By David Borenstein MD, Executive Editor, theSpineCommunity.com
The Food and Drug Administration approved the Il-17A inhibitor, Cosentyx® (secukinumab), for the treatment of ankylosing spondylitis (AS). AS, an autoimmune disease that affects the spine and large joints, causes inflammation that can lead to severe, chronic pain, and in worst cases can lead to new bone formations resulting in spinal fusion. The availability of Cosentyx allows another option for patients with AS who have failed anti-TNF therapy.
Until the approval of Cosentyx, the only biologic therapy available for the treatment of AS was anti-tumor necrosis factor antibodies directed against the protein directly or its receptor. Although this group of agents was effective in controlling the signs and symptoms of the illness, a significant proportion of AS patients, a third or more, were unresponsive to this category of biologic therapy.
Interleukin-17A (IL-17) is a protein produced by immune cells in the setting of ankylosing spondylitis (AS). It seems that this cytokine (a messenger between cells) plays an important role in the symptoms associated with AS. The characteristic inflammatory symptoms associated with AS include prolonged morning stiffness lasting for hours, improvement with activity, overall fatigue, and weight loss.
Cosentyx is an anti-IL17 antibody that decreases levels of this cytokine in AS patients. A New England Journal of Medicine article reported the benefit of Cosentyx in AS patients. A total of 371 individuals participated in the 16 week study. At week 16, 61%, 60%, and 29% had 20% improvement or more in improved pain and function with subcutaneous doses of 150 mg, 75 mg, or placebo, respectively. The study was continued with monthly injections for a total of a year. The benefits from secukinumab were measured throughout the yearlong study most consistently in the 150 mg subcutaneous injection.
As with all biologic agents, increased potential for infections is reported in patients exposed to IL-17 therapy, similar to that recognized with anti-tumor necrosis antibody therapy. The number of infections did not reach a number to be considered a serious adverse event.
Reference: Baeten D, Sieper J, BraUN j ET AL. Secukinumab, an interleukin-17A inhibitor, in ankylosing spondylitis. N Engl J Med 2015;373:2534-2548