Evaluation of potential retinal toxicity of adalimumab (Humira)

The prophylactic value of TNF-α inhibitors against retinal cell apoptosis and optic nerve axon loss after corneal surgery or trauma

BACKGROUND AND PURPOSE

Late secondary glaucoma is an often-severe complication after acute events like anterior segment surgery, trauma and infection. TNF-α is a major mediator that is rapidly upregulated, diffusing also to the retina and causes apoptosis of the ganglion cells and degeneration of their optic nerve axons (mediating steps to glaucomatous damage). Anti-TNF-α antibodies are in animals very effective in protecting the retinal cells and the optic nerve-and might therefore be useful prophylactically against secondary glaucoma in future such patients. Here we evaluate (1) toxicity and (2) efficacy of two TNF-α inhibitors (adalimumab and infliximab), in rabbits by subconjunctival administration.

METHODS

For drug toxicity, animals with normal, unburned corneas were injected with adalimumab (0.4, 4, or 40 mg), or infliximab (1, 10, or 100 mg). For drug efficacy, other animals were subjected to alkali burn before such injection, or steroids (for control). The rabbits were evaluated clinically with slit lamp and photography, electroretinography, optical coherence tomography, and intraocular pressure manometry. A sub-set of eyes were stained ex vivo after 3 days for retinal cell apoptosis (TUNEL). In other experiments the optic nerves were evaluated by paraphenylenediamine staining after 50 or 90 days. Loss of retinal cells and optic nerve degeneration were quantified.

RESULTS

Subconjunctival administration of 0.4 mg or 4.0 mg adalimumab were well tolerated, whereas 40.0 mg was toxic to the retina. 1, 10, or 100 mg infliximab were also well tolerated. Analysis of the optic nerve axons after 50 days confirmed the safety of 4.0 mg adalimumab and of 100 mg infliximab. For efficacy, 4.0 mg adalimumab subconjunctivally in 0.08 mL provided practically full protection against retinal cell apoptosis 3 days following alkali burn, and infliximab 100 mg only slightly less. At 90 days following burn injury, control optic nerves showed about 50% axon loss as compared to 8% in the adalimumab treatment group.

CONCLUSIONS

Subconjunctival injection of 4.0 mg adalimumab in rabbits shows no eye toxicity and provides excellent neuroprotection, both short (3 days) and long-term (90 days). Our total. accumulated data from several of our studies, combined with the present paper, suggest that corneal injuries, including surgery, might benefit from routine administration of anti-TNF-α biologics to reduce inflammation and future secondary glaucoma.

Behçet's disease uveitis

Uveitis in Behçet's disease (BD) is frequent (40% of cases) and is a major cause of morbidity. The age of onset of uveitis is between 20 and 30 years. Ocular involvement includes anterior, posterior or panuveitis. It is non-granulomatous. Uveitis may be the first sign of the disease in 20% of cases or it may appear 2 or 3 years after the first symptoms. Panuveitis is the most common presentation and is more commonly found in men. Bilateralisation usually occurs on average 2 years after the first symptoms. The estimated risk of blindness at 5 years is 10-15%. BD uveitis has several ophthalmological features that distinguish it from other uveitis. The main goals in the management of patients are the rapid resolution of intraocular inflammation, prevention of recurrent attacks, achievement of complete remission, and preservation of vision. Biologic therapies have changed the management of intraocular inflammation. The aim of this review is to provide an update previous article by our team on pathogenesis, diagnostic approaches, identification of factors associated with relapse and the therapeutic strategy of BD uveitis.

Behçet's Disease Uveitis

Uveitis in Behçet's disease (BD) is frequent (40% of cases) and is a major cause of morbidity. The age of onset of uveitis is between 20 and 30 years. Ocular involvement includes anterior, posterior, or panuveitis. Uveitis may be the first sign of the disease in 20% of cases or it may appear 2 or 3 years after the first symptoms. Panuveitis is the most common presentation and is more commonly found in men. Bilateralization usually occurs on average 2 years after the first symptoms. The estimated risk of blindness at 5 years is 10-15%. BD uveitis has several ophthalmological features that distinguish it from other uveitis. The main goals in the management of patients are the rapid resolution of intraocular inflammation, the prevention of recurrent attacks, the achievement of complete remission, and the preservation of vision. Biologic therapies have changed the management of intraocular inflammation. The aim of this review is to provide an update to a previous article by our team on pathogenesis, diagnostic approaches, and the therapeutic strategy of BD uveitis.

