Abstract Background Hidradenitis suppurativa (HS) is a chronic, relapsing, debilitating skin disease characterized by deep‐seated nodules, abscesses and tunnels. Objectives To investigate the efficacy of bimekizumab using International Hidradenitis Suppurativa Severity Score System (IHS4) outcomes in patients with moderate to severe HS in the pooled BE HEARD I and II Phase 3 studies. Methods Patients received (initial/maintenance) bimekizumab 320 mg every 2 weeks (Q2W)/Q2W, bimekizumab Q2W/every 4 weeks (Q4W), bimekizumab Q4W/Q4W or placebo/bimekizumab Q2W. Change from baseline (CfB) in IHS4, IHS4 severity stages and the dichotomous IHS4‐55/75/90/100 (an improvement of at least 55%/75%/90%/100% in IHS4 from baseline) are reported to Week 48. Lesion count data by lesion type are reported to Week48. Results In total, 1014 patients were enrolled across BE HEARD I and II. At baseline, mean (standard deviation SD) IHS4 for bimekizumab‐treated patients ranged from 33.4 (25.4) for bimekizumab Q2W/Q2W to 36.0 (34.0) for bimekizumab Q2W/Q4W versus 30.6 (21.8) for placebo. At Week16, patients receiving bimekizumab demonstrated greater reductions in mean (SD) IHS4 from baseline, ranging from −17.2 (24.8) for bimekizumab Q4W/Q4W to −17.8 (21.1) for bimekizumab Q2W/Q2W versus −6.1 (16.3) for placebo. Proportions of patients with severe HS at baseline ranged from 83.7% (bimekizumab Q2W/Q2W) to 88.4% (bimekizumab Q2W/Q4W) and decreased by ~50% to Week48 across all treatment arms, ranging from 28.6% (placebo/bimekizumab Q2W) to 34.3% (bimekizumab Q2W/Q2W). Proportions of patients with IHS4 = 0 at Week48 ranged from 23.7% (bimekizumab Q2W/Q4W) to 26.7% (placebo/bimekizumab Q2W). At Week16, IHS4‐55, IHS4‐75, IHS4‐90 and IHS4‐100 thresholds were achieved by greater proportions of patients treated with bimekizumab versus placebo, while comparable improvements were seen across treatment arms from Week16 to Week48. At Week16, lesion counts were lower for patients treated with bimekizumab versus placebo, decreasing to comparable numbers across all groups at Week48. Conclusions Bimekizumab‐treated patients showed improvements across IHS4 outcome measures.
Tzellos et al. (2026) studied this question.