Intravenous secukinumab achieved a higher Assessment of SpondyloArthritis International Society 40 response rate at week 16 compared with placebo, with sustained efficacy through week 52, according to a recent study.

In the randomized, double-blind, placebo-controlled phase III INVIGORATE-1 trial, published in Arthritis & Rheumatology, researchers assessed the safety and efficacy of intravenous (IV) secukinumab in patients with active axial spondyloarthritis (axSpA). The researchers, led by Atul Deodhar, of the Oregon Health and Science University, enrolled 526 patients who were randomly assigned 1:1 to receive IV secukinumab (6 mg/kg loading dose followed by 3 mg/kg every 4 weeks) or IV placebo for 16 weeks. At week 16, patients in the placebo group switched to IV secukinumab (3 mg/kg every 4 weeks), while those in the secukinumab group continued treatment through week 52. The primary endpoint was the proportion of patients achieving an Assessment of SpondyloArthritis International Society 40 (ASAS40) response at week 16—with secondary endpoints including Ankylosing Spondylitis Disease Activity Score–C-reactive protein (ASDAS-CRP) major improvement; Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) change from baseline; ASAS5/6 response; and measures of function, quality of life, and inflammation.

At week 16, 40.9% of the patients receiving IV secukinumab achieved an ASAS40 response compared with 22.9% of those receiving placebo (P < .0001). All secondary endpoints were met, with significantly greater improvements in BASDAI (–2.70 vs –1.69, P < .0001), ASDAS-CRP major improvement (27.7% vs 7.6%, P < .0001), and ASAS5/6 response (43.9% vs 21.8%, P < .0001). By week 24, patients who switched from placebo to secukinumab achieved ASAS40 response rates comparable to those initially assigned to secukinumab. Response rates were maintained through week 52, with 66.8% of patients in the secukinumab group and 74.9% of those in the placebo-secukinumab group achieving ASAS40 at week 52 (observed data). Functional and quality-of-life improvements, including Bath Ankylosing Spondylitis Functional Index and Ankylosing Spondylitis Quality of Life, were also sustained.

Safety outcomes were consistent with prior findings on subcutaneous secukinumab. Through week 16, treatment-emergent adverse events (TEAEs) were reported in 38.6% and 39.1% of patients receiving secukinumab and placebo, respectively. The most frequent TEAEs included COVID-19 infections, diarrhea, nasopharyngitis, and upper respiratory tract infections. One death caused by suspected myocardial infarction was reported but was not deemed related to the study drug. No new or unexpected safety signals were observed.

Certain limitations of the study should be considered. INVIGORATE-1 was a phase III trial evaluating IV secukinumab for axSpA but did not include a direct comparison with the subcutaneous formulation. Therefore, caution is warranted when comparing these findings with studies assessing subcutaneous secukinumab for axSpA.

This study indicated that IV secukinumab demonstrated sustained efficacy in reducing disease activity in axSpA, with a safety profile consistent with prior research on subcutaneous secukinumab.

Full disclosures can be found in the published study.