Tocilizumab in giant cell arteritis: Multicenter open-label study of 22 patients

Objective: To assess the efficacy of tocilizumab (TCZ) in giant cell arteritis (GCA) patients with refractory disease and/or with unacceptable side effects due to corticosteroids.

Methods: A retrospective multicenter open-label study on 22 GCA patients treated with TCZ at standard dose of 8mg/kg/month. The main outcomes were achievement of disease remission and reduction of corticosteroid dose.

Results: The mean age ± standard deviation of patients was 69 ± 8 years. The main clinical features at TCZ onset were polymyalgia rheumatica (n = 16), asthenia (n = 7), headache (n =5), constitutional symptoms (n = 4), jaw claudication (n = 2), and visual loss (n = 2). Besides corticosteroids and before TCZ onset, 19 of 22 patients had also received several conventional immunosuppressive and/or biologic drugs. Of 22 patients, 19 achieved rapid and maintained clinical improvement following TCZ therapy. Also, after a median follow-up of 9 (interquartile range: 6-19) months, the C-reactive protein level had fallen from 1.9 (1.2-5.4) to 0.2 (0.1-0.9)mg/dL (p < 0.0001) and the erythrocyte sedimentation rate decreased from 44 (20-81) to 12 (2-20)mm/1st hour (p = 0.001). The median dose of prednisone was also tapered from 18.75 (10-45) to 5 (2.5-10)mg/day (p < 0.0001). However, TCZ had to be discontinued in 3 patients due to severe neutropenia, recurrent pneumonia, and cytomegalovirus infection. Moreover, 1 patient died after the second infusion of TCZ due to a stroke in the setting of an infectious endocarditis.

Conclusion: TCZ therapy leads to rapid and maintained improvement in patients with refractory GCA and/or with unacceptable side effects related to corticosteroids. However, the risk of infection should be kept in mind when using this drug in patients with GCA.