), macrophage/microglia activation (CD11b⁺ CD80⁺ cells), and blood-retinal barrier disruption due to claudin-5 redistribution, which did not recover with VEGF blockade alone. Phosphorylated protein analysis of VEGF-overexpressed retinas revealed rho-associated coiled-coil-containing protein kinase (ROCK) activation. Administration of ripasudil, a selective ROCK inhibitor, attenuated retinal inflammation and claudin-5 redistribution. Ripasudil also contributed to the stability of claudin-5 expression by both transcriptional enhancement and degradation suppression in inflammatory cytokine-stimulated endothelium. Notably, the anti-VEGF agent and the ROCK inhibitor were synergic in suppressing cytokine upregulation, monocyte/macrophage infiltration, macrophage/microglia activation, and claudin-5 redistribution. Furthermore, in vitro analysis confirmed that claudin-5 redistribution depends on ROCK2 but not on ROCK1. This synergistic effect was also confirmed in human rDME cases. Our results suggest that ROCK-mediated claudin-5 redistribution by inflammation is a key mechanism in the anti-VEGF resistance of DME.

The Evolving Treatment of Diabetic Retinopathy

Purpose

To review the current therapeutic options for the management of diabetic retinopathy (DR) and diabetic macular edema (DME) and examine the evidence for integration of laser and pharmacotherapy.

Methods

A review of the PubMed database was performed using the search terms diabetic retinopathy, diabetic macular edema, neovascularization, laser photocoagulation, intravitreal injection, vascular endothelial growth factor (VEGF), vitrectomy, pars plana vitreous surgery, antiangiogenic therapy. With additional cross-referencing, this yielded 835 publications of which 301 were selected based on content and relevance.

Results

Many recent studies have evaluated the pharmacological, laser and surgical therapeutic strategies for the treatment and prevention of DR and DME. Several newer diagnostic systems such as optical coherence tomography (OCT), microperimetry, and multifocal electroretinography (mfERG) are also assisting in further refinements in the staging and classification of DR and DME. Pharmacological therapies for both DR and DME include both systemic and ocular agents. Systemic agents that promote intensive glycemic control, control of dyslipidemia and antagonists of the renin-angiotensin system demonstrate beneficial effects for both DR and DME. Ocular therapies include anti-VEGF agents, corticosteroids and nonsteroidal anti-inflammatory drugs. Laser therapy, both as panretinal and focal or grid applications continue to be employed in management of DR and DME. Refinements in laser devices have yielded more tissue-sparing (subthreshold) modes in which many of the benefits of conventional continuous wave (CW) lasers can be obtained without the adverse side effects. Recent attempts to lessen the burden of anti-VEGF injections by integrating laser therapy have met with mixed results. Increasingly, vitreoretinal surgical techniques are employed for less advanced stages of DR and DME. The development and use of smaller gauge instrumentation and advanced anesthesia agents have been associated with a trend toward earlier surgical intervention for diabetic retinopathy. Several novel drug delivery strategies are currently being examined with the goal of decreasing the therapeutic burden of monthly intravitreal injections. These fall into one of the five categories: non-biodegradable polymeric drug delivery systems, biodegradable polymeric drug delivery systems, nanoparticle-based drug delivery systems, ocular injection devices and with sustained release refillable devices. At present, there remains no one single strategy for the management of the particular stages of DR and DME as there are many options that have not been rigorously tested through large, randomized, controlled clinical trials.

Conclusion

Pharmacotherapy, both ocular and systemic, will be the primary mode of intervention in the management of DR and DME in many cases when cost and treatment burden are less constrained. Conventional laser therapy has become a secondary intervention in these instances, but remains a first-line option when cost and treatment burden are more constrained. Results with subthreshold laser appear promising but will require more rigorous study to establish its role as adjunctive therapy. Evidence to support an optimal integration of the various treatment options is lacking. Central to the widespread adoption of any therapeutic regimen for DR and DME is substantiation of safety, efficacy, and cost-effectiveness by a body of sound clinical trials.

The effect of infliximab and octreotide on cytokine levels experimental proliferative vitreoretinopathy

