Experience with infliximab (anti-TNF alpha monoclonal antibody) as monotherapy for giant cell arteritis

Unmet Needs in the Pathogenesis and Treatment of Vasculitides

Despite the progress in the last years on the field of vasculitides, there are several unmet needs regarding classification, disease activity assessment, predictors of flares and complications, and type of treatment for the different forms. The 1990 American College of Rheumatology (ACR) classification criteria currently used to define giant cell arteritis and Takayasu arteritis were designed to discriminate between different types of vasculitides but not to differentiate vasculitis from other disorders. Recently, efforts have been made to overcome the shortcomings of the ACR criteria. The lack of an accepted definition of disease activity in large-vessel vasculitides presents a major challenge in creating useful and valid outcome tools for the assessment of disease course. Identification of predictors of flares can aid in optimizing therapeutic strategies, minimizing disease flares, and reducing treatment-related side effects. It is furthermore important to recognize and characterize the risk factor that might predict the manifestations associated with poor outcome and prognosis. Two RCTs have evidenced the efficacy of tocilizumab in addition to glucocorticoids (GCs) in the treatment of giant cell arteritis (GCA). However, the role of tocilizumab or other biological agents without GCs needs to be investigated. Recent observational studies have suggested that rituximab is also effective in patients with eosinophilic granulomatosis with polyangiitis and in antineutrophil cytoplasmic antibodies (ANCA)-negative patients with granulomatosis with polyangiitis and microscopic polyangiitis. Rituximab or anti-TNF alfa may represent a possible alternative therapy in case of refractory or difficult to treat polyarteritis nodosa (PAN) patients. The new International Criteria for Behçet's Disease have shown a better sensitivity and a better accuracy compared to the older International Study Group on Behçet's Disease criteria. The EULAR recommendations for the management of Behçet's disease (BD) have been recently updated. However, the treatment of refractory disease is still a real challenge.

Standard and biological treatment in large vessel vasculitis: guidelines and current approaches

INTRODUCTION

Giant cell arteritis and Takayasu arteritis are the two major forms of idiopathic large vessel vasculitis. High doses of glucocorticoids are effective in inducing remission in both conditions, but relapses and recurrences are common, requiring prolonged glucocorticoid treatment with the risk of the related adverse events. Areas covered: In this article, we will review the standard and biological treatment strategies in large vessel vasculitis, and we will focus on the current approaches to these diseases. Expert commentary: The results of treatment trials with conventional immunosuppressive agents such as methotrexate, azathioprine, mycophenolate mofetil, and cyclophosphamide have overall been disappointing. TNF-α blockers are ineffective in giant cell arteritis, while observational evidence and a phase 2 randomized trial support the use of tocilizumab in relapsing giant cell arteritis. Observational evidence strongly supports the use of anti-TNF-α agents and tocilizumab in Takayasu patients with relapsing disease. However biological agents are not curative, and relapses remain common.

The role of biological agents in the management of large vessel vasculitis (LVV): a systematic review and meta-analysis

BACKGROUND

Giant cell arteritis (GCA) and Takayasu's arteritis (TAA) are large vessel vasculitides (LVV) for which corticosteroids (CS) are the mainstay for treatment. In patients with LVV unable to tolerate CS, biological agents have been used with variable effectiveness.

OBJECTIVE

To systematically review the effectiveness and safety of biological agents in patients with LVV.

METHODS

We searched 5 electronic databases (inception to October 2012) and conference abstracts with no language restrictions. Two reviewers independently selected studies, extracted data and assessed methodological quality. Our protocol was registered in PROSPERO.

RESULTS

We included 25 studies (3 RCTs and 22 case series with ≥2 cases). 95 GCA and 98 TAA patients received biological agents. The RCTs using anti-TNF agents (infliximab, etanercept and adalimumab) did not suggest a benefit in GCA. GCA patients receiving tocilizumab, in case series, achieved remission (19 patients) and reduction of corticosteroid dose (mean difference, -16.55 mg/day (95% CI: -26.24, -6.86)). In case series, 75 patients with refractory TAA treated with infliximab discontinued CS 32% of the time. Remission was variably defined and the studies were clinically heterogeneous which precluded further analysis.

