Secukinumab, an interleukin 17-A inhibitor approved for the treatment of moderate to severe psoriasis, significantly reduced the signs and symptoms of ankylosing spondylitis in two phase III trials, researchers reported Dec. 23 in the New England Journal of Medicine.
The results of the double-blind MEASURE 1 and MEASURE 2 trials extend the positive results of the phase II study, according to Dr. Dominique Baeten of the Academic Medical Center at the University of Amsterdam and his colleagues (N Engl J Med. 2015 Dec 23. doi: 10.1056/NEJMoa1505066).
“Although head-to-head trials would be required to fully assess the efficacy and safety of secukinumab versus TNF-inhibitors, the [20% improvement in Assessment of Spondyloarthritis International Society (ASAS20) response criteria] response rates achieved with secukinumab at week 16 in our studies were similar to those reported in phase III studies of anti-TNF agents in which most of the patients had not received previous anti-TNF therapy (response rates of 58% to 64% at weeks 12 to 24), even though 30% to 40% of the patients in our studies had had no response to previous anti-TNF treatment,” the authors wrote.
“Thus, secukinumab not only is effective in patients who have not received TNF agents previously but also may be effective in patients in whom previous anti-TNF treatment failed,” they added.
In MEASURE 1, 371 patients received intravenous secukinumab (10 mg/kg of body weight) or matched placebo at weeks 0, 2, and 4, followed by subcutaneous secukinumab (150 mg or 75 mg) or matched placebo every 4 weeks starting at week 8.
The study’s primary endpoint of ASAS20 response rates at week 16 were 61%, 60%, and 29% for subcutaneous secukinumab at doses of 150 mg and 75 mg and for placebo, respectively, (P less than .001 for both comparisons with placebo).
In MEASURE 2, 219 patients received subcutaneous secukinumab (150 mg or 75 mg) or matched placebo at baseline; at weeks 1, 2, and 3; and every 4 weeks starting at week 4.
At week 16, patients in the placebo group were randomly reassigned to subcutaneous secukinumab at a dose of 150 mg or 75 mg.
In this trial, ASAS20 rates were 61%, 41%, and 28% for subcutaneous secukinumab at doses of 150 mg and 75 mg and for placebo, respectively (P less than .001 for the 150-mg dose and P = .10 for the 75-mg dose).
The researchers noted that the ineffectiveness of the 75-mg dose in MEASURE 2 suggests that the efficacy of secukinumab at the 75-mg dose in MEASURE 1 may have been due to the greater exposure at week 16 as a result of the intravenous loading regimen, not to the 75-mg subcutaneous maintenance dose.
The safety profile of secukinumab in the present studies was consistent with previous studies of secukinumab for ankylosing spondylitis and moderate-to-severe plaque psoriasis, Dr. Baeten and his associates said.
During the entire treatment period, pooled exposure-adjusted incidence rates of grade 3 or 4 neutropenia, candida infections, and Crohn’s disease were 0.7, 0.9, and 0.7 cases per 100 patient-years, respectively, in secukinumab-treated patients.
Overall, the results suggest that interleukin-17A plays a role in the pathogenesis of ankylosing spondylitis, and they validate inhibition of this cytokine as a potential therapeutic approach, the study authors concluded.
The study was sponsored by Novartis Pharma. Dr. Baeten has received a grant from Novartis to study the impact of IL-17A blockade in experimental models of spondyloarthritis. He also has been a consultant for Novartis for the design and conduct of the secukinumab program in ankylosing spondylitis and psoriatic arthritis.