Purpose: To investigate the efficiency of intravitreal octreotide, which has previously been shown to have benefits in the treatment of proliferative vitreoretinopathy (PVR), and intravitreal infliximab as a novel option in an experimental dispase-induced PVR model.Methods: A total of 28 pigmented guinea pigs were divided into four groups, and each group consisted of seven subjects. Group 1 (control) was treated with a 0.2 mL saline solution intravitreally from 1.5 mm behind the limbus. Group 2 (sham) was treated with 0.07 IU/0.1 mL dispase 0.1 mL saline solution using the same method. Group 3(infliximab) received 0.07 IU/0.1 mL dispase and 1 mg/0.1 mL infliximab, and group 4(octreotide) was treated with 0.07 IU/0.1 mL dispase and 1 mg/0.1 mL octreotide. An intravitreal injection of infliximab and octreotide was administered to groups 3 and 4 two times during the experiment. The subjects were held for a 10-week period to await for the formation of PVR. At the end of ten weeks, the eyes were enucleated, and tumour necrosis factor-alpha (TNF-α), interleukin 1(IL-1), interleukin 6 (IL-6), transforming growth factor (TGF-β), and platelet-derived growth factor (PDGF) and levels in homogenised retina tissue were measured using the enzyme linked-immuno-sorbent assay (ELISA) method.Results: Retinal TNF-α, IL-1, IL-6, and PDGF levels had significantly decreased in treatment groups compared to the sham group (p < 0.05). The decrease in the level of TGF-β was not statistically significant between the treatment and the sham groups (p > 0.05).Conclusions: Intravitreal infliximab can inhibit the development of PVR and reduce levels of cytokine, which plays an essential role in the pathogenesis of PVR. The results of our study suggest that it may be possible to identify the ideal adjuvant pharmacological drugs that are effective in preventing PVR.

Insights into the pathogenesis of cystoid macular edema: leukostasis and related cytokines

Cystoid macular edema (CME) is the abnormal collection of intraretinal fluid in the macular region, especially in the inner nuclear and outer plexiform layers. CME leads to severe visual impairment in patients with various retinal diseases, such as diabetic retinopathy, retinal vascular occlusion, choroidal neovascularization, and uveitis. Although various retinal conditions lead to CME, a shared pathogenesis of CME is involved in these diseases. Accordingly, the pathogenesis of CME based on vasogenic mechanisms is first discussed in this review, including vascular hyperpermeability, leukostasis, and inflammation. We then describe cytotoxic mechanisms based on retinal Müller cell dysfunction. This comprehensive review will provide an understanding of the pathogenesis of CME for potential therapeutic strategies.

The efficacy of systemic and intravitreal infliximab treatments in an endotoxin-induced uveitis model

Purpose: To compare the efficacy of systemic and intravitreal infliximab treatments in an experimental endotoxin-induced uveitis (EIU) model. Methods: Twenty-eight white New Zealand rabbits were equally divided into 4 groups. Group 1 received an intravitreal injection of 0.1 cc saline, group 2 received an intravitreal injection of 2 µg/0.1 cc lipopolysaccharide (LPS), group 3 received an intravitreal injection of 2 µg/0.1 cc LPS and 2 mg/0.1 cc infliximab, and group 4 received intravitreal injection of 2 µg/0.1 cc LPS and intravenous injection of 5 mg/kg infliximab. Clinical, biochemical (aqueous and vitreous humour protein levels and TNF-α concentrations), and histopathological evaluations were performed. Results: The clinical examination score was lower in group 4 than in group 2 (p = 0.006); but there was no significant difference between groups 2 and 3 (Bonferroni correction, p = 0.016). No statistically significant difference was found among groups 2, 3, and 4 for aqueous humour protein levels (p > 0.05). Significantly higher aqueous humour concentrations of TNF-α was measured in group 3 comparing to both group 1 and 4 (p = 0.003 and p = 0.002, respectively). No significant difference was found in vitreous protein levels or TNF-α concentrations among all study groups (Bonferroni correction, p = 0.026 and p = 0.101, respectively). Histopathological evaluation of the uveal tissue and anterior chamber reaction revealed the highest inflammation in group 3 (p < 0.001). In group 4, histopathological evaluation of uveal tissue was lower than in groups 2 and 3 (p < 0.001 and p = 0.001, respectively); whereas there was no difference in anterior chamber inflammation between groups 2 and 4 (p = 1.00). Conclusion: Intravitreal 2 mg/0.1 cc infliximab injection exacerbated inflammation in an EIU model; whereas systemic infliximab treatment at a dose of 5 mg/kg suppressed inflammation effectively and rapidly.

Ocular complications of tumour necrosis factor alpha inhibitors

Tumour necrosis factor alpha inhibitors are a relatively recent development and are becoming increasingly common in the management of many chronic inflammatory conditions such as rheumatoid arthritis, inflammatory bowel disease, ankylosing spondylitis and juvenile idiopathic arthritis. However, their ocular side effect profile is incomplete and poorly recognised, with mostly anecdotal cases reported in the literature. In this report we review the literature regarding ocular side effects associated with tumour necrosis factor alpha blockade.

Neuroinflammation in Retinitis Pigmentosa, Diabetic Retinopathy, and Age-Related Macular Degeneration: A Minireview

The eye is an immuno-privileged organ. However, certain diseases such as uveitis are intrinsically linked to inflammation. In several retinal degenerative diseases, there is a unique damage at the onset of the disease, but evidence suggests that chronic and low-grade inflammatory processes play an important role in their progression. Studies have identified similar signaling pathways and changes in resident immune cells within the retina among these diseases. Herein, we will discuss some of these studies and propose how understanding this inflammatory response could aid in the development of therapies.