Perspectives of Therapeutic Drug Monitoring of Biological Agents in Non-Infectious Uveitis Treatment: A Review

Biological drugs, especially those targeting anti-tumour necrosis factor α (TNFα) molecule, have revolutionized the treatment of patients with non-infectious uveitis (NIU), a sight-threatening condition characterized by ocular inflammation that can lead to severe vision threatening and blindness. Adalimumab (ADA) and infliximab (IFX), the most widely used anti-TNFα drugs, have led to greater clinical benefits, but a significant fraction of patients with NIU do not respond to these drugs. The therapeutic outcome is closely related to systemic drug levels, which are influenced by several factors such as immunogenicity, concomitant treatment with immunomodulators, and genetic factors. Therapeutic drug monitoring (TDM) of drug and anti-drug antibody (ADAbs) levels is emerging as a resource to optimise biologic therapy by personalising treatment to bring and maintain drug concentration within the therapeutic range, especially in those patients where a clinical response is less than expected. Furthermore, some studies have described different genetic polymorphisms that may act as predictors of response to treatment with anti-TNFα agents in immune-mediated diseases and could be useful in personalising biologic treatment selection. This review is a compilation of the published evidence in NIU and in other immune-mediated diseases that support the usefulness of TDM and pharmacogenetics as a tool to guide clinicians’ treatment decisions leading to better clinical outcomes. In addition, findings from preclinical and clinical studies, assessing the safety and efficacy of intravitreal administration of anti-TNFα agents in NIU are discussed.

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.

Identifying and Treating Ocular Manifestations in Psoriasis

Psoriasis is a chronic immune-mediated inflammatory skin condition that commonly presents with red, thickened, and scaling plaques. Given the prominent cutaneous manifestations of psoriasis, more subtle ophthalmic findings of the disease may initially go undetected, with the potential for significant ocular morbidity. Associated ocular disease can involve nearly any structure of the eye, with the eyelids most commonly being affected, resulting in relatively common signs and symptoms of ocular surface discomfort. The presence of intraocular inflammation (i.e., uveitis) or retinal involvement carry a heightened risk of vision loss, and are often more difficult to diagnose outside of the ophthalmology clinic. Early detection and treatment of ocular disease can limit morbidity and are critical to the management of these patients, which requires coordination of care between dermatologists and ophthalmologists. The objective of this article was to review the most common ocular conditions that affect psoriatic patients, when to consider referral to an ophthalmologist, and to summarize the adverse ocular effects of current psoriasis treatments.

Flavonoids as potential phytotherapeutics to combat cytokine storm in SARS-CoV-2

Emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, COVID-19, has become the global panic since December 2019, which urges the global healthcare professionals to identify novel therapeutics to counteract this pandemic. So far, there is no approved treatment available to control this public health issue; however, a few antiviral agents and repurposed drugs support the patients under medical supervision by compromising their adverse effects, especially in emergency conditions. Only a few vaccines have been approved to date. In this context, several plant natural products-based research studies are evidenced to play a crucial role in immunomodulation that can prevent the chances of infection as well as combat the cytokine release storm (CRS) generated during COVID-19 infection. In this present review, we have focused on flavonoids, especially epicatechin, epigallocatechin gallate, hesperidin, naringenin, quercetin, rutin, luteolin, baicalin, diosmin, ge nistein, biochanin A, and silymarin, which can counteract the virus-mediated elevated levels of inflammatory cytokines leading to multiple organ failure. In addition, a comprehensive discussion on available in silico, in vitro, and in vivo findings with critical analysis has also been evaluated, which might pave the way for further development of phytotherapeutics to identify the potential lead candidatetoward effective and safe management of the SARS-CoV-2 disease.

