Study: Ixekizumab Improves Symptoms of Non-Radiographic Axial Spondyloarthritis

The COAST-X study evaluated ixekizumab (Taltz, Eli Lilly) in patients with non-radiographic axial spondyloarthritis.

Ixekizumab (Taltz, Eli Lilly) improved the signs and symptoms of non-radiographic axial spondyloarthritis (nr-axSpA), according to new data from the phase 3 COAST-X study.

The findings were presented at the American College of Rheumatology/Association of Rheumatology Professionals Annual Meeting in Atlanta, Georgia.

AxSpA, a chronic inflammatory disease involving the sacroiliac joints and spine skeleton, is estimated to affect approximately 4.5 million adults worldwide. Patient subsets include those with and without clearly detectable radiographically-defined structural damage. Nonradiographic disease is part of the same spectrum of disease but may occur as early disease or may be a separate entity that never progresses to radiographic disease. Although both subsets share a similar burden of disease, biologic treatment options for patients with nr-AxSpA are more limited.

Ixekizumab is currently approved for the treatment of moderate-to-severe plaque psoriasis, active psoriatic arthritis, and active ankylosing spondylitis.

The 52-week COAST-X study evaluated the efficacy and safety of ixekizumab for the treatment of nr-axSpA in patients who are biologic disease-modifying anti-rheumatic drug (bDMARD)-naïve. Eligible patients have an established diagnosis of nr-axSpA and active disease.

A total of 303 adult patients with active nr-axSpA were randomized to receive either ixekizumab 80 mg subcutaneously every 4 weeks or 2 weeks (following 80 mg or 160 mg starting dose at week 0) or placebo.

According to the data, the study showed:

  • At week sixteen, 35% of patients treated with ixekizumab every 4 weeks and 40% of patients treated with ixekizumab every 2 weeks achieved Assessment of Spondyloarthritis International Society 40 (ASAS40) response compared with 19% of patients treated with placebo.
  • At week fifty-two, 30% of patients treated with ixekizumab every 4 weeks and 31% of patients treated with ixekizumab every 2 weeks achieved ASAS40 response compared with 13% of patients treated with placebo.

Major secondary endpoints in the study were also met at weeks 16 and 52, including significant improvement in Ankylosing Spondylitis Disease Activity Score (ASDAS), significant improvement in Bath Ankylosing Spondylitis Disease Activity (BASDAI), proportion of patients achieving low disease activity (ASDAS <2.1), significant improvement in sacroiliac joint inflammation as assessed by MRI, and significant improvement in 36-Item Short Form Health Survey Physical Component Summary Score.

“In the COAST-X study, Taltz improved the signs and symptoms of non-radiographic axSpA as measured by ASAS40, as well as reduced inflammation on MRI, an important objective measure of disease activity,” study investigator Atul Deodhar MD, professor of medicine at Oregon Health & Science University, said in a statement. “If approved for this patient population Taltz could be an important treatment option to help address chronic, debilitating symptoms for people living with non-radiographic axSpA.”

In a previous Specialty Pharmacy Times® Insights video series, Deodhar provided clinical expertise in using various pharmacologic therapies in the treatment of axSpA. In the video, Deodhar discussed the importance of interleukin 17A (IL-17A) in the pathology of AxSpA, in which IL-17A is high in the serum of patients with the disease. Ixekizumab works by binding with IL-17A cytokine and inhibiting its interaction with the IL-17A receptor.

“We are now entering an era where we will have more and more potent options to control the signs and symptoms and hopefully also prevent further radiographic damage in patients with axial spondyloarthritis,” Deodhar said in the video. “My own experience tells me that now, with the current armamentarium that we have, we can definitely give much better quality of life to these patients and prevent disability if we catch them early and if we treat them aggressively.”

According to Rhonda Pacheco, PharmD, global brand development leader for immunology at Lilly, ixekizumab would be the first IL-17A antagonist approved nr-axSpA if accepted by regulatory authorities.

No new or unexpected safety signals were identified with ixekizumab in the study.

Based on these results, Lilly has submitted for US regulatory approval for adults with active nr-axSpA, according to the press release.

Reference

ACR 2019: Lilly Presents Positive New Data from COAST-X a Phase 3 Study of Taltz (ixekizumab) in Patients with Non-Radiographic Axial Spondyloarthritis [news release]. Eli Lilly’s website. https://investor.lilly.com/news-releases/news-release-details/acr-2019-lilly-presents-positive-new-data-coast-x-phase-3-study. Accessed November 12, 2019.