Update on Biologic Therapy in the Management of Axial Spondyloarthritis

Biologics in spondyloarthritis: TNFα inhibitors and other agents

TNFα inhibitors are currently the only class of biological agent that has proven to be effective in the treatment of patients with ankylosing spondylitis and/or spondyloarthritis (SpA). These agents have been shown to control inflammatory pain of the axial skeleton, peripheral clinical manifestations, certain extra-articular manifestations as well as systemic and spinal MRI inflammation. Conversely, they are unable to slow radiographic progression in the spine. Since around 20-30% of patients with SpA are considered as nonmajor responders to TNFα inhibitors, there is a need for alternative therapies. Biological agents that target IL-1, IL-6, B cells and costimulatory pathways are not effective in SpA. Conversely, novel biological agents blocking IL-23 or IL-17 are promising in SpA, especially secukinumab, an anti-IL-17A monoclonal antibody.

Responsiveness to therapy change of a global ultrasound assessment in spondyloarthritis patients

The objective of this study is to evaluate the responsiveness to therapy change of a global ultrasound (US) assessment in the short-term monitoring of spondyloarthritis (SpA) patients with peripheral involvement. Consecutive SpA patients with both clinical peripheral involvement and active disease (initiating or changing therapy) were included. All patients underwent both clinical and US assessment in day entering the study and after 3 months of follow-up. Peripheral global US assessment included the recognition of abnormal inflammatory findings at joint, tendon, and entheseal level according to standardized scanning methods. A total of 34 patients completed both basal and 3-month follow-up assessments. Acute phase reactants, both erythrocyte sedimentation rate and C-reactive protein, tenderness (68) and swollen (66) joint counts, Bath Ankylosing Spondylitis Disease Activity Index and Health Assessment Questionnaire decreased significantly at 3-month follow-up. Total score for the global US assessment also decreased significantly between basal and 3-month follow-up assessment [mean difference, 12.33 (IC 95 %, 9.23-15.42); p < 0.0001]. All individual component, joint, tendon, and enthesis scores, also showed a significant decrease during the follow-up period. A high degree of intra-observer reliability was found for the global US assessment (ICC [95 % CI]: 0.977 [0.961-0.993]). This global US assessment, including joints, tendons, and entheses, showed a good responsiveness to clinical changes and might be useful for monitoring SpA patients with peripheral involvement.

Efficacy and safety of biologic treatments in Familial Mediterranean Fever

OBJECTIVE

Colchicine is the mainstay treatment for Familial Mediterranean Fever (FMF). However 5% to 10% of the patients with FMF are unresponsive or intolerant to colchicine. Biologics are efficient in many rheumatic diseases, including rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, cryopyrin-associated periodic syndromes. We performed a systematic review to analyze patients with FMF, including juvenile patients who received treatment with biologics.

METHODS

A MEDLINE search, including articles published in English language between 1990 and May 2012, was performed. Patients who had Mediterranean fever variants but could not be classified as FMF according to Tel-Hashomer criteria were excluded.

RESULTS

There is no controlled trial on the efficacy and safety of biologics in FMF. Fifty-nine (32 female and 27 male) patients with FMF who had been treated with biologics (infliximab, etanercept, adalimumab, anakinra, and canakinumab) were reported in 24 single reports and 7 case series. There were 16 children and 43 adults (7- to 68-year olds). Five patients were reported to have colchicine intolerance or had adverse events related to colchicine use, and the rest 54 were unresponsive to colchicine treatment.

CONCLUSIONS

The current data are limited to case reports, and it is difficult to obtain a quantitative evaluation of response to biologic treatments. However, on the basis of reported cases, biologic agents seem to be an alternative treatment for patients with FMF who are unresponsive or intolerant to colchicine therapy and seem to be safe. Controlled studies are needed to better evaluate the safety and efficacy of biologics in the treatment of patients with FMF.

Duration of remission after halving of the etanercept dose in patients with ankylosing spondylitis: a randomized, prospective, long-term, follow-up study

Background

The aim of this study was to evaluate the proportion of patients with ankylosing spondylitis maintaining clinical remission after reduction of their subcutaneous etanercept dose to 50 mg every other week compared with that in patients receiving etanercept 50 mg weekly.

Methods

In the first phase of this randomized, prospective, follow-up study, all biologic-naïve patients identified between January 2005 and December 2009 as satisfying the modified New York clinical criteria for ankylosing spondylitis treated with etanercept 50 mg weekly were evaluated for disease remission in January 2010. In the second phase, patients meeting the criteria for remission were randomized to receive subcutaneous etanercept as either 50 mg weekly or 50 mg every other week. The randomization allocation was 1:1. Remission was defined as Bath Ankylosing Spondylitis Disease Activity Index < 4, no extra-axial manifestations of peripheral arthritis, dactylitis, tenosynovitis, or iridocyclitis, and normal acute-phase reactants. The patients were assessed at baseline, at weeks 4 and 12, and every 12 weeks thereafter. The last visit constituted the end of the follow-up.

