Originator versus biosimilar adalimumab in hidradenitis suppurativa: a real-world cohort study

BACKGROUND AND OBJECTIVES: Comparative real-world data on originator and biosimilar adalimumab in hidradenitis suppurativa (HS) are limited. We compared effectiveness, persistence, and safety of originator (ADL-O) versus three biosimilars (ADL-B1, ADL-B2, ADL-B3) in routine care. RESEARCH DESIGN AND METHODS: Retrospective cohort of 146 biologic-naive HS patients initiating adalimumab (January 2020-November 2025) at three tertiary centers in Turkiye. Primary outcomes were Week-12 HiSCR50 and IHS4-55 responses, compared using overlap weighting. Persistence was assessed by 24-week restricted mean survival time (RMST). Safety was summarized descriptively. RESULTS: = 118) showed no evidence of differential effectiveness: HiSCR50 RR 1.05 (95% CI 0.78-1.42); IHS4-55 RR 1.07 (95% CI 0.76-1.52). Inclusion of ADL-B3 as a sensitivity analysis did not alter the findings. Among Week-52 evaluable ADL-O and ADL-B1 patients, HiSCR50 was 68.8% in both groups. Product-level 24-week RMST was 23.4 versus 22.3 weeks (difference -1.1 weeks, 95% CI - 2.7 to 0.5). Safety comparisons were descriptive given limited sample size. CONCLUSIONS: No statistically significant difference in short-term effectiveness was detected between originator and biosimilar adalimumab in HS. The findings reflect absence of evidence for a difference rather than equivalence. Larger prospective studies with immunogenicity assessment are needed.