Efficacy and safety of upadacitinib for active ankylosing spondylitis refractory to biological therapy: a double-blind, randomised, placebo-controlled phase 3 trial.

OBJECTIVES: To evaluate the efficacy and safety of upadacitinib, a Janus kinase inhibitor, in patients with active ankylosing spondylitis (AS) with an inadequate response (IR) to biological disease-modifying antirheumatic drugs (bDMARDs). METHODS: Adults with active AS who met modified New York criteria and had an IR to one or two bDMARDs (tumour necrosis factor or interleukin-17 inhibitors) were randomised 1:1 to oral upadacitinib 15 mg once daily or placebo. The primary endpoint was Assessment of SpondyloArthritis international Society 40 (ASAS40) response at week 14. Sequentially tested secondary endpoints included Ankylosing Spondylitis Disease Activity score, Spondyloarthritis Research Consortium of Canada MRI spine inflammation score, total back pain, nocturnal back pain, Bath Ankylosing Spondylitis Functional Index, Bath Ankylosing Spondylitis Metrology Index and Maastricht Ankylosing Spondylitis Enthesitis Score. Results are reported from the 14-week double-blind treatment period. RESULTS: A total of 420 patients with active AS were randomised (upadacitinib 15 mg, n=211; placebo, n=209). Significantly more patients achieved the primary endpoint of ASAS40 at week 14 with upadacitinib vs placebo (45% vs 18%; p<0.0001). Statistically significant improvements were observed with upadacitinib vs placebo for all multiplicity-controlled secondary endpoints (p<0.0001). Adverse events were reported for 41% of upadacitinib-treated and 37% of placebo-treated patients through week 14. No events of malignancy, major adverse cardiovascular events, venous thromboembolism or deaths were reported with upadacitinib. CONCLUSION: Upadacitinib 15 mg was significantly more effective than placebo over 14 weeks of treatment in bDMARD-IR patients with active AS. No new safety risks were identified with upadacitinib. TRIAL REGISTRATION NUMBER: NCT04169373.

Comparative Efficacy and Safety of Janus Kinase Inhibitors and Secukinumab in Patients with Active Ankylosing Spondylitis: A Systematic Review and Meta-Analysis.

BACKGROUND: Janus kinase (JAK) inhibitors and secukinumab have been demonstrated to be effective treatments for ankylosing spondylitis (AS). However, there have been no head-to-head trials comparing the effectiveness and safety characteristics of JAK inhibitors with secukinumab. This study aimed to evaluate the relative effectiveness and safety of JAK inhibitors and secukinumab in patients with active AS. SUMMARY: A Bayesian network meta-analysis was conducted using direct and indirect data from randomized controlled trials (RCTs) that examined the efficacy and safety of tofacitinib 5 mg, upadacitinib 15 mg, filgotinib 200 mg, and secukinumab 150 mg in patients with active AS who had a poor response or intolerance to nonsteroidal anti-inflammatory drugs (NSAIDs) and were tumor necrosis factor (TNF) inhibitor-naïve. Data from six RCTs comprising 937 patients were analyzed. The Assessment of SpondyloArthritis International Society 20 (ASAS20) response rates were significantly higher in the JAK inhibitors and secukinumab groups than in the placebo group. The surface under the cumulative ranking curve (SUCRA)-based ranking probability based on the ASAS20 response rate suggested that tofacitinib 5 mg had the highest likelihood of being the best treatment for achieving the ASAS20 response rate, followed by filgotinib 200 mg, upadacitinib 15 mg, secukinumab 150 mg, and placebo. The SUCRA-based ranking probability based on the ASAS20 response rate suggested that tofacitinib 5 mg had the highest likelihood of being the best treatment for achieving the ASAS40 response rate, followed by upadacitinib 15 mg, secukinumab 150 mg, filgotinib 200 mg, and placebo. KEY MESSAGES: Tofacitinib 5 mg was the most effective treatment for AS, whereas JAK inhibitors and secukinumab 150 mg were effective treatments in patients with active AS who had a poor response or intolerance to NSAIDs and were TNF inhibitor-naïve.