Old and New Challenges in Uveitis Associated with Behçet's Disease

Behçet’s disease (BD) is a systemic vasculitis disease of unknown origin occurring in young people, which can be venous, arterial or both, classically occlusive. Ocular involvement is particularly frequent and severe; vascular occlusion secondary to retinal vasculitis may lead to rapid and severe loss of vision. Biologics have transformed the management of intraocular inflammation. However, the diagnosis of BD is still a major challenge. In the absence of a reliable biological marker, diagnosis is based on clinical diagnostic criteria and may be delayed after the appearance of the onset sign. However, therapeutic management of BD needs to be introduced early in order to control inflammation, to preserve visual function and to limit irreversible structural damage. The aim of this review is to provide current data on how innovations in clinical evaluation, investigations and treatments were able to improve the prognosis of uveitis associated with BD.

A review of ocular adverse events of biological anti-TNF drugs

The recent introduction of biological agents has revolutionized the treatment of chronic immune-inflammatory diseases; however, this new therapy did not come without significant side effects.Through large controlled studies indicating decrease in the number of uveitis flares, the role of TNF inhibitors therapy for non-infectious uveitis gained more ground. Paradoxically to its therapeutic effect, there are reports associating these drugs with the onset or recurrence of inflammatory eye disease.A number of studies have suggested possible roles for anti-TNF-α agents in precipitating or worsening an underlying inflammatory process, including the hypothesis of a disequilibrium in cytokine balance, but to date the mechanisms responsible for these adverse events are not fully understood.A PubMed literature search was performed using the following terms: ophthalmic complication, uveitis, inflammatory eye disease, optic neuritis, neuropathy, adverse events, anti-TNF, TNF alpha inhibitor, infliximab, etanercept, adalimumab, golimumab, certolizumab, and biologics. The data presented in this study was mainly derived from the use of TNF inhibitors in rheumatology, essentially because these drugs have been used for a longer period in this medical field.Many of the ocular adverse events reported on this review may be considered a paradoxical effect of anti-TNF therapy. We found a variety of data associating new onset of uveitis with anti-TNF therapy for rheumatic conditions, predominantly under etanercept.In conclusion, although there is increasing data on ocular adverse events, it remains to be seen whether the suggested link between TNF inhibitors and the onset of ocular inflammation is substantiated by more quality data. Nevertheless, the awareness of potential treatment side effects with anti-TNF should be highlighted.

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.

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.

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.

Retinal function and morphology in the rabbit eye after intravitreal injection of the TNF alpha inhibitor adalimumab

Aim

To study the effects of the tumor necrosis factor alpha inhibitor adalimumab on rabbit retina after injection into the vitreous body.

Methods

Forty-eight rabbits of mixed strain (9–12 months old, weighing ≈ 3.5 kg) were randomized into four groups. Adalimumab was injected at one of two concentrations (1.25 mg or 2.5 mg) into the eyes of two groups, and balanced salt solution into the eyes of the third group. The fourth group acted as controls. Full-field electroretinography (ffERG) was performed before injection and 1 and 6 weeks post-injection. At 6 weeks post-injection the rabbits were euthanized and the sectioned retinas were studied. Retinal histology was studied with hematoxylin–eosin staining. Immunohistochemical analysis was performed on rods, cones, rod bipolar cells, horizontal cells, amacrine cells and Müller cells.

Results

No significant difference in ffERG amplitudes or implicit times was observed between the four groups at any time point. Histological and immunohistochemical findings were similar in all groups.

Conclusions

Injection of adalimumab into the vitreous body of healthy rabbits, at doses up to 2.5 mg, does not appear to be toxic to the rabbit retina.

Pharmacokinetics, electrophysiological, and morphological effects of the intravitreal injection of mycophenolic acid in rabbits

PURPOSE

To determine the half-life of mycophenolic acid (MPA) in the vitreous of New Zealand albino rabbits after intravitreal injection and the retinal toxicity of different doses of MPA.

METHODS

Ten micrograms of MPA (Roche Bioscience, Palo Alto, CA) was injected in the vitreous of 16 rabbits, animals were sacrificed at different time-points, and vitreous samples underwent high-performance liquid chromatography. For functional and morphological studies, 5 doses of MPA (0.05, 0.5, 2, 10, and 100 μg) were injected in the vitreous of 20 rabbits. As control, contralateral eyes were injected with aqueous vehicle. Electroretinograms (ERGs) were recorded before injection and at days 7, 15, and 30. Animals were sacrificed on day 30 and retinas were analyzed under light microscopy.