Diabetic Retinopathy-An Underdiagnosed and Undertreated Inflammatory, Neuro-Vascular Complication of Diabetes

Diabetes mellitus is a world-wide epidemic and diabetic retinopathy, a devastating, vision-threatening condition, is one of the most common diabetes-specific complications. Diabetic retinopathy is now recognized to be an inflammatory, neuro-vascular complication with neuronal injury/dysfunction preceding clinical microvascular damage. Importantly, the same pathophysiologic mechanisms that damage the pancreatic β-cell (e.g., inflammation, epigenetic changes, insulin resistance, fuel excess, and abnormal metabolic environment), also lead to cell and tissue damage causing organ dysfunction, elevating the risk of all complications, including diabetic retinopathy. Viewing diabetic retinopathy within the context whereby diabetes and all its complications arise from common pathophysiologic factors allows for the consideration of a wider array of potential ocular as well as systemic treatments for this common and devastating complication. Moreover, it also raises the importance of the need for methods that will provide more timely detection and prediction of the course in order to address early damage to the neurovascular unit prior to the clinical observation of microangiopathy. Currently, treatment success is limited as it is often initiated far too late and after significant neurodegeneration has occurred. This forward-thinking approach of earlier detection and treatment with a wider array of possible therapies broadens the physician's armamentarium and increases the opportunity for prevention and early treatment of diabetic retinopathy with preservation of good vision, as well the prevention of similar destructive processes occurring among other organs.

Tofacitinib for refractory uveitis and scleritis

Purpose

To report the successful use of tofacitinib in the treatment of refractory uveitis and scleritis.

Observations

Two patients, one with scleritis and another with anterior and intermediate uveitis, presented with refractory disease after failure of multiple steroid-sparing therapies. Treatment with tofacitinib led to durable resolution of uveitis and scleritis.

Conclusions and importance

Tofacitinib is a potential novel treatment option for refractory, noninfectious inflammatory eye disease.

The Management of Acute Anterior Uveitis Complicating Spondyloarthritis: Present and Future

Spondyloarthropathies (SpA) encompass a group of chronic inflammatory diseases sharing common genetic and clinical features, including the association with HLA-B27 antigen, the involvement of both the axial and the peripheral skeleton, the presence of dactylitis, enthesitis, and typical extra-articular manifestations such as psoriasis, inflammatory bowel disease, and acute anterior uveitis (AAU). The latter is commonly reported as a noninfectious acute inflammation of the anterior uveal tract and its adjacent structures. AAU may affect more than 20% of SpA patients representing the most common extra-articular manifestation of the disease. Considering the potential consequences of untreated AAU, early diagnosis and aggressive treatment are crucial to avoid complications of remittent or chronic eye inflammation, such as visual loss and blindness. The management of SpA has dramatically improved over the last decades due to the development of new treat-to-target strategies and to the introduction of biologic disease modifying antirheumatic drugs (bDMARDs), particularly tumor necrosis factor alpha inhibitors (TNFis), currently used for the treatment of nonresponder patients to conventional synthetic agents. Along with the improvement of musculoskeletal features of SpA, bDMARDs provided an additional effect also in the management of AAU in those patients who are failures to topical and systemic conventional therapies. Nowadays, five TNFis, one interleukin-17, and one interleukin 12/23 blocker are licensed for the treatment of SpA, with different proven efficacy in preventing and treating ocular involvement. The aim of this review is to summarize the current options and to analyze the future perspectives for the management of SpA-associated AAU.

Efficacy and safety of intravitreal anti-tumour necrosis factor drugs in adults with non-infectious uveitis - a systematic review

Anti-tumour necrosis factor (TNF) drugs have been extensively used in non-infectious uveitis (NIU), when corticosteroids or conventional immunosuppressive drugs cannot adequately control inflammation or intolerable side-effects occur. However, systemic anti-TNF therapies are also associated with a myriad of side-effects. Therefore, intravitreal administration of anti-TNF biologics has been employed to minimize patient morbidity and systemic adverse effects, while maintaining therapeutic effectivity. We undertook a systematic review to determine evidence of efficacy and safety of intravitreal administration of anti-TNF drugs in adults with NIU. We conducted this systematic review according to the PRISMA guidelines. The protocol was registered with PROSPERO (CRD42016041946). We searched CENTRAL, MEDLINE and EMBASE, from inception to April 2017, as well as clinical trial registries and grey literature. The qualitative analysis included all studies of adult patients with a diagnosis of NIU and who received intravitreal anti-TNF drugs with a 4-week minimum follow-up. A total of 4840 references were considered for title and abstract screening. Seven full texts were screened, and five studies were considered for analysis. All studies were open-label, single-centre, prospective, non-randomized, interventional case series with a follow-up between 4 and 26 weeks, employing either adalimumab in two studies and infliximab in three. Three studies showed a treatment effect of anti-TNF intravitreal injections, while one study revealed short-term improvement and one study revealed no efficacy of anti-TNF intravitreal therapy. None of the studies reported ocular adverse effects but only two studies included electrophysiological assessment in the safety analysis and no study assessed systemic human anti-drug antibodies. The available evidence is not sufficiently robust to conclude about the clinical effectivity of intravitreal anti-TNF in NIU and so no recommendation can be made. In conclusion, intravitreal injection of anti-TNF antibodies remains a possible treatment option to be explored through robust clinical investigation.

