MILAN – Secukinumab (Cosentyx) and biosimilar adalimumab-adaz (Hyrimoz) injection proved to have similar efficacy for limiting spinal radiographic progression over a 2-year period in patients with radiographic axial spondyloarthritis (r-axSpA) in the SURPASS study, a phase 3b, randomized controlled trial.
The study, presented at the annual European Congress of Rheumatology, represents the first head-to-head trial comparing the effects of two biologic disease-modifying antirheumatic drugs (bDMARDs) in axSpA. Notably, secukinumab and adalimumab-adaz target different pathways as an interleukin-17A inhibitor and a tumor necrosis factor (TNF) inhibitor, respectively.
Both TNF and IL-17A have been implicated in the pathogenesis of axSpA. Anti-TNF agents and the IL-17A inhibitor secukinumab have demonstrated effectiveness in improving symptoms, signs, and physical function in patients with axSpA and are approved therapies for the disease. However, limited data exist regarding the effect of bDMARDs in slowing radiographic progression, which is a key therapeutic goal in axSpA to prevent irreversible structural damage.
The SURPASS trial, funded by Novartis, enrolled 859 biologic-naive adult patients with moderate to severe r-axSpA. Participants were randomly assigned (1:1:1) to receive secukinumab 150 mg (n = 287), secukinumab 300 mg (n = 286), or adalimumab-adaz 40 mg (n = 286). The primary endpoint was the proportion of patients with no radiographic progression at the 2-year mark (week 104). Radiographic progression was defined as a change from baseline in modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS; range, 0-72) of 0.5 or less. The radiographic assessments were conducted by three independent evaluators who were blinded to treatment and the chronology of images.
Baseline characteristics indicated that the study population (78.5% male; mean age, 42.1 years) had a high risk of radiographic progression. The proportion of patients with no radiographic progression at week 104 was 66.1% in the secukinumab 150-mg arm, 66.9% in the secukinumab 300-mg arm, and 65.6% in the adalimumab-adaz arm. The mean change from baseline in mSASSS was 0.54, 0.55, and 0.72, respectively.
Notably, more than half of the patients (56.9%, 53.8%, and 53.3%, respectively) with at least one syndesmophyte at baseline did not develop new syndesmophytes over the 2-year period. The observed reductions in sacroiliac joint and spinal edema were comparable across all treatment groups. The safety profile of secukinumab and adalimumab-adaz was consistent with their well-established profiles.
Dr. Xenofon Baraliakos
No significant differences were observed between the treatment groups in terms of the primary and secondary endpoints. Study presenter and lead author Xenofon Baraliakos, MD, PhD, medical director of the Rheumatism Centre and professor of internal medicine and rheumatology at Ruhr University Bochum (Germany), stated: “Anti-TNF therapy has been considered the gold-standard treatment for axial spondyloarthritis in terms of slowing or halting radiographic progression. Our aim was to investigate whether other modes of action, such as IL-17 inhibition, achieve the same results. The primary hypothesis was that IL-17 inhibition could be even more effective than TNF blockade. However, our data indicate that secukinumab is at least as good as TNF blockers.
“Several risk factors, including high C-reactive protein [CRP] levels, male gender, high disease activity, and baseline radiographic damage (e.g., presence of syndesmophytes), are associated with structural progression,” Dr. Baraliakos explained. “We performed subgroup analyses and found no differences. This is a positive outcome as it suggests that there is no need to select patients based on either secukinumab or anti-TNF agents.”
When making treatment decisions, other factors must be taken into consideration. “Our study specifically examined radiographic progression. The clinical outcomes, indications, and contraindications for anti-TNF agents and secukinumab differ,” Dr. Baraliakos explained. “For instance, secukinumab may be preferred for patients with psoriasis, while adalimumab is more suitable for those with inflammatory bowel disease. Although these bDMARDs are not interchangeable, they have the same positive effect on radiographic progression.”