Adults with giant cell arteritis – a form of vasculitis, or inflammation of blood vessels – received good news this week with the US FDA expanding the approved use of subcutaneous Actemra (tocilizumab) to treat adults suffering from the condition. This new indication provides the first FDA-approved therapy, specific to this type of vasculitis.
“We expedited the development and review of this application because this drug fulfills a critical need for patients with this serious disease who had limited treatment options,” said Badrul Chowdhury, M.D., Ph.D., director of the Division of Pulmonary, Allergy, and Rheumatology Products in the FDA’s Center for Drug Evaluation and Research.
Giant cell arteritis is a form of vasculitis that results in inflammation of blood vessels. This inflammation causes the arteries to narrow or become irregular, impeding adequate blood flow. In giant cell arteritis, the vessels most involved are those of the head, especially the temporal arteries (located on each side of the head). The standard treatment of the disorder is typically high doses of corticosteroids that are tapered over time.
The approval of Actemra for giant cell arteritis was based on the results of a double-blind, placebo-controlled study with 251 patients with giant cell arteritis. The primary efficacy endpoint was the proportion of patients achieving sustained remission from Week 12 through Week 52. Sustained remission was defined as the absence of symptoms of giant cell arteritis, normalization of inflammatory laboratory tests, and tapering the use of prednisone (a steroid drug). A greater proportion of patients receiving subcutaneous Actemra with standardized prednisone regimens achieved sustained remission from Week 12 through Week 52 as compared to patients receiving placebo with standardized prednisone regimens. The cumulative prednisone dose was lower in treated patients with Actemra relative to placebo.
Subcutaneous Actemra is also used for the treatment of moderate to severely active rheumatoid arthritis. Intravenous Actemra was also previously approved for the treatment of moderate to severely active rheumatoid arthritis, systemic juvenile idiopathic arthritis and polyarticular juvenile idiopathic arthritis. Intravenous administration is not approved for giant cell arteritis.