RESULTS

MPA half-life in the vitreous was 5.0±0.3 days. ERG revealed photoreceptor functional impairment in eyes injected with 0.5 μg and higher on day 30, while eyes injected with 100 μg presented the same changes already from day 15. No morphological change was found.

CONCLUSIONS

MPA vitreous half-life is 5.0 days. Intravitreal injection of 0.5 μg MPA and higher causes dose- and time-related photoreceptor sensitivity decrease in rabbits. The MPA dose of 0.05 μg may be safe for intravitreal use in rabbits.

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.

Local therapies for inflammatory eye disease in translation: past, present and future

Despite their side-effects and the advent of systemic immunosuppressives and biologics, the use of corticosteroids remains in the management of patients with uveitis, particularly when inflammation is associated with systemic disease or when bilateral ocular disease is present. The use of topical corticosteroids as local therapy for anterior uveitis is well-established, but periocular injections of corticosteroid can also be used to control mild or moderate intraocular inflammation. More recently, intraocular corticosteroids such as triamcinolone and steroid-loaded vitreal inserts and implants have been found to be effective, including in refractory cases. Additional benefits are noted when ocular inflammation is unilateral or asymmetric, when local therapy may preclude the need to increase the systemic medication.

Implants in particular have gained prominence with evidence of efficacy including both dexamethasone and fluocinolone loaded devices. However, an appealing avenue of research lies in the development of non-corticosteroid drugs in order to avoid the side-effects that limit the appeal of injected corticosteroids. Several existing drugs are being assessed, including anti-VEGF compounds such as ranibizumab and bevacizumab, anti-tumour necrosis factor alpha antibodies such as infliximab, as well as older cytotoxic medications such as methotrexate and cyclosporine, with varying degrees of success. Intravitreal sirolimus is currently undergoing phase 3 trials in uveitis and other inflammatory pathways have also been proposed as suitable therapeutic targets. Furthermore, the advent of biotechnology is seeing advances in generation of new therapeutic molecules such as high affinity binding peptides or modified high affinity or bivalent single chain Fab fragments, offering higher specificity and possibility of topical delivery.

Intravitreal tumor necrosis factor-alpha inhibitors for neovascular age-related macular degeneration suboptimally responsive to antivascular endothelial growth factor agents: a pilot study from the Pan American Collaborative Retina Study Group

PURPOSE

To compare the short-term visual and anatomic outcomes after intravitreal injections of 2 different tumor necrosis factor-α inhibitors to continued antivascular endothelial growth factor (VEGF) therapy in eyes with choroidal neovascularization (CNV) secondary to age-related macular degeneration that responded suboptimally to anti-VEGF agents.

METHODS

Retrospective comparative case series of 26 eyes. Eyes were injected intravitreally with 1 mg infliximab, 2 mg infliximab, 2 mg adalimumab, or 1.25 mg bevacizumab. The main outcomes measured were the best-corrected visual acuity (BCVA) and the central macular thickness (CMT) at 3 months of follow-up.

RESULTS

The mean log minimal angle of resolution BCVA changed from 1.04±0.23 at baseline to 1.06±0.51 at 3 months (P=0.9455) in the 1-mg infliximab group; 0.94±0.48 at baseline to 0.85±0.43 in the 2-mg infliximab group (P=0.2802); 1.58±0.50 at baseline to 1.38±0.43 in the adalimumab group (P=0.1116); and 1.08±0.1 at baseline to 1.03±0.16 in the bevacizumab group (P=0.9928). The mean CMT changed from 387±54 μm at baseline to 342±108 μm (P=0.1053) in the 1-mg infliximab group; 301±42 μm at baseline to 284±73 μm (P=0.4854) in the 2-mg infliximab group; remained unchanged at 348±106 μm (P=0.308) in the adalimumab group; and 362±66 μm to 340±27 μm in the bevacizumab group (P=0.4622). Adverse events included uveitis in 37.5% (6/16) of eyes injected with infliximab.