CONCLUSION

This systematic review demonstrated a weak evidence base on which to assess the effectiveness of biological treatment in LVV. Evidence from RCTs suggests that anti-TNF agents are not effective for remission or reduction of CS use. Tocilizumab and infliximab may be effective in the management of LVV and refractory TAA, respectively, although the evidence comes from case series. Future analytical studies are needed to confirm these findings.

Polymyalgia rheumatica and giant cell arteritis in older patients: diagnosis and pharmacological management

Giant cell arteritis (GCA) is an inflammatory vasculopathy that involves large- and medium-sized arteries and can cause vision loss, stroke and aneurysms. GCA occurs in people aged >50 years and is more common in women. A higher incidence of the disease is observed in populations from Northern European countries. Polymyalgia rheumatica (PMR) is a periarticular inflammatory process manifesting as pain and stiffness in the neck, shoulders and pelvic girdle. PMR shares the same pattern of age and sex distribution as GCA. The pathophysiology of PMR and GCA is not completely understood, but the two conditions may be related and often occur concurrently. A delay in the diagnosis should be avoided because of the risk of vascular ischaemic complications due to GCA. The diagnosis should be considered in patients aged >50 years presenting with symptoms such as new headache, visual disturbances, jaw claudication or symptoms of PMR. GCA can also present as a systemic inflammatory syndrome with fever of unknown origin. Marked elevation of acute-phase reactants, recognizable in higher erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels, is often seen in both PMR and GCA. However, some patients can present with a normal ESR. Confirmation of the diagnosis of GCA by temporal artery biopsy is important because clinical findings and laboratory tests are not specific, and because a diagnosis of GCA commits patients to long-term treatment with corticosteroids. The role of imaging techniques for the diagnosis of GCA remains unclear, but these modalities can be helpful in assessing the extent of vascular involvement, especially when extra-cranial disease is present. In PMR, subdeltoid and subacromial bursitis can be identified by imaging techniques, especially ultrasound or MRI. The clinical manifestations of GCA and PMR respond dramatically within 12-48 hours of starting corticosteroid treatment. The initial corticosteroid dosage commonly used in GCA is oral prednisone 40-60 mg/day, and for patients with PMR a dosage of 15-20 mg/day is often sufficient. A prolonged course of treatment is necessary, and corticosteroids are gradually tapered, guided by regular clinical evaluation and ESR (and/or CRP) measurement. Methotrexate is the best studied corticosteroid-sparing agent in GCA, and may be useful for patients with frequent disease relapses and/or corticosteroid-related toxicity. Retrospective studies favour aspirin (acetylsalicylic acid) as an effective adjuvant treatment for reducing the ischaemic complications of GCA. The long-term course of corticosteroid therapy frequently exposes elderly patients with PMR/GCA to various adverse effects, which can be attenuated with appropriate prophylactic measures. Co-morbid diseases and polypharmacy can pose particular challenges in the geriatric population. In general, the life expectancy of patients with GCA does not appear to be shortened, whereas the morbidity associated with the disease and its treatment is well recognized.

New indications for biological therapies

Biological agents have originally been developed to treat refractory arthritis, but evidence has been accruing, supporting their use in vasculitis as well. In the large-vessel vasculitides giant cell arteritis and Takayasu arteritis, TNF-α inhibitors have shown some efficacy in patients with relapsing disease. In contrast, in patients with recent onset of giant cell arteritis, TNF-α inhibitors failed to provide a significant benefit over and above that conferred by glucocorticoids alone. More recent, preliminary data suggest a role for the interleukin-6 receptor antagonist tocilizumab in both resistant and treatment-naïve giant cell arteritis and Takayasu arteritis. Biological agents have also been proposed to treat difficult anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis. Uncontrolled observations suggest that the TNF-α inhibitor infliximab might be beneficial in resistant cases. On the contrary, a randomized controlled trial did not show superiority of the recombinant human soluble TNF-α p75 receptor fusion protein etanercept over placebo in maintaining remission in granulomatosis with polyangiitis. Two randomized controlled trials have demonstrated that the anti-CD20 monoclonal antibody rituximab was as effective as the standard-of-care agent cyclophosphamide in inducing remission. In addition, rituximab appeared to be superior to cyclophosphamide in inducing remission in the subset of patients with relapsing disease. These findings prove that biological therapy has a role in vasculitis. Research is investigating novel therapies as well as focusing on how to best use the available drugs.

