[ANCA-associated vasculitis after achieving remission]

[Biologics for connective tissue diseases and vasculitides]

Despite therapy with glucocorticoids (GC) and conventional immunosuppressants, patients with connective tissue diseases and vasculitides often develop functionally relevant and prognostically unfavourable internal organ damage. Based on new pathogenetic insights, biologics and small molecules have recently been studied as targeted therapies for collagen vascular diseases and vasculitides. The B lymphocyte stimulator antagonist belimumab has been used for the treatment of systemic lupus erythematosus (SLE) for several years and has recently also been approved as an add-on therapy for lupus nephritis. Anifrolumab, an antibody against the type‑1 interferon receptor, has also been shown to be effective in phase III trials for the treatment of SLE. The interleukin (IL)-6-antagonist tocilizumab showed efficacy in the treatment of interstitial lung disease (ILD) in systemic sclerosis (SSc) and thus has been approved in the USA, although the phase III trial had a negative primary endpoint. In Europe the tyrosine inhibitor nintedanib is approved for progressive ILD in SSc. Tocilizumab is approved for the treatment of giant cell arteritis and reduces both the risk of recurrence and the cumulative GC requirement. The B‑lymphocyte depleting antibody rituximab is approved for induction and maintenance therapy of granulomatosis with polyangiitis and microscopic polyangiitis (MPA) and is currently also being investigated for the treatment of eosinophilic granulomatosis with polyangiitis (EGPA). In patients with EGPA, the IL‑5 antibody mepolizumab leads to improved disease control and reduces GC requirements. A phase III trial of the small molecule antagonist avacopan targeting the complement C5a receptor as a replacement for high-dose GC in induction therapy of GPA and MPA met its primary endpoints. Various other biologics and small molecule antagonists are currently in clinical development for several type of vasculitis and collagen vascular diseases, some of them at advanced stages.

[Glucocorticoids in the treatment of giant cell arteritis : How much, how long and how to spare?]

Treatment of giant cell arteritis (GCA) with high-dose glucocorticoids (GC) regularly leads to a control of the inflammatory activity, so that high-dose GC is still the recommended standard treatment in the current guidelines; however, after discontinuation of GC treatment or reduction of the GC dosage, relapses occur in up to 70% of patients in the further course of the disease, making it necessary to resume treatment or increase the dosage. As a consequence many patients therefore have to be treated with GC often in high doses over several years, which results in a high cumulative exposure to GC. The risk for GC-associated diseases, such as diabetes, glaucoma, osteoporosis or severe infections is therefore significantly increased for patients with giant cell arteritis. For patients with GC-associated comorbidities or increased risk of developing them or patients with a relapse, the current guidelines therefore recommend GC-sparing treatment with tocilizumab or alternatively methotrexate. It is currently unclear over what period of time patients should be treated with GC and GC-sparing treatment, since high-quality study data on de-escalation strategies for GCA are currently still lacking. Decisions on treatment duration and intensity must therefore be made individually for each patient, taking into account general and patient-specific risk factors for a GC-dependent course, GCA-associated vascular damage (stenoses, aneurysms, visual loss) and treatment-associated complications.