SUSTAINED EFFICACY AND SAFETY OF BIMEKIZUMAB IN PATIENTS WITH ACTIVE PSORIATIC ARTHRITIS AND PRIOR INADEQUATE RESPONSE TO TUMOUR NECROSIS FACTOR INHIBITORS: RESULTS FROM THE PHASE 3 BE COMPLETE STUDY AND ITS OPEN-LABEL EXTENSION UP TO 1 YEAR

Background: Bimekizumab (BKZ), a monoclonal IgG1 antibody that selectively inhibits interleukin (IL)‐17F in addition to IL‐17A, has shown superior efficacy to 16 weeks (wks) vs placebo (PBO) and tolerability in patients (pts) with active psoriatic arthritis (PsA) in the phase 3 BE OPTIMAL and BE COMPLETE studies.[ 1,2] Efficacy of BKZ to 52 wks has also been demonstrated in the BE OPTIMAL study of biologic‐naïve pts with PsA.[3] Objectives: To assess long‐term efficacy and safety of BKZ treatment up to 52 wks in pts with active PsA and prior inadequate response or intolerance to tumour necrosis factor inhibitors (TNFi‐IR). Methods: BE COMPLETE (NCT03896581) included a 16‐wk double‐blind, PBO‐controlled period. Wk 16 completers were eligible for entry into BE VITAL (NCT04009499; open‐label extension). BE VITAL included pts from BE OPTIMAL and BE COMPLETE; data here are for pts randomised at baseline (BL [Wk 0]) of BE COMPLETE only, up to 1 yr. Pts were randomised 2:1 to subcutaneous BKZ 160 mg every 4 wks or PBO. At Wk 16, PBO pts switched to BKZ (PBO/ BKZ; received 36 wks of BKZ treatment up to Wk 52). Efficacy data reported are observed case or using non‐responder imputation (binary) or multiple imputation (continuous). The number of treatment‐emergent adverse events (TEAEs) to Wk 52 are reported for pts who received ≥1 dose of BKZ, including pts who switched from PBO to BKZ at Wk 16. Results: 388/400 (97.0%) pts completed Wk 16; 377 (94.3%) entered BE VITAL and 347 (86.8%) completed Wk 52. Improved efficacy responses with BKZ treatment were sustained from Wk 16 to Wk 52 (Table 1). At Wk 52, 51.7% BKZ and 40.6% PBO/BKZ pts achieved American College of Rheumatology (ACR)50. In pts with BL psoriasis (≥3% body surface area), 65.9% BKZ and 60.2% PBO/ BKZ pts achieved Psoriasis Area Severity Index (PASI)100 (complete skin clearance) at Wk 52 (Figure 1). At Wk 52, 47.2% BKZ and 33.1% PBO/BKZ pts achieved minimal disease activity (MDA). To Wk 52, 243/388 (62.6%) pts had ≥1 TEAE whilst receiving BKZ (exposure‐adjusted incidence rate per 100 pt‐years [EAIR/100 PY]: 126.0); 23 (5.9%) pts reported a serious TEAE (7.0/100 PY). Malignancies (excluding non melanomic skin cancers) were reported by 2 (0.7%) pts receiving BKZ (0.77/100PY). Candida infections were reported by 25 (6.4%) pts receiving BKZ (7.7/100 PY); all were reported as mild or moderate by investigators; none were systemic. Two cases of oral candidiasis led to study discontinuation. There was one death (sudden death; pt with history of cardiac events), two adjudicated major adverse cardiac events and no definite or probable adjudicated inflammatory bowel disease. Conclusion: In pts with PsA and TNFi‐IR, BKZ demonstrated sustained clinical efficacy from Wk 16 up to Wk 52. The safety profile was consistent with previous reports.[1‐3] (Table Presented).