Systemic factors related to soluble (pro)renin receptor in plasma of patients with proliferative diabetic retinopathy

(Pro)renin receptor [(P)RR], a new component of the tissue renin-angiotensin system (RAS), plays a crucial role in inflammation and angiogenesis in the eye, thus contributing to the development of proliferative diabetic retinopathy (PDR). In this study, we investigated systemic factors related to plasma levels of soluble form of (P)RR [s(P)RR] in patients with PDR. Twenty type II diabetic patients with PDR and 20 age-matched, non-diabetic patients with idiopathic macular diseases were enrolled, and plasma levels of various molecules were measured by enzyme-linked immunosorbent assays. Human retinal microvascular endothelial cells were stimulated with several diabetes-related conditions to evaluate changes in gene expression using real-time quantitative PCR. Of various systemic parameters examined, the PDR patients had significantly higher blood sugar and serum creatinine levels than non-diabetic controls. Protein levels of s(P)RR, prorenin, tumor necrosis factor (TNF)-α, complement factor D (CFD), and leucine-rich α-2-glycoprotein 1 (LRG1) significantly increased in the plasma of PDR subjects as compared to non-diabetes, with positive correlations detected between s(P)RR and these inflammatory molecules but not prorenin. Estimated glomerular filtration rate and serum creatinine were also correlated with plasma s(P)RR, but not prorenin, levels. Among the inflammatory molecules correlated with s(P)RR in the plasma, TNF-α, but not CFD or LRG1, application to retinal endothelial cells upregulated the mRNA expression of (P)RR but not prorenin, while stimulation with high glucose enhanced both (P)RR and prorenin expression. These findings suggested close relationships between plasma s(P)RR and diabetes-induced factors including chronic inflammation, renal dysfunction, and hyperglycemia in patients with PDR.

Infliximab exerts a dose-dependent effect on retinal safety in the albino rabbit

PURPOSE

To assess the retinal toxicity of an intravitreal injection of infliximab, a monoclonal antibody to tumor necrosis factor α, in a rabbit model.

MATERIALS AND METHODS

Two groups of adult albino rabbits (n = 5) received intravitreal injections of infliximab (0.1 ml) in the study eye and balanced salt solution (BSS, 0.1 ml) in the control eye at baseline. Group 1 was administered with 1.5 mg/0.1 ml, and group 2 was injected with 7.5 mg/0.1 ml of infliximab solution. Electroretinography (ERG) was performed at baseline and at 1, 7, 30, and 45 days after the injection. Visual evoked potentials (VEPs) were recorded at 7 and 45 days after the injection. After the last electrophysiological assessment, the rabbits were euthanized and retinal histopathology and immunhistochemistry for glial fibrillary acidic protein (GFAP) were performed.

RESULTS

ERG responses demonstrated no significant deficit in retinal function in eyes injected with infliximab. Mean dark-adapted a-wave and b-wave maximal amplitude and semi-saturation constant values at baseline and throughout the 45 days of follow-up after the injection indicated no remarkable difference in outer retinal function between the control and experimental eyes. VEP responses were similar at each time point (7 and 45 days). No difference was seen in retinal histopathology and immunocytochemistry sections in eyes receiving the 1.5 mg/0.1 ml dose compared to the control eyes. However, increased GFAP labeling in retinal Müller cells was detected in rabbit eyes treated with the 7.5 mg/0.1 ml dose.

CONCLUSIONS

Intravitreal injection of 1.5 mg/0.1 ml infliximab dose has no toxic effect on the integrity (functional or structural) of the retina in rabbits. A higher dose of 7.5 mg/0.1 ml may be slightly toxic as suggested by positive Müller cell GFAP expression. Additional studies of retinal toxicity at higher doses and after multiple injections are needed to establish the retinal safety of intravitreal infliximab therapy in humans.

INTRAVITREAL INFLIXIMAB IN REFRACTORY UVEITIS IN BEHCET'S DISEASE: A Safety and Efficacy Clinical Study

PURPOSE

To assess the safety and efficacy of intravitreal infliximab (1 mg/0.05 mL) in patients with refractory posterior uveitis in Behcet's disease.