Results

During the first phase, 78 patients with ankylosing spondylitis (57 males and 21 females, median age 38 years, median disease duration 12 years) were recruited. In January 2010, after a mean follow-up of 25 ± 11 months, 43 (55.1%) patients achieving clinical remission were randomized to one of the two treatment arms. Twenty-two patients received etanercept 50 mg every other week (group 1) and 21 received etanercept 50 mg weekly (group 2). At the end of follow-up, 19 of 22 (86.3%) subjects in group 1 and 19 of 21 (90.4%) in group 2 were still in remission, with no significant difference between the two groups. The mean follow-up duration in group 1 and group 2 was 22 ± 1 months and 21 ± 1.6 months, respectively.

Conclusion

Remission of ankylosing spondylitis is possible in at least 50% of patients treated with etanercept 50 mg weekly. After halving of the etanercept dose, remission is maintained in a high percentage of patients during long-term follow-up, with important economic implications.

Treatment of ankylosing spondylitis: a critical appraisal of nonsteroidal anti-inflammatory drugs and corticosteroids

Treatment of ankylosing spondylitis and related disorders has been revolutionized by the advent of biological therapy, especially tumor necrosis factor-α inhibitors. Nonsteroidal anti-inflammatory drugs, however, remain the first line of treatment. Evidence has accumulated that nonsteroidal anti-inflammatory drug therapy of ankylosing spondylitis and related disorders is effective in controlling several of the clinical manifestations seen in these disorders, particularly pain, physical function and perhaps progressive spinal fusion. What needs to be proven, however, is the long-term safety profile of these drugs.

Current therapeutics for spondyloarthritis

INTRODUCTION

Ankylosing spondylitis (AS) belongs to a clinically related group of disorders named spondyloarthritis (SpA) that mainly affect the axial skeleton and present with specific extra-articular manifestations. The therapeutic management of AS and other SpA has considerably progressed over the past 10 years.

AREAS COVERED

This paper provides a review of the available treatments for AS including traditional treatments (NSAIDs, sulfasalazine and methotrexate, local corticosteroids) and biological therapies (TNF-α antagonists), as well as nonpharmacological procedures (education and physical therapy) and specific recommendations for this therapeutic management.

EXPERT OPINION

NSAIDs remain the first-line treatment in patients with AS, especially with axial disease. There is an increasing amount of evidence showing the short-term and long-term efficacy of TNF-α antagonists in AS, with the control of pain, extra-articular manifestations and spinal inflammation as evidenced by MRI. By contrast, there is no proof for the control of radiographic progression at the spine with these agents. An early diagnosis is now possible using the new classification criteria for SpA. However, it remains to be established if an early intervention might control the progression of the disease. Since about 20 - 25% of patients are considered as nonmajor responders to TNF-α blockers, there is an unmet need for developing new biological therapies. Targeting the IL-17 pathway may be an interesting option. International recommendations for the management of AS by the Assessment of Spondyloarthritis (ASAS) group were recently updated and discussed the respective place of each current therapeutic option in AS.

Ankylosing spondylitis macrophage production of higher levels of interleukin-23 in response to lipopolysaccharide without induction of a significant unfolded protein response

OBJECTIVE

Previous studies of the HLA-B27-transgenic rat model of ankylosing spondylitis (AS) suggested that macrophages develop an intracellular stress response called the unfolded protein response (UPR) and, as a result, secrete increased amounts of cytokines in response to Toll-like receptor agonists such as lipopolysaccharide (LPS). Our objective was to determine whether macrophages from AS patients also undergo a UPR and secrete increased cytokines/chemokines in response to LPS.

METHODS

Peripheral blood monocytes isolated from 10 AS patients and 10 healthy controls were differentiated in vitro with macrophage colony-stimulating factor. Select samples were treated with interferon-γ (IFNγ) to up-regulate class I major histocompatibility complex (HLA-B) expression prior to stimulation with LPS for either 3 hours (for RNA) or 8-24 hours (for supernatant). UPR induction was assessed by measuring the expression of messenger RNA for ERdj4, BiP, and CCAAT/enhancer binding protein homologous protein 10 (CHOP).

RESULTS

Although IFNγ treatment up-regulated HLA-B expression (2-fold; P < 0.0001), neither IFNγ nor LPS substantially enhanced BiP or CHOP expression (<1.3-fold). ERdj4 expression increased weakly, but not significantly, in AS samples treated with IFNγ plus LPS (2.2-fold; P = 0.31). In response to LPS, AS macrophages secreted more CXCL9, interleukin-10 (IL-10), IL-12p70, IL-23, and tumor necrosis factor α than did control macrophages (P ≤ 0.025). The most striking difference was observed for IL-23 (median 265 pg/ml in AS patients versus 9 pg/ml in controls; P = 0.0007). We did not detect significant differences in IL-6, IL-8, or IFNβ production.

CONCLUSION

The greater production of IL-23 by AS patient macrophages in response to LPS provides further support for the development of Th17/IL-23-directed therapy. Since significant UPR induction was not detected in AS patient macrophages, the relationship between UPR and inflammatory cytokine production remains unclear.

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.