Indole-3-Acetic Acid Alters Intestinal Microbiota and Alleviates Ankylosing Spondylitis in Mice.

Ankylosing spondylitis (AS) is a systemic, chronic, and inflammatory autoimmune disease associated with the disorder of intestinal microbiota. Unfortunately, effective therapies for AS are lacking. Recent evidence has indicated that indole-3-acetic acid (IAA), an important microbial tryptophan metabolite, can modulate intestinal homeostasis and suppress inflammatory responses. However, reports have not examined the in vivo protective effects of IAA against AS. In this study, we investigated the protective effects and underlying mechanisms through which IAA acts against AS. We constructed a proteoglycan (PG)-induced AS mouse model and administered IAA (50 mg/kg body weight) by intraperitoneal injection daily for 4 weeks. The effects of IAA on AS mice were evaluated by examining disease severity, intestinal barrier function, aryl hydrocarbon receptor (AhR) pathway, T-helper 17 (Th17)/T regulatory (Treg) balance, and inflammatory cytokine levels. The intestinal microbiota compositions were profiled through whole-genome sequencing. We observed that IAA decreased the incidence and severity of AS in mice, inhibited the production of pro-inflammatory cytokines (tumor necrosis factor α [TNF-α], interleukin [IL]-6, IL-17A, and IL-23), promoted the production of the anti-inflammatory cytokine IL-10, and reduced the ratios of pro-/anti- inflammatory cytokines. IAA ameliorated pathological changes in the ileum and improved intestinal mucosal barrier function. IAA also activated the AhR pathway, upregulated the transcription factor forehead box protein P3 (FoxP3) and increased Treg cells, and downregulated the transcription factors retinoic acid receptor-related orphan receptor gamma t (RORγt) and signal transducer and activator of transcription 3 (STAT3) and decreased Th17 cells. Furthermore, IAA altered the composition of the intestinal microbiota composition by increasing Bacteroides and decreasing Proteobacteria and Firmicutes, in addition to increasing the abundances of Bifidobacterium pseudolongum and Mucispirillum schaedleri. In conclusion, IAA exerted several protective effects against PG-induced AS in mice, which was mediated by the restoration of balance among the intestinal microbial community, activating the AhR pathway, and inhibiting inflammation. IAA might represent a novel therapeutic approach for AS.

TNF-α-mediated m6A modification of ELMO1 triggers directional migration of mesenchymal stem cell in ankylosing spondylitis.

Ankylosing spondylitis (AS) is a type of rheumatic disease characterized by chronic inflammation and pathological osteogenesis in the entheses. Previously, we demonstrated that enhanced osteogenic differentiation of MSC from AS patients (AS-MSC) resulted in pathological osteogenesis, and that during the enhanced osteogenic differentiation course, AS-MSC induced TNF-α-mediated local inflammation. However, whether TNF-α in turn affects AS-MSC remains unknown. Herein, we further demonstrate that a high-concentration TNF-α treatment triggers enhanced directional migration of AS-MSC in vitro and in vivo, which enforces AS pathogenesis. Mechanistically, TNF-α leads to increased expression of ELMO1 in AS-MSC, which is mediated by a METTL14 dependent m6A modification in ELMO1 3'UTR. Higher ELMO1 expression of AS-MSC is found in vivo in AS patients, and inhibiting ELMO1 in SKG mice produces therapeutic effects in this spondyloarthritis model. This study may provide insight into not only the pathogenesis but also clinical therapy for AS.

Inflammation Intensity-Dependent Expression of Osteoinductive Wnt Proteins Is Critical for Ectopic New Bone Formation in Ankylosing Spondylitis.