Tumor necrosis factor biologics beyond psoriasis in dermatology

INTRODUCTION

TNF-α is a cytokine essential for immune response and its receptors has been shown to be dysregulated in a variety of diseases including psoriasis vulgaris. There are a number of TNF-α inhibitors approved for psoriasis, however there is a growing body of literature supporting their use in a wide variety of dermatological conditions.

AREAS COVERED

The use of biologic TNF-α antagonists in conditions for which they have not yet been approved by the FDA ('off-label' uses) and the literature that supports the most appropriate agents and conditions for use. A PubMed/MEDLINE search was performed with the keywords 'TNFα antagonist', 'biologic therapy', 'off-label' and 'unapproved'. The list of references and citing articles of the articles retrieved were also used as sources. This complete list was evaluated for inclusion, based on relevance to the proposed goal of this review.

EXPERT OPINION

There are a large number of conditions for which biologic antagonists of TNFα are effective, beyond those already approved by the FDA. The various agents vary in their efficacy in treatment, with infliximab consistently the most effective, particularly in granulomatous diseases. Although effectiveness varies among these conditions, biologic antagonists of TNF-α are promising for the treatment of these diseases.

Biologic agents in systemic vasculitis

The treatment of systemic necrotizing vasculitis has made great strides in both efficacy and outcomes. Standard therapies, however, are associated with numerous side effects, and not all patients will respond to conventional immunosuppression. These realities have prompted the search for safer and more efficacious treatments, most notably among biologic agents. For example, the role of TNF-α in the pathophysiology of several vasculitides has led to the investigation of targeted inhibitors of this cytokine, albeit with mixed results. There have been some disappointing results in the area of giant cell arteritis and Wegener's granulomatosis (granulomatosis with polygiitis), but anti-TNF therapy has shown promise in the treatment of Takayasu's arteritis, although additional trials to demonstrate its efficacy are required. Anti-B-cell therapy seems to be the most promising advance in the management of these diseases. Complete and partial responses have been seen in both primary and secondary mixed cryoglobulinemic vasculitis. Recent trials have demonstrated that rituximab is effective for the treatment of Wegener's granulomatosis and microscopic polyangiitis. These trials have, however, raised concerns regarding the long-term safety of these agents. The future holds promise for additional targeted therapies with improved patient response and fewer side effects.

Effect of etanercept in polymyalgia rheumatica: a randomized controlled trial

Introduction

To elucidate in polymyalgia rheumatica (PMR) the role of tumor necrosis factor (TNF) α and the therapeutic potential of blockade with soluble TNF-α receptor, we carried out the first randomized controlled trial with etanercept in PMR.

Methods

Twenty newly diagnosed, glucocorticoid (GC) naïve patients with PMR and 20 matched non-PMR control subjects completed the trial. Subjects were randomized in a 1:1 ratio to monotherapy with etanercept (25 mg s.c. biweekly) or placebo (saline) for 14 days. Study outcomes were assessed at baseline and after 14 days. The primary outcome was the change in PMR activity score (PMR-AS). Secondary outcomes were: changes in erythrocyte sedimentation rate (ESR) and plasma levels of TNF-α and interleukin (IL) 6; patients' functional status (health assessment questionnaire) and cumulative tramadol intake during the trial.

Results

At baseline, plasma TNF-α was higher in patients than in controls (P < 0.05). The concentration always increased with etanercept treatment (P < 0.05). In patients, etanercept decreased PMR-AS by 24% (P = 0.011), reflecting significant improvements in shoulder mobility, physician's global assessment and C-reactive protein, and insignificant (P > 0.05) improvements in duration of morning stiffness and patient's assessment of pain. In parallel, ESR and IL-6 were reduced (P < 0.05). Placebo treatment did not change PMR-AS, ESR and IL-6 (P > 0.05). Functional status did not change and tramadol intake did not differ between patient groups. In controls, no changes occurred in both groups.

Conclusions

Etanercept monotherapy ameliorates disease activity in GC naïve patients with PMR. However, the effect is modest, indicating a minor role of TNF-α in PMR.

Trial registration

ClinicalTrials.gov (NCT00524381).

