FDA Approves Ixekizumab for Treating Active Ankylosing Spondylitis

In late August, U.S. Food and Drug Administration (FDA) approved the use of ixekizumab (Taltz) in an 80 mg/mL dose injection for treating adults with active radiographic axial spondyloarthritis, also known as ankylosing spondylitis (AS).¹

This is the third FDA approval for ixekizumab. In March 2016, the FDA first approved the treatment for adults with moderate to severe plaque psoriasis who are candidates for systemic therapy or phototherapy. In December 2017, the FDA approved ixekizumab for treating adults with active psoriatic arthritis.

The Supporting Research
This new approval was based on the results of two randomized, double-blind, placebo-controlled, phase 3 studies. These studies evaluated the safety and efficacy of ixekizumab in patients (N=657) with active AS. Patients received an 80 mg/mL subcutaneous injection of ixekizumab once every four weeks.

The first study, called COAST-V, enrolled patients who were biologic disease-modifying anti-rheumatic drug (bDMARD) naive. The second study, called COAST-W, enrolled patients who had previously had an inadequate response to anti-tumor necrosis factor (TNF) agents or were intolerant to anti-TNF agents. The primary efficacy endpoint of the studies was the proportion of patients who achieved an Assessment of Spondyloarthritis International Society 40 (ASAS40) response compared with the proportion of placebo-treated patients who achieved ASAS40 at Week 16.

At Week 16 of the COAST-V study, the ASAS40 responses for ixekizumab-treated and placebo-treated patients were 48% and 18%, respectively. This result for patients treated with ixekizumab was considered to be a clinically meaningful, statistically significant (P<0.0001) improvement. At Week 16 of the COAST-W study, the ASAS40 responses for ixekizumab-treated and placebo-treated patients were 25% and 13%, respectively. Again, the result for patients treated with ixekizumab demonstrated clinically meaningful improvement and was statistically significant (P<0.05).

In both studies, key secondary endpoints were met in ixekizumab-treated patients. The ASAS20 response in the COAST-V study at Week 16 was 64% in ixekizumab-treated patients and 40% in placebo-treated patients (P=0.0015). In the COAST-W study at Week 16, the ASAS20 was 48% ixekizumab-treated patients and 30% in placebo-treated patients (P<0.01).

No new safety risks were identified.

Michele B. Kaufman, PharmD, BCGP, is a freelance medical writer based in New York City and a pharmacist at New York Presbyterian Lower Manhattan Hospital.

Reference

1. Eli Lilly and Co. News release: Lilly receives U.S. FDA approval for Taltz (ixekizumab) for the treatment of active ankylosing spondylitis (radiographic axial spondyloarthritis). 2019 Aug 26.