There is an unmet need for safer and more efficacious treatment of GCA and PMR. Up to 50-60% of patients may experience flares on glucocorticoids (GC) and GC resistant cases are seen especially in the context of large vessel vasculitis.
BSR guidelines advocate initial prednisolone 15-20 mg daily and 2015 ACR/EULAR guidelines for the management of PMR recommend minimum effective GC dose within a range of 12.5–25 mg prednisone equivalent daily as initial treatment. Dose tapering schedules in PMR should be individualized, with regular monitoring of disease activity, laboratory markers and adverse events (Figure 3). Intramuscular methylprednisolone given every 3-4 weeks is an effective alternate treatment strategy in patients where a lower cumulative GC dose is desirable.
For GCA, guidelines recommend an initial dose of prednisone equivalent of 40–60 mg/day and GC dose tapering should be individualized according to the clinical course. Treatment with intravenous methylprednisolone pulse therapy (usually 1 g daily for 3 consecutive days) is recommended for patients with severe ischemic manifestations such as visual disturbance, cerebrovascular accidents or symptomatic, progressive large artery stenosis of the extremities.
A limited number of RCTs support the adjunctive use of MTX as GC sparing agent in PMR on an individualized basis. Early use of methotrexate may be considered in patients with a high risk for relapses and/or GC-induced adverse events. MTX also has benefits in GCA and a meta-analysis of three MTX trials revealed a marginal reduction in risk for the first relapse, higher rates of GC-free remission and lower cumulative GC doses. MTX is included in EULAR and British treatment recommendations as adjunctive therapy.
RCTs of other conventional DMARDs such as azathioprine, cyclosporine A and dapsone, as well as tumor necrosis factor-alpha (TNF-a) blocking agents, have been disappointing, whereas published case series on the successful use of leflunomide and tocilizumab in treatment resistant cases with PMR and GCA are promising. The GiACTA trial is an ongoing multicenter trial investigating the efficacy of tocilizumab in maintaining remission in GCA. RCTs completed or ongoing include safety and efficacy of secukinumab (anti-IL17A) and canakinumab (anti-IL1b) in PMR, anti-IL-1b antibody gevokizumab in GCA, with results expected in the near future.
Disclosure of Interest B. Dasgupta Grant/research support from: Napp, Consultant for: GSK,Roche,Servier,Merck