Temporal arteritis with scalp ulceration and blindness

Temporal arteritis or giant cell arteritis is a systemic granulomatous vasculitis of medium and large-sized arteries, most frequently involving the temporal artery. It presents with headache, fever, elevated erythrocyte sedimentation rate and anemia. If untreated, complications like ischemic optic neuritis may even lead to blindness. Although very rare, scalp necrosis and ulcerations are the most common dermatologic findings. An 85-year-old woman presented with a two-month history of bilateral scalp ulcerations, followed by permanent loss of vision in the left eye due to the delay in diagnosing temporal arteritis.

[Systematic review on the use of adalimumab in autoinmune. Efficacy and safety in 54 patients]

OBJECTIVE

To analyze published evidence about adalimumab use in autoimmune diseases.

METHODS

Systematic review of MEDLINE database of citations included from January 1990 to December 2008 employing the terms "adalimumab" and the different systemic autoimmune diseases.

RESULTS

Our search identified 241 potentially relevant citations. 154 were retrieved for detailed evaluation. Finally, 18 were selected as relevant, including 54 patients. The reported diseases were as follow: Behçet disease in 16 patients, idiopathic uveitis in 13, sarcoidosis in 5, uveitis associated with rheumatologic diseases in 5 (psoriasis in 2, ankylosing spondylitis in 1, juvenile idiopathic arthritis in 1, Crohn disease in 1), Vogt-Koyanagi-Harada disease in 4, Birdshot uveitis in 4, vasculitis in 3 (1 temporal arteritis, 1 Takayasu's disease, 1 skin vasculitis associated with rheumatoid arthritis), adult onset Still disease in 2, relapsing polychondritis in 1 and systemic sclerosis in 1. The clinical spectrum included uveitis (39 cases), skin and/or mucosae (9), vasculitis (3), arthritis (6), lung (3). These patients were refractory to standard therapy, including corticosteroids (42 cases, 78%), immunosuppressants (42, 78%) and biologics (29, 54%). Fifty (93%) patients responded to adalimumab. The clinical response was similar in those patients who had been treated with other biologic and in those who had not received biologic therapy before adalimumab. The patients were followed for 11.9 months. Twelve (22%) patients relapsed. Five (9%) patients suffer some side effect (3 local skin reaction, 1 angioedema, 1 lung fibrosis). One patient (2%) died due to progression of her disease.

CONCLUSIONS

Available data about the use of adalimumab in autoinmune diseases come from case reports and uncontrolled studies, that include patients with severe disease and refractory to standard therapy. In this setting, it seems to be an effective and safe treatment option, especially in patients with uveitis and Behçet's disease. This initial data must be confirmed by controlled assays before extending adalimumab use.

[Anti-TNFalpha therapy in systemic autoimmune and/or inflammatory diseases]

TNFalpha plays a crucial role in the physiopathology of a large number of auto-immune and/or inflammatory systemic diseases. In addition to authorized indications including rheumatoid arthritis, ankylosing spondylitis, Crohn disease, ulcerative colitis, psoriatic arthritis and plaque psoriasis, TNFalpha blockers have been tested in a wide range of auto-immune and/or inflammatory diseases. TNFalpha blockers might be an option in refractory ANCA-associated vasculitis, sarcoïdosis, adult onset Still disease, Behçet disease, AA amyloïdosis and TRAPS. However, pertaining to the limited number of prospective randomized trails available, the small number of patients included and the poor methodology, it is difficult to define their place in the therapeutic strategy in these conditions. The therapeutic effect of TNFalpha blockers is often suspensive and disease flares are frequently observed during sustained treatment, as in the case of Behçet's disease. Published data do not support the use of TNFalpha blockers in connective tissue diseases.

Advances in the use of biologic agents for the treatment of systemic vasculitis

PURPOSE OF REVIEW

Due to the well known toxicities of cyclophosphamide, substantial interest exists in finding other therapies to treat primary systemic vasculitis. Biologic agents have been proposed as an alternative to cyclophosphamide for these disorders because of their recent success in treating other rheumatic diseases. This article reviews the current state-of-the-art therapy with regards to the use of biologic agents as treatments for systemic vasculitis.

