Tocilizumab in its subcutaneous form is the first-ever drug designated for giant cell arteritis which affects 230,000 people in the U.S
The Food and Drug Administration has approved the first drug for giant cell arteritis, a condition associated with polymyalgia rheumatica affecting 230,000 people in the U.S.
Approved in its subcutaneous form, tocilizumab (Actemra, Roche and Genentech) is now used to treat moderate to severe active rheumatoid arthritis. The FDA granted breakthrough therapy designation for tocilizumab for giant cell arteritis in October and in May, the FDA formally expanded the drug’s approved indications to include giant cell arteritis.
Giant cell arteritis (GCA) is a chronic vasculitis primarily affecting Caucasian women over 50 years old. It is most common in patients with polymyalgia rheumatic affecting blood vessels of the head, specifically temporal arteries, but large arteries, such as the aorta, can be affected as well. Up until now, GCA was primarily treated with high dose corticosteroids to be tapered over time. If left untreated, patients risk blindness.
The FDA’s decision is based on the results of GiACTA, a double-blind, placebo-controlled clinical trial of 251 patients with giant cell arteritis who were treated with subcutaneous tocilizumab.
56 percent of 251 patients in the weekly tocilizumab group and 53.1 percent in the every other week tocilizumab group achieved sustained remission at 12 months as compared to only 14 percent in the short-course prednisone group (p < 0.0001).
Tocilizumab plus a 26-week prednisone taper was superior to both short- and long-course prednisone tapers for the achievement of sustained remission at 52 weeks.
The addition of tocilizumab to prednisone also led to a substantial reduction in the cumulative prednisone doses required to control GCA.
In the key secondary efficacy comparison, the percentage of patients in sustained remission in each tocilizumab group was also superior to that of patients in the long-course prednisone group (17.6%) (p ≤ 0.0002). The median cumulative steroid exposure in both tocilizumab groups was less than half that of those in the long-course prednisone group.
In GCA, tocilizumab’s safety profile was consistent with its known safety profile for other approved conditions. It carries a boxed warning for the risk of serious infections.
Intravenous tocilizumab was previously approved for moderate to severe active rheumatoid arthritis, systemic juvenile idiopathic arthritis and polyarticular juvenile idiopathic arthritis.
More from Rheumatology Network on giant cell arteritis:
FDA News Release: "FDA approves first drug to specifically treat giant cell arteritis," May 22, 2017.