OBJECTIVE: To investigate the molecular mechanism underlying inflammation-related ectopic new bone formation in ankylosing spondylitis (AS). METHODS: Spinal tissues and sera were collected from patients with AS and healthy volunteers and examined for the expression of Wnt proteins. An in vitro cell culture system mimicking the local inflammatory microenvironment of bone-forming sites was established to study the relationship between inflammation and Wnt expression, the regulatory mechanism of inflammation-induced Wnt expression, and the role of Wnt signaling in new bone formation. Modified collagen-induced arthritis (CIA) and proteoglycan-induced spondylitis (PGIS) animal models were used to confirm the key findings in vivo. RESULTS: The levels of osteoinductive Wnt proteins were increased in sera and spinal ligament tissues from patients with AS. Constitutive low-intensity tumor necrosis factor (TNF) stimulation, but not short-term or high-intensity TNF stimulation, induced persistent expression of osteoinductive Wnt proteins and subsequent bone formation through NF-κB (p65) and JNK/activator protein 1 (c-Jun) signaling pathways. Furthermore, inhibition of either the Wnt/ß-catenin or Wnt/protein kinase Cδ (PKCδ) pathway significantly suppressed new bone formation. The increased expression of Wnt proteins was confirmed in both the modified CIA and PGIS models. A kyphotic and ankylosing phenotype of the spine was seen during long-term observation in the modified CIA model. Inhibition of either the Wnt/ß-catenin or Wnt/PKCδ signaling pathway significantly reduced the incidence and severity of this phenotype. CONCLUSION: Inflammation intensity-dependent expression of osteoinductive Wnt proteins is a key link between inflammation and ectopic new bone formation in AS. Activation of both the canonical Wnt/ß-catenin and noncanonical Wnt/PKCδ pathways is required for inflammation-induced new bone formation.

An induction or flare of arthritis and/or sacroiliitis by vedolizumab in inflammatory bowel disease: a case series.

BACKGROUND: In inflammatory bowel disease (IBD), a new biological therapy has recently been approved. Vedolizumab is a humanised IgG1 monoclonal antibody to α4ß7 integrin that modulates gut lymphocyte trafficking. Although an exclusively local effect of vedolizumab could be expected based on the restricted presence of the α4ß7-mucosal vascular addressin cell adhesion molecule 1 complex in the gut, past combined success with anti-tumour necrosis factor, and previous demonstration of α4ß7 integrin in the joint, led to the expectation of a therapeutic efficacy in spondyloarthritis. Nonetheless, the effect of vedolizumab on extraintestinal manifestations-and especially the joint-has not been reported so far. CASE REPORT: A series of five patients with IBD who were treated with vedolizumab and promptly developed new onset or exacerbation of sacroiliitis or arthritis are reported. CONCLUSIONS: Vedolizumab therapy does not seem to show any efficacy in and might even induce arthritis and/or sacroiliitis. However, larger cohort studies are needed to provide information on the prevalence, the evolution and underlying mechanism.

Inhibition of Complement Retards Ankylosing Spondylitis Progression.

Ankylosing spondylitis (AS) is a chronic axial spondyloarthritis (SpA) resulting in back pain and progressive spinal ankyloses. Currently, there are no effective therapeutics targeting AS largely due to elusive pathogenesis mechanisms, even as potential candidates such as HLA-B27 autoantigen have been identified. Herein, we employed a proteoglycan (PG)-induced AS mouse model together with clinical specimens, and found that the complement system was substantially activated in the spinal bone marrow, accompanied by a remarkable proportion alteration of neutrophils and macrophage in bone marrow and spleen, and by the significant increase of TGF-ß1 in serum. The combined treatment with a bacteria-derived complement inhibitor Efb-C (C-terminal of extracellular fibrinogen-binding protein of Staphylococcus aureus) remarkably retarded the progression of mouse AS by reducing osteoblast differentiation. Furthermore, we demonstrated that two important modulators involved in AS disease, TGF-ß1 and RANKL, were elevated upon in vitro complement attack in osteoblast and/or osteoclast cells. These findings further unravel that complement activation is closely related with the pathogenesis of AS, and suggest that complement inhibition may hold great potential for AS therapy.

[Mononeuritis multiplex under the TNF-alpha inhibitor infliximab]. / Mononeuritis multiplex unter dem TNF-alpha-Hemmer Infliximab.