METHODS

Twenty patients were included in this study. Best corrected visual acuity (BCVA), vitreous haze (graded 0-4), vasculitis, retinitis, and papillopathy (presence or absence) were assessed at baseline, Day 1 and Week 2, 4, 6, 8, 12, and 18. Optical coherence tomography (OCT) central foveal thickness, fluorescein angiography, and flash electroretinogram were done at baseline and 4, 12, and 18 weeks.

RESULTS

Mean baseline logMAR BCVA was 0.94 (20/160), had improved significantly by Week 2 to 0.6 (20/80) (P < 0.0001), and reached 0.36 (20/40) by Weeks 18 with three injections (P < 0.0001). Mean central foveal thickness OCT decreased significantly from baseline 361 μm to 180 μm at the end of follow-up (P < 0.0001). Profound decrease in mean vitreous haze gradings from two to 0.2 by the end follow-up (P < 0.05). There was a significant reduction in the number of patients with vasculitis (15 at baseline to 1 weeks at 18 weeks), retinitis (nine at baseline to none at 4 weeks), and papillitis (two at baseline to none at 4 weeks) (P < 0.05). No significant electrophysiological changes or ocular adverse inflammatory reactions were observed during the study period.

CONCLUSION

Intravitreal infliximab appeared to be safe and effective in treating uveitis in Behcet's disease and should be considered as an alternative to systemic therapies.

Sustained Subconjunctival Delivery of Infliximab Protects the Cornea and Retina Following Alkali Burn to the Eye

Purpose

Tumor necrosis factor (TNF)-α is upregulated in eyes following corneal alkali injury and contributes to corneal and also retinal damage. Prompt TNF-α inhibition by systemic infliximab ameliorates retinal damage and improves corneal wound healing. However, systemic administration of TNF-α inhibitors carries risk of significant complications, whereas topical eye-drop delivery is hindered by poor ocular bioavailability and the need for patient adherence. This study investigates the efficacy of subconjunctival delivery of TNF-α antibodies using a polymer-based drug delivery system (DDS).

Methods

The drug delivery system was prepared using porous polydimethylsiloxane/polyvinyl alcohol composite fabrication and loaded with 85 μg of infliximab. Six Dutch-belted pigmented rabbits received ocular alkali burn with NaOH. Immediately after the burn, subconjunctival implantation of anti-TNF-α DDS was performed in three rabbits while another three received sham DDS (without antibody). Rabbits were followed with photography for 3 months.

Results

After 3 months, the device was found to be well tolerated by the host and the eyes exhibited less corneal damage as compared to eyes implanted with a sham DDS without drug. The low dose treatment suppressed CD45 and TNF-α expression in the burned cornea and inhibited retinal ganglion cell apoptosis and optic nerve degeneration, as compared to the sham DDS treated eyes. Immunolocalization revealed drug penetration in the conjunctiva, cornea, iris, and choroid, with residual infliximab in the DDS 3 months after implantation.

Conclusions

This reduced-risk biologic DDS improves corneal wound healing and provides retinal neuroprotection, and may be applicable not only to alkali burns but also to other inflammatory surgical procedures such as penetrating keratoplasty and keratoprosthesis implantation.

Proangiogenic characteristics of activated macrophages from patients with age-related macular degeneration

Macrophages were previously implicated in the pathogenesis of neovascular age-related macular degeneration (nvAMD). It is unclear if a specific macrophage phenotype is associated with nvAMD, and if macrophages from nvAMD patients are more pathogenic as compared with controls. To address these issues, we evaluated macrophages derived from peripheral blood monocytes of nvAMD patients and age-matched controls. Macrophages were assessed in terms of their expression profile and of their angiogenic potential in the choroid sprouting assay and the rat model of laser-induced choroidal neovascularization. Results showed a proangiogenic and inflammatory gene and protein expression profiles in classic (M[IFNγ and LPS]) and alternative (M[IL-4 and IL-13]) polarized macrophages. Furthermore, activated macrophages, particularly of the M(IFNγ and LPS) phenotype from nvAMD patients, were proangiogenic ex vivo and in vivo. These findings implicate activated human macrophages, particularly M(IFNγ and LPS) macrophages from nvAMD patients, in nvAMD. Further research is required to determine whether activated macrophages can serve as therapeutic targets in nvAMD.

Basigin can be a therapeutic target to restore the retinal vascular barrier function in the mouse model of diabetic retinopathy

Despite the advance in medical technology, diabetic retinopathy (DR) is still an intractable disease which leads to the damage of retinal cells and finally the visual loss. Impairment of retinal vascular barrier triggered by an admixture of multiple inflammatory cytokines is a core of pathophysiology of DR. Therefore, the molecules involved commonly in multiple cytokines-induced impairment of vascular barrier would be the targets of curative treatment of DR. Here, we demonstrate that basigin, a transmembrane molecule expressed in neural barrier-forming endothelial cells, is the molecule essential for vascular barrier impairment which is shared by various triggers including VEGF, TNFα and IL-1β. In vitro data with neural microvascular endothelial cells indicated that stimulation with cytokines decreases the levels of claudin-5 in cell membranes and consequently impairs the barrier function in a manner dependent on the interaction of claudin-5 with basigin and caveolin-1. In addition, the increased vascular permeability in retinas of streptozotocin-induced diabetic mice was shown to be clearly normalized by intravitreous injection of siRNAs specific for basigin. This study has highlighted basigin as a common essential molecule for various stimuli-induced impairment of retinal vascular barrier, which can be a target for strategies to establish a curative treatment of DR.

