ABSTRACT
The mainstay of therapy of large vessel vasculitides (LVV) remains glucocorticoids (GC). Although most patients initially achieve disease remission, relapses and GC dependence are seen in more than two-thirds of cases. Conventional synthetic disease-modifying antirheumatic drugs (DMARDs) showed little or no steroid sparing effects, while biological agents represent a valid therapeutic option in patients with severe and/or relapsing LVV.
Subject(s)
Biological Therapy/methods , Giant Cell Arteritis/therapy , Takayasu Arteritis/therapy , Antirheumatic Agents/therapeutic use , Glucocorticoids/therapeutic use , HumansABSTRACT
OBJECTIVE: Different lines of evidence have highlighted the role of IL-17A in the inflammatory process occurring in giant cell arteritis (GCA). The aim of the present study was to assess whether the IL17A locus influences GCA susceptibility and its clinical subphenotypes. METHODS: We carried out a large meta-analysis including a total of 1266 biopsy-proven GCA patients and 3779 healthy controls from four European populations (Spain, Italy, Germany and Norway). Five IL17A polymorphisms (rs4711998, rs8193036, rs3819024, rs2275913 and rs7747909) were selected by tagging and genotyped using TaqMan assays. Allelic combination and dependency tests were also performed. RESULTS: In the pooled analysis, two of the five analysed polymorphisms showed evidence of association with GCA (rs2275913: PMH=1.85E-03, OR=1.17 (1.06-1.29); rs7747909: PMH=8.49E-03, OR=1.15 (1.04-1.27)). A clear trend of association was also found for the rs4711998 variant (PMH=0.059, OR=1.11 (1.00-1.23)). An independent effect of rs2275913 and rs4711998 was evident by conditional regression analysis. In addition, the haplotype harbouring the risk alleles better explained the observed association than the polymorphisms independently (likelihood p value <10(-05)). CONCLUSIONS: Polymorphisms within the IL17A locus show a novel association with GCA. This finding supports the relevant role of the Th17 cells in this vasculitis pathophysiology.
Subject(s)
Giant Cell Arteritis/genetics , Interleukin-17/genetics , Case-Control Studies , Gene Frequency , Genetic Predisposition to Disease , Genotype , Haplotypes , Humans , Polymorphism, GeneticABSTRACT
Glucocorticoids (GC) are the mainstay of treatment of large-vessel vasculitis (LVV), but a sizeable number of patients relapse upon tapering the GC dose or after discontinuation of GC therapy. In addition, GC cause numerous adverse events. Therefore, in patients with longstanding disease and in those at risk for GC-related adverse events, the use of alternative therapeutic agents should be considered. Interleukin-6 (IL-6) is a key player in the pathogenesis of LVV. Preliminary data suggest the efficacy of the IL-6 receptor inhibitor tocilizumab (TCZ) in patients with LVV. We report 2 treatment-naïve patients with a recent diagnosis of LVV who received monthly TCZ infusions (8 mg/kg body weight) for 6 consecutive months as monotherapy because of relative contraindications and patients' reluctance to take GC. In both cases we observed a complete clinical response and normalisation of inflammatory markers as well as a decrease in vascular FDG uptake and SUV ratio on fluorodeoxyglucose positron emission/computerised tomography. Serum IL-6 and soluble IL-6 receptor (sIL-6R) levels rose in both patients after TCZ therapy. TCZ may be an effective alternative to GC treatment for LVV patients at risk for GC-related adverse events. Larger studies are required to confirm our findings.
