Long-term 104-week follow-up of the phase 3 MEASURE 2 study confirmed sustained secukinumab efficacy and safety for signs and symptoms of active ankylosing spondylitis (AS), stated Helena Marzo-Ortega, PhD, Honorary Clinical Assistant Professor, University of Leeds, United Kingdom, in a 2016 European League Against Rheumatism Annual Congress presentation. Interleukin (IL)-17A, a proinflammatory cytokine, has been implicated in the pathogenesis of the disease, she stated.
Analysis of results at week 52 of the randomized, double-blind, placebo-controlled clinical trial had shown improved signs and symptoms with use of secukinumab, an anti–IL-17A monoclonal antibody. MEASURE 2 included 219 patients with active AS classified by modified New York criteria (ie, Bath Ankylosing Spondylitis Disease Activity Index [BASDAI] score ≥4, and a spinal pain score ≥40 on a visual analog scale [0-100 mm]) despite therapy with nonsteriodal anti-inflammatory drugs. Participants had a mean age of 43 years, and disease duration of 6.2 years; 70% were men. At baseline, they were randomized to receive subcutaneous secukinumab 150 mg or 75 mg, or placebo, and were treated subsequently at weeks 1, 2, 3, and every 4 weeks from week 4. At week 16, patients receiving placebo were assigned to receive subcutaneous secukinumab 150 mg or 75 mg every 4 weeks. The primary end point was Assessment of SpondyloArthritis International Society (ASAS)20 at week 16.
Dr Marzo-Ortega noted that, in the MEASURE 2 population, 39% of patients had inadequate responses or intolerance to previous anti–tumor necrosis factor (TNF) therapy. For patients receiving the 150-mg and 75-mg secukinumab doses, 104-week treatment completion rates were 83.3% (60/72) and 78.1% (57/73), respectively. The placebo group completion rate was 77.0% (57/74).
Although improvements at week 16 were not significant in the 75-mg secukinumab group, significant improvements were seen for all end points—except ASAS partial remission—at week 16 in the 150-mg secukinumab group. ASAS20 and ASAS40 response rates at week 104 were 71.5% and 47.5%, respectively, with both secukinumab doses.
For all of the secondary end points (ASAS 5/6/20/40, high-sensitivity C-reactive protein, BASDAI, Short Form-36 Physical Component Summary, and ASAS partial remission), secukinumab improvements were sustained through week 104. Looking separately at week 104 responses in anti-TNF–naïve patients, Dr Marzo-Ortega and colleagues observed ASAS20 and ASAS40 responses of 76.9% and 56.4%, and 80.0% and 60.0%, respectively, for the secukinumab 150-mg and 75-mg groups. In anti-TNF therapy patients receiving 150-mg and 75-mg doses, ASAS20 and ASAS40 responses were 85.0% and 50.0%, and 68.8% and 43.8%, respectively.
Safety was consistent with previous reports of secukinumab treatment, with nasopharyngitis, upper respiratory tract infection, diarrhea, and influenza the most frequently reported adverse events. Exposure-adjusted incidence rates per 100 patient-years with secukinumab treatment were 1.2 for serious infections and infestations, 1.4 for irritable bowel disease, 0.5 for malignant/unspecified tumors, and 0.7 for major adverse clinical events. No tuberculosis, opportunistic infections, or suicide-related adverse events were reported.
One death caused by acute myocardial infarction was reported in the secukinumab 75-mg dose group during the 16-week, placebo-controlled period. However, it was not considered by Dr Marzo-Ortega to be related to study treatment.
“Regardless of anti-TNF status at baseline, secukinumab provided sustained improvement through 2 years in the signs and symptoms of active AS with improved physical function. Secukinumab was well-tolerated through 2 years, with a safety profile consistent with that previously reported in phase 3 clinical trials in psoriasis, psoriatic arthritis, and AS,” she concluded.