An anti-TNF-α antibody mimetic to treat ocular inflammation

Infliximab is an antibody that neutralizes TNF-α and is used principally by systemic administration to treat many inflammatory disorders. We prepared the antibody mimetic Fab-PEG-Fab (FpF_infliximab) for direct intravitreal injection to assess whether such formulations have biological activity and potential utility for ocular use. FpF_infliximab was designed to address side effects caused by antibody degradation and the presence of the Fc region. Surface plasmon resonance analysis indicated that infliximab and FpF_infliximab maintained binding affinity for both human and murine recombinant TNF-α. No Fc mediated RPE cellular uptake was observed for FpF_infliximab. Both Infliximab and FpF_infliximab suppressed ocular inflammation by reducing the number of CD45+ infiltrate cells in the EAU mice after a single intravitreal injection at the onset of peak disease. These results offer an opportunity to develop and formulate for ocular use, FpF molecules designed for single and potentially multiple targets using bi-specific FpFs.

Moving Past Anti-VEGF: Novel Therapies for Treating Diabetic Retinopathy

Diabetic retinopathy is the leading cause of blindness in working age adults, and is projected to be a significant future health concern due to the rising incidence of diabetes. The recent advent of anti-vascular endothelial growth factor (VEGF) antibodies has revolutionized the treatment of diabetic retinopathy but a significant subset of patients fail to respond to treatment. Accumulating evidence indicates that inflammatory cytokines and chemokines other than VEGF may contribute to the disease process. The current review examines the presence of non-VEGF cytokines in the eyes of patients with diabetic retinopathy and highlights mechanistic pathways in relevant animal models. Finally, novel drug targets including components of the kinin-kallikrein system and emerging treatments such as anti-HPTP (human protein tyrosine phosphatase) β antibodies are discussed. Recognition of non-VEGF contributions to disease pathogenesis may lead to novel therapeutics to enhance existing treatments for patients who do not respond to anti-VEGF therapies.

Blockade of Tumor Necrosis Factor-Alpha: A Role for Adalimumab in Neovascular Age-Related Macular Degeneration Refractory to Anti-Angiogenesis Therapy?

AIMS

To report a case of wet age-related macular degeneration (wet-AMD) refractory to intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy in a patient who showed visual and anatomical improvement and stabilization after starting a subcutaneous treatment course with adalimumab, an anti-tumor necrosis factor-alpha (TNF-α) drug, for concomitant Crohn's disease.

METHODS

Observational case report of a female patient. Ophthalmological evaluation was performed by slit lamp and ophthalmoscopy (posterior pole and anterior segment). Best-corrected visual acuity (BCVA) was determined, and imaging was performed by fluorescein angiography, indocyanine green angiography, and optical coherence tomography (OCT). Intravitreal therapies used and treatment with anti-TNF-α were recorded.

RESULTS

A 64-year-old woman with wet-AMD was treated with fourteen intravitreal injections of ranibizumab (0.5 mg) for a period of 40 months with intervals of 1-6 months. She initially showed a good visual and anatomical response to periodic anti-VEGF treatment but during check visits, anatomical and functional responses deteriorated. At the 40-month follow-up, the patient had developed Crohn's disease, and her rheumatologist started treatment with adalimumab (40 mg subcutaneously every 2 weeks). During the 25 months of treatment with adalimumab, the patient did not require any additional intravitreal anti-VEGF treatments because her BCVA, clinical, and OCT findings improved and remained stable.

CONCLUSIONS

We described a case of a patient with wet-AMD refractory to anti-VEGF therapy, which clinically benefited from subcutaneous adalimumab therapy. Treatment with subcutaneous anti-TNF-α in combination with anti-VEGF therapy avoids the high cost and risks related to multiple intravitreal anti-VEGF injections with good functional and anatomic outcomes.