RECENT FINDINGS

The greatest amount of experience with these agents for the treatment of systemic vasculitis is with antitumor necrosis factor agents, pooled intravenous immunoglobulin, and anti-B-cell therapies such as rituximab. Intravenous immunoglobulin is already a standard therapy for Kawasaki's disease, but should also be considered for the treatment of vasculitis associated with antineutrophil cytoplasmic antibodies when standard therapies are either ineffective or contraindicated. Early experience with tumor necrosis factor inhibitors indicates that they may be effective for the treatment of Takayasu's arteritis, but their role in the treatment of other forms of vasculitis remains controversial. Early experience with rituximab for the treatment of several forms of vasculitis has been quite promising, but must be confirmed by ongoing randomized clinical trials.

SUMMARY

Biologic agents represent the next evolution in treatment for the primary systemic vasculitides. Greater understanding of these diseases has allowed us to move further away from nonspecific, highly toxic therapies toward a more directed approach. As our experience with these agents increases, they will likely form the keystone of treatment in the near future.

Giant cell arteritis: an updated review

Giant cell arteritis (GCA) is the most common primary vasculitis of adults. The incidence of this disease is practically nil in the population under the age of 50 years, then rises dramatically with each passing decade. The median age of onset of the disease is about 75 years. As the ageing population expands, it is increasingly important for ophthalmologists to be familiar with GCA and its various manifestations, ophthalmic and non-ophthalmic. A heightened awareness of this condition can avoid delays in diagnosis and treatment. It is well known that prompt initiation of steroids remains the most effective means for preventing potentially devastating ischaemic complications. This review summarizes the current concepts regarding the immunopathogenetic pathways that lead to arteritis and the major phenotypic subtypes of GCA with emphasis on large vessel vasculitis, novel modalities for disease detection and investigative trials using alternative, non-steroid therapies.

Neuro-ophthalmic complications in giant cell arteritis

Giant cell arteritis (GCA) is a medical emergency characterized by systemic inflammation and critical ischemia. Neuro-ophthalmic complications occur early, with permanent vision loss in up to one fifth of patients. This mainly results from failure of prompt recognition and treatment. Diagnosis of GCA is often preceded by unrecognized symptoms, including constitutional upset and jaw claudication. Features predictive of permanent visual loss include jaw claudication and temporal artery abnormalities on physical examination. These patients often do not mount high inflammatory responses. Modern imaging techniques show diagnostic promise, and have led to an increased recognition of major artery involvement in GCA. However, temporal artery biopsy remains the gold standard for investigation. Intimal hyperplasia on histologic examination is associated with neuro-ophthalmic complications. The mainstay of therapy remains corticosteroids. Experience using conventional disease-modifying drugs has been mixed, and biologic therapies require further evaluation for their steroid-sparing potential.

Drug insight: anti-tumor necrosis factor therapies for the vasculitic diseases

The introduction of targeted biologic agents directed against tumor necrosis factor (TNF) has represented a novel and exciting avenue for investigation into therapies for the vasculitic diseases. In vasculitic diseases that are associated with granuloma formation, anti-TNF agents are a particularly attractive approach to treatment in that their mechanism of action targets immunologic pathways that are thought to have a role in disease pathogenesis. To date, a number of important trials have investigated the use of anti-TNF agents in patients with a vasculitic disease: most notably, Wegener's granulomatosis, giant-cell arteritis, Takayasu's arteritis, and Behçet's disease. Randomized, placebo-controlled trials of anti-TNF therapies for vasculitic diseases have advanced our knowledge not only in terms of their clinical results but also by demonstrating that networks of researchers can conduct multicenter trials in these uncommon diseases. Experience with the use of anti-TNF agents in patients with Wegener's granulomatosis or giant-cell arteritis has emphasized the crucial role of randomized trials in determining whether a treatment is effective, even in the face of promising preliminary data. Caution is necessary in clinical practice until such data become available.

Improving therapeutic options for patients with giant cell arteritis

PURPOSE OF REVIEW

Glucocorticoids remain the mainstay of treatment of giant cell arteritis. The aim of this review is to establish the optimal schedule of glucocorticoid administration, and to ascertain which other treatments may be used as glucocorticoid-sparing agents.