CONCLUSION

Intravitreal infliximab and adalimumab do not appear to benefit eyes with CNV that responded suboptimally to anti-VEGF agents. Intravitreal injections of infliximab may elicit a severe intraocular inflammatory reaction.

Review and update of intraocular therapy in noninfectious uveitis

PURPOSE OF REVIEW

To review new clinically relevant data regarding the intraocular treatment of noninfectious uveitis.

RECENT FINDINGS

Triamcinolone acetonide, the most commonly used intravitreal corticosteroid for treatment of uveitis and uveitic macular oedema has a limited duration of action and is associated with a high risk of corticosteroid-induced intraocular pressure (IOP) rise and cataract. Recent advances have led to the development of sustained-release corticosteroid devices using different corticosteroids such as dexamethasone and fluocinolone acetonide. Treatment options for patients who have previously exhibited corticosteroid hypertensive response have also expanded through the use of new noncorticosteroid intravitreal therapeutics such as methotrexate and antivascular endothelial growth factor (anti-VEGF) agents.

SUMMARY

Ozurdex dexamethasone implant appears to have a better safety profile, and a slightly long-lasting effect than triamcinolone acetonide. The Retisert implant allows the release of corticosteroids at a constant rate for 2.5 years, but it requires surgical placement and its use is associated with a very high risk of cataract and requirement for IOP-lowering surgery. For patients who are steroid responders, methotrexate may offer a better alternative to corticosteroid treatment than anti-VEGF agents, but controlled trials are required to confirm this.

intravitreal tumor necrosis factor inhibitors in the treatment of refractory diabetic macular edema: a pilot study from the Pan-American Collaborative Retina Study Group

PURPOSE

The purpose of this study was to report the short-term visual and anatomical outcomes after intravitreal injections of two different tumor necrosis factor α inhibitors in eyes with refractory diabetic macular edema.

METHODS

An interventional, retrospective, multicenter study of 39 eyes with refractory diabetic macular edema that were injected with adalimumab (n = 5 for 2 mg) or infliximab (n = 15 for 1 mg; n = 19 for 2 mg). The main outcome measures were the best-corrected visual acuity and the central macular thickness at 3 months of follow-up.

RESULTS

In the 1-mg infliximab group, the logarithm of the minimal angle of resolution best-corrected visual acuity improved from 1.49 ± 0.58 at baseline to 1.38 ± 0.56 at 3 months (P = 0.6991). In the 2-mg infliximab group, the logarithm of the minimal angle of resolution best-corrected visual acuity worsened from 0.76 ± 0.54 to 1.03 ± 0.69 at 3 months (P = 0.5995). In the adalimumab group, the logarithm of the minimal angle of resolution best-corrected visual acuity improved from 1.44 ± 0.77 to 1.08 ± 0.85 at 3 months (P = 0.2500). The central macular thickness in the 1-mg infliximab group decreased from 459 ± 125 μm at baseline to 388 ± 131 μm at 3 months (P = 0.1178). In the 2-mg infliximab group, the central macular thickness remained unchanged from 378 ± 97 μm at baseline to 349 ± 118 μm at 3 months (P = 0.2162). In the adalimumab group, the central macular thickness remained unchanged from 521 ± 163 μm at baseline to 526 ± 390 μm at 3 months (P = 0.1250). There were no systemic side effects reported in any of the patients. However, laboratory markers for autoimmunity were not done. None of the eyes injected with either adalimumab or 1 mg of infliximab had adverse ocular events. In the 2-mg infliximab group, 42% (8 of 19) of eyes developed severe uveitis. Three of these eyes (37.5%) required pars plana vitrectomy. The uveitis in the remaining five eyes resolved with topical steroid therapy.

CONCLUSION

Both intravitreal adalimumab and infliximab do not appear to benefit eyes with refractory diabetic macular edema. Intravitreal injections of infliximab may elicit a severe intraocular inflammatory reaction.