Intravitreal drug administration for treatment of noninfectious uveitis

Intravitreal treatment became popular with the discovery of the blood ocular barriers, which significantly limit drug penetration in systemic or topical administration. As the mainstay of treatment in noninfectious uveitis (NOIU) is still corticosteroids, triamcinolone acetonide (TA) was the first intravitreally used agent in this subset of patients. Although it was very effective in controlling inflammation and improving the inflammation related complications, TA was found to have a high rate of intraocular complications and a relatively short half-life necessitating frequent reinjections. Other systemically used therapeutic options such as methotrexate and anti-tumor necrosis factor-α agents were also tried intravitreally. Additionally anti-vascular endothelial growth factor agents that are widely used intravitreally in the management of diabetic retinopathy and age related macular degeneration have become an option to control the uveitis related complications like macular edema, retinal and choroidal neovascularizations. Advances in biotechnology led to the slow release biodegradable implant era. These implants have a longer duration of action, which may help in decreasing the number of reinjections. Today two forms of implants have been approved for use in NOIU, Retisert (0.59 mg flucinolone acetonide, surgical intervention) and Ozurdex (0.7 mg dexamethasone, office based intervention). Studies dealing with newer agents (cyclosporine, LFG31, sirolimus) in the management of chronic NOIU are on the way. The search for ideal effective, safe and biocompatible intravitreal agents in the management of NOIU has not ended yet.

The effect of disease-modifying antirheumatic drugs on retinal function in the electrophysiological ex vivo model of the isolated perfused vertebrate retina

BACKGROUND

Disease-modifying antirheumatic drugs (DMARDs) have been suggested in the treatment of inflammatory ophthalmological diseases. The aim of the present study was to investigate the effects of these DMARDs on bovine retinal function.

METHODS

Bovine retina preparations were perfused with a standard solution. After recording stable electroretinograms the nutrient solution was substituted by a DMARD medium with varying concentrations of different drugs (etanercept and infliximab) for 30 min. Afterwards b-wave recovery was observed.

RESULTS

Significant decreases in the b-wave amplitude (p < 0.05) were found for etanercept 0.5 mg/ml (p = 0.0022). Infliximab 2 mg/ml (p = 0.1276) did not result in any statistically significant b-wave reduction.

CONCLUSION

The presented data suggest that infliximab might have the better safety profile than etanercept.

Intravitreal Adalimumab in Active Noninfectious Uveitis: A Pilot Study

PURPOSE

To evaluate the short-term efficacy of intravitreal adalimumab (IVA) for the treatment of eyes with active noninfectious uveitis.

METHODS

Consecutive eyes with active noninfectious uveitis were injected with IVA at 0, 2, then every 4 weeks for total of 26 weeks.

RESULTS

Six out of 7 patients (12 of 13 eyes) completed 26 weeks of treatment. One patient (1 eye) failed treatment. Seven out of 12 eyes had improvement of ≥2 ETDRS lines. Three out of three eyes had resolution of anterior chamber cells. And 9 of 10 eyes with vitreous haze had zero haze at 26 weeks. Five out of 8 eyes with macular edema had complete resolution. Median fluorescein angiography score improved from 14 to 4 on last follow-up.

CONCLUSIONS

IVA was effective in controlling the inflammation, decreasing the macular edema, and improving the best corrected visual acuity in the majority of eyes in this series.

Spectral domain-optical coherence tomographic findings in patients with ankylosing spondylitis under anti-tumor necrosis factor-alpha therapy

OBJECTIVE

To evaluate the effect of tumor necrosis factor-alpha (TNF-α) blockade on the thickness of the peripapillary retinal nerve fiber layer (RNFL), the ganglion cell-inner plexiform layers (GCIPL), and the macula in ankylosing spondylitis (AS) patients under anti-TNF-α therapy.

MATERIALS AND METHODS

Twenty-one patients with AS received etanercept, or adalimumab, or infliximab for at least 6 months. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) levels, and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores were measured before and 6 months after the beginning of the treatment. Peripapillary RNFL, four regional fields (superior, inferior, nasal, and temporal), GCIPL, and macular thicknesses of the patients were analyzed by optical coherence tomography before the treatment, at 3 months and 6 months after the beginning of the treatment.

RESULTS

The mean BASDAI, ESR, and CRP values were 5.2 ± 1.5, 31.6 ± 21.7, and 15.7 ± 13.9, respectively, at the beginning of the treatment and 2.3 ± 1.7, 21.3 ± 15.1, and 10.1 ± 10.3, respectively, 6 months after the beginning of treatment. There were significant differences among the mean BASDAI, ESR, and CRP values at the beginning of treatment and 6 months later (p < 0.001, p = 0.007, and p = 0.009, respectively). There were no significant differences among peripapillary RNFL (p = 0.24), four regional fields (p = 0.98, p = 0.23, p = 0.09, p = 0.47), GCIPL (p = 0.25), or macular (p = 0.33) thicknesses of the patients during anti-TNF-α treatment. In addition, the mean intraocular pressure levels throughout the follow-up did not show significant variation on repeated-measures ANOVA (p = 0.77).

CONCLUSIONS

TNF-α blockade does not seem to influence RNFL, GCIPL, or macular thickness of patients with AS in the short term.