RECENT FINDINGS

An initial dose of 40-60 mg/day of prednisone is usually adequate. Patients at risk of developing ischemic complications require dosages of around 1 mg/kg/day, whereas pulse glucocorticoid therapy is no more effective in preventing ischemic complications. In patients with longstanding disease or those at risk for glucocorticoid-related adverse events, methotrexate or azathioprine can be used as glucocorticoid-sparing drugs. Infliximab has been demonstrated to be efficacious in glucocorticoid-resistant disease in an open study, whereas a randomized controlled trial showed no efficacy in patients with recent-onset disease. Finally, two retrospective studies suggest that low-dose aspirin may decrease the rate of cranial ischemic complications secondary to giant cell arteritis.

SUMMARY

Glucocorticoids remain the cornerstone of therapy for giant cell arteritis. To achieve maximal efficacy but minimize glucocorticoid-related adverse reactions, dosage should be individually tailored. In patients with longstanding, recalcitrant disease, methotrexate, azathioprine or tumor necrosis factor-alpha inhibitors may be considered. Aspirin is recommended in all patients unless contraindicated. Osteoporosis prophylaxis should also be regularly implemented.

Potential target of infliximab in autoimmune and inflammatory diseases

Tumour necrosis factor-alpha (TNF-alpha) is a pro-inflammatory cytokine produced by many cell types (blood monocytes, macrophages, mast cells and endothelial cells), that play a key role in the pathogenesis of multiple autoimmune and nonautoimmune disorders. A number of large placebo-controlled trials have shown that infliximab, a chimeric monoclonal antibody against TNF-alpha, is effective and well tolerated in patients with Crohn's disease, rheumatoid arthritis and spondiloarthritides and has become a widely used treatment for these diseases. Preliminary data suggest that several forms of vasculitis appear responsive to TNF antagonists: Behçet's disease, Churg-Strauss vasculitis, polyarteritis nodosa, and giant cell arteritis, among others. Wegener's granulomatosis and sarcoidosis have been shown to improve with infliximab. Polymyositis/dermatomyositis may also be responsive to TNF blockade. TNF likely plays little role in Sjögren's syndrome as evidenced by the lack of efficacy of TNF antagonists. There is a rationale for using TNF blockade even in systemic lupus erythematosus, a prototype of autoantibody-mediated disease, and a pilot study seems to confirm this potential effective approach. A number of other more rare disorders also may be responsive to TNF blockade. We here review the current and prospective roles of infliximab in the treatment of autoimmune diseases and other conditions.

Off-label uses of biologics in dermatology: Rituximab, omalizumab, infliximab, etanercept, adalimumab, efalizumab, and alefacept (Part 2 of 2)

Recently, dermatologists have witnessed a revolution in our therapeutic armamentarium with the development of several novel biologic immunomodulators. Although psoriasis remains the only condition in dermatology for which the use of biologic immunomodulators has been approved by the Food and Drug Administration, these drugs have the potential to significantly impact the treatment of several inflammatory conditions in dermatology. This article includes a review of the mechanism of action, dosing, and side-effect profile, as well as a review of the current literature on off-label uses of the CD20-positive B-cell antagonist rituximab, the IgE antagonist omalizumab, the tumor necrosis factor-alpha antagonists infliximab, etanercept, and adalimumab, and the T-cell response modifiers efalizumab and alefacept.

Treatment of refractory temporal arteritis with adalimumab

High-dose corticosteroids (CS) are the mainstay of treatment for temporal (giant cell) arteritis (TA). A usually required long-term treatment with CS, ranging from 1 to 5 years or more, frequently leads to serious side effects in about 60% of patients. There is no conclusive evidence about the role of immunosuppressive agents like methotrexate and azathioprine in the treatment of TA. There are few reports of treatment of refractory or steroid-dependent TA with tumor necrosis factor alpha (TNF-alpha) inhibitors including infliximab and etanercept. TA is characterized by infiltration of the vessel wall by macrophages, giant cells, and T lymphocytes, with production of several cytokines responsible for the acute phase response. TNF-alpha has been demonstrated in up to 60% of the cells in all areas of inflamed arteries by immunohistochemical techniques; hence, it could play a pivotal role in the pathogenesis of TA. We report the first case of resistant TA, which was treated successfully with adalimumab, a fully human recombinant IgG1, anti-TNF-alpha monoclonal antibody. The efficacy of TNF-alpha inhibitors in resistant TA should be studied in larger, controlled studies.

