Immunomodulatory drugs for maintaining remission in giant cell arteritis

For people with giant call arteritis (GCA), long-term oral corticosteroids are continued until remission of disease activity is achieved (ie the patient’s symptoms resolve, their organ function stabilises and their inflammatory markers normalise). People with giant cell arteritis typically continue oral corticosteroids for 2 years or more, and it is uncommon to stop therapy before 18 months.

The dose may then be tapered very slowly under specialist advice. An example of tapering long-term, high-dose oral corticosteroids can be found in Example of tapering long-term, high-dose oral corticosteroids for systemic vasculitides.

Combination therapy, with oral corticosteroids and another immunomodulatory drug, is recommended for corticosteroid sparing (to minimise the total dose and adverse effects of corticosteroids). Tocilizumab is an interleukin-6 inhibitor (biological disease-modifying antirheumatic drug [bDMARD]) that may be used as a corticosteroid-sparing agent in giant cell arteritis. A 2017 randomised controlled trial¹ demonstrated that combination therapy with oral corticosteroids plus tocilizumab resulted in higher rates of sustained remission, and lower corticosteroid-associated disease than monotherapy with oral corticosteroidsStone, 2017. It is important to note that tocilizumab supresses inflammatory markers, so the markers are not useful for monitoring disease activity in patients taking tocilizumab. The usual dosage of tocilizumab for giant cell arteritis is:

For additional considerations specific to tocilizumab use, see Specific considerations for use of biological or targeted-synthetic disease-modifying antirheumatic drugs (b/tsDMARDs).

Some evidence provides support for the use of methotrexate in giant cell arteritis:

• in combination with systemic corticosteroids initially (during induction therapy)
• as a corticosteroid-sparing drug in patients unable to take tocilizumabHellmich, 2020.

Methotrexate dose is adjusted based on clinical response and adverse effects. The usual initial dosage of methotrexate for giant cell arteritis is:

For additional considerations specific to methotrexate use, see Specific considerations for use of conventional synthetic disease-modifying antirheumatic drugs (csDMARDs).