To evaluate the efficacy and safety of ustekinumab (UST) in giant cell arteritis (GCA).
We conducted a prospective, open-label trial of UST in patients with active new-onset or relapsing GCA. Active disease was defined as the presence of GCA symptoms and elevation of erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) level within 6 weeks of baseline. All patients received a 24-week prednisone taper and subcutaneous UST 90 mg at baseline and at weeks 4, 12, 20, 28, 36, and 44. The primary endpoint, prednisone-free remission, was defined as the absence of relapse through week 52 and normalization of the ESR and CRP level. Relapse was defined as the recurrence of GCA symptoms requiring treatment intensification. A sensitivity analysis excluding ESR/CRP level normalization from the prednisone-free remission definition was performed.
The study enrolled 13 patients (target sample size 20). Enrollment was closed prematurely after 7 of the initial 10 patients relapsed. Five patients (39%) had new-onset disease. The initial prednisone doses were 20 mg (1 patient), 40 mg (9 patients), and 60 mg (3 patients). All patients entered disease remission within 4 weeks of baseline. Only 3 (23%) achieved the primary endpoint. Of the 10 patients (77%) who failed to achieve the primary endpoint, 7 relapsed after a mean period of 23 weeks. The remaining 3 patients met the alternative definition of prednisone-free remission that did not require ESR/CRP level normalization. One serious adverse event occurred.
UST combined with 24 weeks of prednisone was associated with a high rate of treatment failure in this prospective GCA trial.