Tocilizumab is a recombinant humanised anti-human monoclonal antibody directed against soluble and membrane‐bound interleukin‐6 receptors (IL‐6R) of the immunoglobulin IgG1 subclass (1):
- IL‐6, a pleiotropic cytokine produced by cells of various types, has diverse biological functions
- is involved in T‐cell activation, stimulation of hematopoiesis, and in particular, induction of acute phase proteins; these acute phase proteins (e.g. ESR, CRP) are markedly high in individuals with GCA and are monitored clinically for disease activity
- IL‐6 is locally produced in granulomatous lesions in the vasculitic arteries, as well as by circulating monocytes in GCA patients
- people with giant cell arteritis who have an injection of tocilizumab every week or two weeks have an improved chance of being symptom‐free after a year
- the systematic review states that "people treated with tocilizumab every four weeks probably have an improved chance of being symptom‐free after a year"
Study evidence that tocilizumab was confirmed to have an important steroid-sparing effect and a good safety profile in GCA patients (2).
Reference:
- Antonio AA, Santos RN, Abariga SA. Tocilizumab for giant cell arteritis. Cochrane Database Syst Rev. 2022 May 13;5(5):CD013484.
- Regola F, Cerudelli E, Bosio G, Andreoli L, Tincani A, Franceschini F, Toniati P. Long-term treatment with tocilizumab in giant cell arteritis: efficacy and safety in a monocentric cohort of patients. Rheumatol Adv Pract. 2020 May 15;4(2):rkaa017.