Bimekizumab treatment in patients with active axial spondyloarthritis: 52-week efficacy and safety from the randomised parallel phase 3 BE MOBILE 1 and BE MOBILE 2 studies.

OBJECTIVES: Bimekizumab (BKZ), a monoclonal IgG1 antibody that selectively inhibits interleukin (IL)-17F in addition to IL-17A, has demonstrated superior efficacy versus placebo in patients with non-radiographic (nr-) and radiographic (r-) axial spondyloarthritis (axSpA) at Week 16. Here, the objective is to report the efficacy and safety of BKZ at Week 52. METHODS: BE MOBILE 1 (nr-axSpA; NCT03928704) and BE MOBILE 2 (r-axSpA; NCT03928743) comprised a 16-week, double-blind, placebo-controlled period, then a 36-week maintenance period. From Week 16, all patients received subcutaneous BKZ 160 mg every 4 weeks. RESULTS: Improvements versus placebo in Assessment of SpondyloArthritis International Society ≥40% response (primary endpoint), Ankylosing Spondylitis Disease Activity Score, high-sensitivity C-reactive protein levels and MRI inflammation of the sacroiliac joints/spine at Week 16 were sustained to Week 52 in BKZ-randomised patients. At Week 52, responses of patients switching from placebo to BKZ at Week 16 were comparable to BKZ-randomised patients. At Week 52, ≥1 treatment-emergent adverse events (TEAEs) were reported in 183 (75.0%) and 249 (75.5%) patients with nr-axSpA and r-axSpA, respectively. Serious TEAEs occurred in 9 (3.7%) patients with nr-axSpA and 20 (6.1%) patients with r-axSpA. Oral candidiasis was the most frequent fungal infection (nr-axSpA: 18 (7.4%); r-axSpA: 20 (6.1%)). Uveitis occurred in three (1.2%) and seven (2.1%) patients with nr-axSpA and r-axSpA, and inflammatory bowel disease in two (0.8%) and three (0.9%). CONCLUSIONS: At Week 52, dual inhibition of IL-17A and IL-17F with BKZ resulted in sustained efficacy across the axSpA spectrum; the safety profile was consistent with the known safety of BKZ. TRIAL REGISTRATION NUMBER: NCT03928704; NCT03928743.

Efficacy and safety of bimekizumab in axial spondyloarthritis: results of two parallel phase 3 randomised controlled trials.

OBJECTIVES: Axial spondyloarthritis (axSpA) is a complex disease with diverse manifestations, for which new treatment options are warranted. BE MOBILE 1 (non-radiographic (nr)-axSpA) and BE MOBILE 2 (radiographic axSpA (r-axSpA)) are double-blind, phase 3 trials designed to evaluate efficacy and safety of bimekizumab, a novel dual interleukin (IL)-17A and IL-17F inhibitor, across the axSpA spectrum. METHODS: In parallel 52-week trials, patients with active disease were randomised 1:1 (nr-axSpA) or 2:1 (r-axSpA) to bimekizumab 160 mg every 4 weeks:placebo. From week 16, all patients received bimekizumab 160 mg every 4 weeks. Primary (Assessment of SpondyloArthritis international Society ≥40% improvement (ASAS40)) and secondary endpoints were assessed at week 16. Here, efficacy and treatment-emergent adverse events (TEAEs) are reported up to week 24. RESULTS: 254 patients with nr-axSpA and 332 with r-axSpA were randomised. At week 16, primary (ASAS40, nr-axSpA: 47.7% bimekizumab vs 21.4% placebo; r-axSpA: 44.8% vs 22.5%; p<0.001) and all ranked secondary endpoints were met in both trials. ASAS40 responses were similar across TNFi-naïve and TNFi-inadequate responder patients. Improvements were observed in Ankylosing Spondylitis Disease Activity Score (ASDAS) states and objective measures of inflammation, including high-sensitivity C-reactive protein (hs-CRP) and MRI of the sacroiliac joints and spine. Most frequent TEAEs with bimekizumab (>3%) included nasopharyngitis, upper respiratory tract infection, pharyngitis, diarrhoea, headache and oral candidiasis. More fungal infections (all localised) were observed with bimekizumab vs placebo; no major adverse cardiovascular events (MACE) or active tuberculosis were reported. Incidence of uveitis and adjudicated inflammatory bowel disease was low. CONCLUSIONS: Dual inhibition of IL-17A and IL-17F with bimekizumab resulted in significant and rapid improvements in efficacy outcomes vs placebo and was well tolerated in patients with nr-axSpA and r-axSpA.

Safety and Efficacy of Bimekizumab in Patients With Active Ankylosing Spondylitis: Three-Year Results From a Phase IIb Randomized Controlled Trial and Its Open-Label Extension Study.

OBJECTIVE: To assess the long-term safety, tolerability, and efficacy of bimekizumab in patients with active ankylosing spondylitis (AS). METHODS: Patients with active AS who completed the dose-ranging, 48-week BE AGILE randomized controlled trial were eligible to participate in an open-label extension (OLE) study, in which patients received 160 mg of bimekizumab every 4 weeks. We present the safety and efficacy results through 156 weeks. Missing efficacy data were imputed using nonresponder imputation analysis for binary outcomes and multiple imputation for continuous outcomes. RESULTS: From weeks 0-156, 280 of 303 patients (exposure-adjusted incidence rate 141.0 per 100 patient-years) experienced ≥1 treatment-emergent adverse event; the most frequent adverse events were nasopharyngitis (8.1 per 100 patient-years) and upper respiratory tract infection (5.0 per 100 patient-years). Additionally, 67 of 303 patients (9.8 per 100 patient-years) had mild to moderate localized fungal infections (28 of 303 patients had Candida infections [3.7 per 100 patient-years] and 23 of 303 patients had oral candidiasis [3.0 per 100 patient-years]), 10 patients had serious infections (1.3 per 100 patient-years), and no cases of active tuberculosis were reported. Active inflammatory bowel disease (1.1 per 100 patient-years), anterior uveitis (0.7 per 100 patient-years), and adjudicated major adverse cardiovascular events (0.3 per 100 patient-years) were infrequent. The efficacy of bimekizumab treatment demonstrated at week 48 was sustained in the OLE study. At week 156, nonresponder imputation analysis showed that 53.7% of patients (72.6% of observed cases) met the Assessment of SpondyloArthritis international Society criteria for 40% improvement and 28.0% of patients (37.9% of observed cases) achieved partial remission; Ankylosing Spondylitis Disease Activity Scores were reduced from baseline (mean ± SEM 3.9 ± 0.1) to week 48 (2.1 ± 0.1) and week 156 (1.9 ± 0.1) (multiple imputation). Patients showed sustained improvements in pain, fatigue, physical function, and health-related quality of life. CONCLUSION: The safety profile of bimekizumab was found to be consistent with previously demonstrated findings, and no new safety signals were identified. The efficacy of bimekizumab in patients with AS was sustained through 3 years of treatment.