Novel therapeutic strategies for large vessel vasculitis

Giant cell arteritis and Takayasu's arteritis are systemic vasculitides that cause inflammation of large arteries and their branches. Both have similar histology, but differ in their age of onset. Corticosteroids have been the mainstay of treatment for the past 50 years but are limited by the potential toxicity that may occur in almost 60% of patients. This limitation has lead to the investigation of alternative agents for the treatment of these diseases.

Newer Therapeutic Approaches to the Vasculitides: Biologic Agents

Biologic therapies have emerged as important treatments in chronic inflammatory diseases, such as rheumatoid arthritis and inflammatory bowel disease, and are now garnering more attention in the vasculitides. These agents, including tumor necrosis factor-alpha inhibitors, B-cell-depleting agents, interferon-alpha, and some antiviral treatments, target specific components of the immune system and may have lower side effect risk profiles than the conventional immunosuppressives and cytotoxic agents. This article addresses the encouraging data and the possible pitfalls of these new therapeutic options, thus far evaluated mostly by case reports, small series, and open-label trials. Confirming the efficacy of existing and newer therapies will require further clinical investigation through randomized placebo-controlled studies to identify the proper doses and treatment schedules and single out those drugs that may expose patients to dangers that outweigh the potential benefits.

Horton’s disease: Past and present

Although the disease known as temporal arteritis, giant cell arteritis, and Horton's disease has been known since at least the 10th century, Hutchinson (1890) and Horton (1932) characterized the condition in the more recent medical literature. The diagnosis of this potentially serious illness can be surprisingly elusive, and treatment is fraught with some frustrating pitfalls. For the most part, careful evaluation of patients (usually elderly) with the typical presentation of head pain and constitutional signs yields prompt diagnosis. Treatment with corticosteroids, the standard since the mid-1950s, is usually very successful in relieving pain and tenderness and in preventing visual and other sequelae. This article discusses the evolution of medical understanding of the disease, pathophysiology, diagnosis, and modern treatment options.

The utility of tumour necrosis factor blockade in orphan diseases

A variety of rheumatic disorders have been successfully treated with tumour necrosis factor (TNF) blockers. However, TNF blockade may be useful in a number of rare diseases. Preliminary data suggest that several forms of vasculitis appear responsive to TNF antagonists-Behcet's disease, Churg-Strauss vasculitis, polyarteritis nodosa, and giant cell arteritis, among others. Wegener's granulomatosis and sarcoidosis have been shown to improve with infliximab but not with etanercept. These results lend further support for the concept of differential mechanism(s) of action of the two antagonists with infliximab being more effective for the treatment of granulomatous diseases. Polymyositis/dermatomyositis may also be responsive to TNF blockade. TNF likely plays little role in Sjogren's syndrome as evidenced by the lack of efficacy of both TNF antagonists. Etanercept has been shown to be useful in the treatment of hepatitis C both in reducing the viral load and improving liver function. A number of other more rare disorders also may be responsive to TNF blockade. Further studies with larger numbers of well characterised patients and treatment regimens are necessary to provide more definitive evidence of the utility of the TNF antagonists in these serious and often life threatening diseases.

Headache caused by giant cell arteritis

Giant cell arteritis (GCA) is the most common primary systemic vasculitis in older adults. Patients usually are older than 50 years and have an erythrocyte sedimentation rate (Westergren) greater than 50 mm/h. Headache is a common symptom, occurring in approximately 90% of patients. However, the most serious complications of GCA, blindness and stroke, may occur in the absence of headache. Nonspecific constitutional symptoms such as weight loss, fever, and malaise may dominate the clinical presentation. Currently, corticosteroids are the mainstay of therapy for GCA. Treatment is initiated at 0.7 to 1 mg/kg mg of prednisone (or equivalent) per day as soon as the diagnosis is suspected. The medication is tapered based on laboratory parameters and symptoms. Relapse is common, especially during the first year of therapy. Side effects from steroids in the elderly are common and often serious. Steroid resistance (manifesting as continued high dose requirements after 3 to 6 months) may complicate therapy and place patients at increased risk of side effects. Methotrexate and azathioprine have been used as steroid-sparing agents based on anecdotal evidence. More recently, evidence is emerging that antitumor necrosis factor-alpha agents may be efficacious and act as steroid-sparing agents. New-onset headache or worsening headache in a patient older than 50 years should raise the possibility of GCA and appropriate therapeutic and diagnostic measures should be begun promptly.