Bimekizumab efficacy & safety versus risankizumab to 24 weeks in patients with psoriatic arthritis and concomitant moderate-to-severe psoriasis: An exploratory analysis of the BE BOLD study

Introduction: In patients (pts) with psoriatic arthritis (PsA) in the BE BOLD study, bimekizumab (BKZ; IL-17A/F inhibitor) reported superiority for the joint-focused primary endpoint (≥50% improvement from baseline [BL] in American College of Rheumatology response criteria [ACR50]) compared with risankizumab (RZB; IL-23 inhibitor) at Week (Wk) 16 (49.1% vs 38.4%, p<0.01), and comparable safety.1,2 Pts with PsA who have both joint and skin symptoms have a higher disease burden than those with joint symptoms alone.3 This exploratory analysis evaluated efficacy and safety of BKZ vs RZB in pts with PsA and concomitant moderate-to-severe psoriasis (mod-sev PSO). Procedure/study: BE BOLD was a 24-wk double-blinded phase 3b study in pts ≥18 with PsA (biologic-naïve or inadequate responders/intolerant to 1 prior TNF inhibitor).1,2 We report data in pts with PsA and mod-sev PSO (BSA≥10%, IGA≥3, and PASI≥12), who received BKZ 320mg or RZB 150mg. Final dose in both arms was at Wk16, in line with labels (BKZ: Q4W to Wk16, then Q8W; RZB: Wk0, Wk4, then Q12W). Outcomes reported to Wk24 (non-responder imputation); TEAEs assessed to end of study. Results: Of 553 randomized pts, 277/276 received BKZ/RZB; of these, 29/277 (10.5%) and 31/276 (11.2%) had concomitant mod-sev PSO. A numerically higher number of pts with PsA and mod-sev PSO receiving BKZ vs RZB achieved ACR50 at Wk4 (27.6% [BKZ] vs 9.7% [RZB]), which improved further to Wk24 (65.5% vs 41.9%). A higher number of BKZ-treated pts achieved PASI100 at Wk4 (20.7% vs 3.2%) and at Wk24 (58.6% vs 45.2%). Although ACR50+PASI100 responses were similar between BKZ and RZB at Wk4 (3.4% vs 3.2%), BKZ resulted in a higher response than RZB by Wk24 (44.8% vs 25.8%). ≥1 TEAE was reported in 15/29 (51.7%) BKZ- and 13/31 (41.9%) RZB-treated pts. Serious TEAEs (BKZ: 0%; RZB: 3.2%), severe TEAEs (BKZ: 3.4%; RZB: 0%), and study discontinuations due to TEAEs (BKZ: 3.4%; RZB: 0%) were low. Conclusion: In pts with PsA and concomitant mod-sev PSO, dual inhibition of IL-17A/F with BKZ at the label dose led to a greater number of pts achieving joint and skin outcomes than with RZB, as rapid as Wk4, and at Wk24, potentially due to BKZ’s more comprehensive inflammation control via inhibition of IL-23-dependent and -independent IL-17A/F. In this exploratory analysis, safety was comparable between treatments, with no new safety signals identified for BKZ.