A scoping review of the use of non-biologic disease modifying anti-rheumatic drugs in the management of large vessel vasculitis

- There is lack of high quality evidence to guide use of conventional DMARDs in TA.
- Methotrexate, leflunomide, azathioprine, cyclophosphamide and mycophenolate are useful in TA.
- Randomized trials suggest inefficacy of methotrexate, HCQS and cyclosporine in GCA.
- Leflunomide, azathioprine, mycophenolate, cyclophosphamide and dapsone are effective in GCA.
- Multicentric randomized placebo-controlled trials are urgently needed in TA and GCA.

Takayasu's arteritis (TA) and Giant cell arteritis (GCA) comprise the large vessel vasculitides (LVV). Patients with LVV are treated with disease-modifying anti-rheumatic drugs (DMARDs), both conventional (cDMARDs) and biologic (bDMARDs). We undertook a scoping review to assess the effectiveness of cDMARDs in TA and GCA. We could identify 11 studies in TA and 18 studies in GCA. There were only 3 randomized controlled trials on methotrexate, one on hydroxychloroquine and two on cyclosporine in GCA, the others being case series (including all studies on TA). Most of these studies had small patient numbers (median 15 in TA and 27 in GCA). Outcome measures reported in different studies were heterogenous. Overall, methotrexate, leflunomide, azathioprine, mycophenolate mofetil and cyclophosphamide were effective in TA (low quality of evidence). Methotrexate (high quality of evidence), hydroxychloroquine and cyclosporine (moderate quality of evidence) appeared to be ineffective in GCA. Azathioprine (moderate quality of evidence), leflunomide, mycophenolate mofetil, cyclophosphamide and dapsone (low quality of evidence) were effective in GCA. There exists a paucity of high quality evidence to guide use of cDMARDs in TA and GCA. There is an unmet need to conduct large multi-centric randomized placebo-controlled trials to accurately assess the utility on cDMARDs in LVV.