TNF-α antagonists beyond approved indications: stories of success and prospects for the future

Tumour necrosis factor alpha (TNF-α) is a key molecule of the inflammatory response and data derived from studies in experimental animal models and humans suggest that TNF-α may be implicated in the pathogenesis of various autoimmune and non-infectious inflammatory conditions. Over the past decade pharmaceutical agents directed against TNF-α (infliximab, adalimumab and etanercept) have been widely and successfully employed for the management of rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriasis, psoriatic arthritis, juvenile idiopathic arthritis and inflammatory bowel disease, whereas two novel anti-TNF-α agents, golimumab and certolimumab pegol, recently entered the market for the treatment of RA, AS, Crohn's disease and psoriasis. Encouraged by the positive results obtained from the use of TNF-α antagonists in terms of efficacy and safety and due to the increasingly accumulating evidence regarding the implication of TNF-α in the pathogenesis of numerous disorders, anti-TNF-α agents have been considered for the management of diseases other than the ones they were initially approved for. Although in the case of multiple sclerosis and chronic heart failure the outcome from the administration of TNF-α blockers had been less than favourable, in other cases of non-infectious inflammatory conditions the response to TNF-α inhibition had been fairly beneficial. More specifically, according to well-documented clinical trials, anti-TNF-α agents exhibited favourable results in Behçet's disease, non-infectious ocular inflammation, pyoderma gangrenosum and hidradenitis suppurativa. In this review we discuss the successful outcomes as well as the prospects for the future from the off-label use of TNF-α antagonists.

Harmonic analysis of the cone flicker ERG of rabbit

Harmonic analysis was used to characterize the rabbit flicker ERG elicited by sinusoidally modulated full-field stimuli under light-adapted conditions. The frequency-response function for fundamental amplitude, derived from Fourier analysis of the ERG waveforms, exhibited two limbs, with an amplitude minimum at approximately 30Hz, and a high-frequency region peaking at around 45Hz and extending to more than 100Hz at higher adapting levels. At low frequencies (<20Hz), the fundamental response amplitude was independent of mean luminance (Weber law behavior), whereas the response amplitude at high stimulus frequencies varied nonlinearly with mean luminance. At low frequencies, intravitreal administration of L-AP4, which blocks ON-pathway activity, reduced the fundamental response amplitude and produced a phase shift. On the other hand, PDA, which reduces OFF-pathway activity, had a minimal effect on both the response amplitude and phase at low frequencies. At high frequencies, L-AP4 increased the fundamental response amplitude at low mean luminances, whereas PDA had only a small effect on amplitude and phase. Both pharmacologic agents removed the minimum in the amplitude-frequency function as well as the abrupt change in phase at stimulus frequencies near 30Hz. The results suggest that there is a nonlinear interaction between ON- and OFF-pathway activity over the entire stimulus frequency range examined in this study. These findings provide a basis for formulating protocols to evaluate the effect of pharmacologic agents and/or disease on the cone flicker ERG of rabbit.

Intravitreal adalimumab for refractory uveitis-related macular edema

OBJECTIVE

To evaluate the safety and efficacy of intravitreal adalimumab injections on refractory cystoid macular edema (CME) secondary to noninfectious uveitis.

DESIGN

Prospective, noncomparative, interventional case series.

PARTICIPANTS

Eight consecutive patients with controlled uveitis and chronic, refractory CME who had failed steroid treatment.

INTERVENTION

Intravitreal adalimumab injections were given monthly for 3 months.

MAIN OUTCOME MEASURES

Mean change in central retinal thickness (CRT) on optical coherence tomography (OCT); secondary objective was the mean change in best-corrected visual acuity (BCVA).

RESULTS

Five of the eight patients completed the 6-month follow-up. For all 5 patients, the changes in BCVA from baseline to 3 months were not statistically significant (P=0.070). Similarly, the change in BCVA from baseline to 6 months was not statistically significant (P=1.0). The mean CRT at baseline was 692 microm. The changes from baseline to 3 months were not statistically significant (P=0.466); the changes from baseline to 6 months were also not statistically significant (P=0.808). We did not observe any ocular or systemic adverse effects.

CONCLUSIONS

Intravitreal adalimumab showed no efficacy in improving BCVA or reducing CRT in patients with chronic uveitic macular edema.