A 21-year-old patient with ankylosing spondylitis under treatment with the TNF-alpha inhibitor infliximab developed a multifocal, demyelinating axonal neuropathy affecting several peripheral nerves simultaneously (mononeuritis multiplex). This represents an additional rare peripheral nervous system side effect of infliximab therapy. The underlying cause is unknown. Intravenous immunoglobulin therapy (0.4 g/kg per day for five days) led to a complete regression of muscle paresis and sensory defects in this case.

Variations in susceptibility to proteoglycan-induced arthritis and spondylitis among C3H substrains of mice: evidence of genetically acquired resistance to autoimmune disease.

OBJECTIVE: To identify and screen the level of arthritis susceptibility in C3H murine strains known to be resistant to proteoglycan (aggrecan)-induced arthritis, and to measure and correlate various immunologic and inflammatory parameters with susceptibility to either arthritis or spondylitis in various C3H substrains. METHODS: Mice of 10 C3H substrains (subcolonies) were immunized with cartilage proteoglycan (aggrecan) for induction of arthritis. Animals were assessed for clinical symptoms, and the peripheral joints and spine were studied by histologic methods. Proteoglycan-specific T cell responses (T cell proliferation and production of interleukin-2 [IL-2], interferon-y, and IL-4) and the B cell response to lipopolysaccharide (LPS) were measured in spleen cell cultures. Serum levels of heteroantibodies and autoantibodies as well as various cytokines (IL-6, IL-10, IL-12, and tumor necrosis factor alpha) and soluble CD44 were determined by enzyme-linked immunosorbent assay. RESULTS: Immunization with cartilage proteoglycan induced severe arthritis in the C3H/HeJCr substrain (95-100% incidence), whereas the original parent mice of the C3H/HeJ colony were resistant to proteoglycan (aggrecan)-induced arthritis. Furthermore, the progressive polyarthritis that is characteristic in susceptible C3H/HeJCr mice was accompanied by progressive inflammation around the spine. In subsequent experiments, 10 different C3H colonies with largely identical genetic backgrounds (all originating from the National Institutes of Health or Jackson Laboratory) exhibited extreme differences in susceptibility. Although none of the laboratory findings, including LPS hyporesponsiveness, immunologic parameters, and inflammatory markers, showed a correlation with susceptibility or resistance in the C3H/HeJCr and C3H/HeJ substrains, respectively, significant differences were found when all arthritic C3H mice were compared with all nonarthritic animals, regardless of their substrain origin. CONCLUSION: Because many of the C3H substrains lost arthritis susceptibility or acquired resistance, our results suggest that a preferred site for a mutation(s) in a gene(s) in a relatively upstream position of the inflammatory cascade is present. This is the first autoimmune model that exhibits extreme differences in arthritis susceptibility in the same murine strain, and is therefore a valuable tool for identification of arthritis-susceptible (or arthritis-suppressive) genes.

Warfarin-induced spondyloarthropathy with pseudotumor-like appearance. A case report.

STUDY DESIGN: This case report illustrates an unusual complication of chronic warfarin administration. OBJECTIVES: The presurgical determination that the destructive process at L1-L2 was not infection or neoplasm involved the recognition that there was instability at this level resulting from chronic stress fractures. SUMMARY OF BACKGROUND DATA: Periosteal or osseous hemorrhagic masses (pseudotumors) have been well described in patients with hemophilia. To the authors' knowledge, this is the first reported case of this well-known phenomenon occurring in the axial skeleton as a consequence of warfarin administration. METHODS: Serial radiographic studies of the lumbar spine were available showing a progressive destructive lesion at L1-L2 and coinciding with the initiation of warfarin anticoagulation after aortic valve replacement. RESULTS: The destructive mass was demonstrated surgically to represent a large partially solidified chronic hematoma. CONCLUSIONS: Patients with stress fractures of the posterior arch and subsequent instability may be subject to development of such a spondyloarthropathy. Recognition of this unusual potential complication of warfarin therapy would prevent an incorrect diagnosis of tumor or infection. Early recognition of its occurrence could lead to early spinal stabilization.