Update on intravitreal anti-tumor necrosis factor alpha therapies for ocular disorders

Tumor necrosis factor alpha (TNF-?) is an important pro-inflammatory cytokine associated with a variety of ocular diseases. The currently available TNF-? inhibitors are etanercept, infliximab, adalimumab, golimumab, and certolizumab. Experimental and clinical studies on the intravitreal use of these agents have been reported with etanercept, infliximab, and adalimumab: etanercept has shown limited efficacy in scarce reports; infliximab has been associated with local safety concerns but appears to benefit certain cases; adalimumab has shown no efficacy in cases of age-related macular degeneration (AMD) or diabetic macular edema (DME), but the combination with bevacizumab may be effective in refractory cases of macular diseases. Further preclinical and clinical studies are warranted in order to be able to obtain a more robust conclusion on the use of intravitreal TNF-? inhibitors.

TNF inhibition for ophthalmic indications: current status and outlook

BACKGROUND

Tumor necrosis factors (TNF) are a group of cytokines that play a role in systemic inflammation, stimulating the acute phase reaction. They are involved in systemic rheumatologic conditions such as rheumatoid arthritis and juvenile idiopathic arthritis, as well as ocular inflammatory conditions in the uveitis spectrum. Several drugs were developed to inhibit the action of TNF, thereby reducing inflammation. The three most commonly used TNF inhibitors in the US are etanercept, infliximab, and adalimumab. Newer drugs include certolizumab and golimumab. In this review, we discuss the differences in the mechanism of action, route of administration, indication, and efficacy of TNF inhibitors used in the treatment of ocular inflammation.

METHODS

A review of the literature in the PubMed, MEDLINE, and Cochrane databases was conducted to identify clinical trials, comparative studies, case series, and case reports describing the use of tumor necrosis factor inhibitors in uveitis therapy. The search was limited to primary reports published in English with human subjects from 1990 to the present, yielding 5,238 manuscripts. In addition, referenced articles from the initial searches were hand searched to identify additional relevant reports. After title and abstract selection, duplicate elimination, and manual search, 69 papers were selected for analysis. Exclusion criteria included review articles and case reports on the efficacy of etanercept, infliximab, and adalimumab. Manuscripts with fewer than 20 study subjects were excluded if other larger studies existed on the use of the same drug for a particular indication. Studies with <6 months of patient follow-up were also excluded, except in the case where no other data were available. Articles meeting these criteria were then reviewed by the three authors for inclusion in this review.

RESULTS

Tumor necrosis factor inhibitors have been shown to decrease inflammation associated with a number of rheumatologic conditions. Three of the five commercially available TNF inhibitors-etanercept, infliximab, and adalimumab-have been studied for their efficacy in treatment of ocular inflammation. Etanercept appears to be inadequate in controlling ocular inflammation and is not recommended for the treatment of uveitis. Infliximab and adalimumab, however, have shown encouraging results in multiple trials. Serious potential side effects such as infection, including reactivation of latent tuberculosis, malignancy, and demyelinating disease, may limit the use of TNF inhibitors in uveitis. Proper screening of patients prior to initiating these therapies may decrease these risks.

DISCUSSION

Early success with infliximab and adalimumab has paved the way for new TNF inhibitors and other corticosteroid-sparing drugs to emerge in the treatment of ocular inflammation. Future studies are on the horizon to determine the long-term safety and efficacy of newer TNF inhibitors such as certolizumab and golimumab.

Homocysteine is linked to macular edema in type 2 diabetes

AIM

To explore the relationship between plasma total homocysteine concentration and diabetic macular edema in patients with type 2 diabetes.

METHODS

Patients with type 2 diabetes (n = 176) were enrolled in a cross-sectional hospital-based study. Diabetic macular edema status was documented by fundus photographs. Plasma total homocysteine concentration was measured using fluorescence polarization immunoassay. Normal control plasma homocysteine was established in 115 healthy subjects. Risk factors for diabetic macular edema were obtained from fasting blood samples and interviewer questionnaire.

RESULTS

Diabetic patients had increased plasma homocysteine compared with normal control. Plasma homocysteine levels were higher in subjects with diabetic macular edema than without ((11.4 ± 2.7) versus (8.5 ± 1.9) (μmol/l), p = 0.000). The association of homocysteine with diabetic macular edema was independent of major risk factors for diabetic macular edema (duration of diabetes, HbA1c, lipid) and determinants of higher homocysteine concentration (age, gender, serum folate and vitamin B12, renal status, and biguanide use) (OR: 1.63 (1.02-2.14), p = 0.018). Furthermore, per increase of 5.0 μmol/l plasma homocysteine was related to macular edema, after controlling for per unit increase of other factors (OR: 1.64 (1.04-2.16), p = 0.019).

CONCLUSIONS

Plasma total homocysteine concentration is independently associated with the occurrence of macular edema in type 2 diabetes. Future prospective studies are warranted to clarify the relationship.