Ixekizumab Associated with Significant Improvements in PsA

Ixekizumab significantly helped signs and symptoms of psoriatic arthritis in a phase 3 study reported at the annual meeting of the European League Against Rheumatism Annual Congress (EULAR 2016) in London on June 10.

The study, led by Philip J. Mease of Swedish Medical Center and the University of Washington, Seattle, found improvements at 52 weeks compared with baseline in the American College of Rheumatology 20/50/70, Health Assessment Questionnaire-Disability Index, Disease Activity Score 28 diarthroidal joint count based on C-reactive protein, Psoriasis Area and Severity Index 75, 90, 100, Leeds Enthesitis Index, and Leeds Dactylitis Index-Basic. The research builds on Spirit-P1, a phase 3 double-blind treatment study that found that ixekizumab was superior to placebo in response at week 24 in psoriatic arthritis patients who had not previously used biologic disease-modifying anti-rheumatic drugs.

Building on Spirit-P1’s double-blind treatment period (0 to 24 weeks), researchers wanted to evaluate efficacy and safety of ixekizumab over 52 weeks. A total of 381 patients were assigned to receive 80 mg of ixekizumab every 2 or 4 weeks. Researchers used the variety of aforementioned disease assessment tools to measure efficacy. Ultimately, 304 patients completed the extension period.  [[{"type":"media","view_mode":"media_crop","fid":"49290","attributes":{"alt":"©LipowskiMilan/Shutterstock.com","class":"media-image media-image-right","id":"media_crop_6466153303005","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"5930","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"font-size: 13.008px; line-height: 1.538em; float: right;","title":"©LipowskiMilan/Shutterstock.com","typeof":"foaf:Image"}}]]

Additionally, treatment-emergent adverse events in the study’s extension period (weeks 24 to 52) were similar to that seen in the double-blind treatment period. The majority of those adverse events were mild or moderate in severity, the authors wrote. Although serious adverse events occurred in 12 patients, there were no deaths in the extended period population. “The safety profile of ixekizumab observed in the extended period was similar to that observed in the double-blind treatment period and other phase 3 studies of ixekizumab in patients with plaque psoriasis,” the authors wrote.

Ixekizumab, which binds to the IL-17A protein causing inflammation, was approved earlier this year by the U.S. Food and Drug Administration for use in patients with moderate to severe psoriatic arthritis. The three anti-IL17 medications approved or under development to treat psoriatic arthritis-- secukinumab, ixekizumab, and brodalumab-all appear effective and as safe as other biologic medications that are approved by the Food and Drug Administration, according to a February 2016 review in the American Journal of Clinical Dermatology.

Disclosures:

The study’s lead author, Dr. Mease, reports grant and research support from a variety of pharmaceutical companies, including Eli Lilly and Company (the manufacturer of ixekizumab).

References:

Mease PJ, Okada M, Kishimoto M, et al. Efficacy and safety of ixekizumab in patients with active psoriatic arthritis: 52 week results from a phase 3 study (Spirit-P1). EULAR 2016.

Mease PJ, van der Heijde D, Ritchlin CT, et al. “A Randomized, Double-Blind, Active- and Placebo-Controlled Phase 3 Study of Efficacy and Safety of Ixekizumab, Adalimumab, and Placebo Therapy in Patients Naïve to Biologic Disease Modifying Anti-Rheumatic Drugs with Active Psoriatic Arthritis.” ACR/ARHP 2015. Abstract 977.

Canavan TN, Elmets CA, Cantrell WL, Evans JM, Elewski BE. “Anti-IL-17 Medications Used in the Treatment of Plaque Psoriasis and Psoriatic Arthritis: A Comprehensive Review.” Am J Clin Dermatol. 2016 Feb;17(1):33-47. doi: 10.1007/s40257-015-0162-4.