Abstract Background Ustekinumab, a monoclonal antibody targeting the p40 subunit of interleukin-12 and 23, is an established treatment for moderate-to-severe Crohn’s disease (CD). Wezenla, a biosimilar to originator ustekinumab (Stelara), has demonstrated analytical and pharmacokinetic equivalence, but real-world data on its safety and effectiveness are limited. This study aimed to describe induction outcomes in a group of patients with CD starting on Wezenla. Methods A single centre prospective observational cohort study of patients with CD initiated on biosimilar ustekinumab (Wezenla) was conducted. Data was collected on consecutive patients at baseline and week 16, including disease activity (modified Harvey-Bradshaw Index (mHBI)), quality of life (IBD-Control questionnaire), and inflammatory biomarkers (C-reactive protein (CRP) and faecal calprotectin). Results A total of 37 patients were initiated on Wezenla, with 36 remaining on treatment at the end of the 16 week induction period (one discontinued due to primary non-response). The summary demographics are 46% male, median (IQR) age at initiation was 45 (33-61) years and the median duration of CD at starting ustekinumab was 7 (2-17) years. 16% of patients were also on corticosteroids at initiation. 46% had never smoked, 46% were ex-smokers and 8% were current smokers. 11% of patients had perianal disease. 49% of patients were biologic naïve, 51% of patients had previously been on anti-TNF therapy (infliximab, adalimumab or golimumab) and 8% had been on vedolizumab. All those exposed to vedolizumab had also been on an anti-TNF medication. Comparison of baseline and week 16 results indicate Wezenla improved clinical disease activity scores and biomarkers. Median mHBI at baseline was 5 (2-8) which reduced to 2.5 (1-6) after 16 weeks (Figure 1A). 83% of patients remaining on ustekinumab were in remission or had mild clinical disease activity at week 16. CRP and faecal calprotectin reduced from baseline to week 16 (Figure 1B and 1C). Patient-reported outcome measures showed improvements with the median IBD-Control-8 subscore increasing from 7 (3-12) at baseline to 12 (7-15) following induction and IBD-Control-VAS increasing from 50 (40-70) to 80 (60-90). Conclusion Wezenla appears to show good induction outcomes in this small, real-world sample of patients with CD. Data collection will be ongoing with the aim of comparing real-world safety and effectiveness of Wezenla with originator ustekinumab. Conflict of interest: Mr. Elms, Charles: No conflict of interest Young, David: Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational event attendance: Galapagos Biotech Limited, Takeda UK Ltd, Bristol-Myers Squibb and AbbVie Ltd. Support for attending meetings and/or travel: Galapagos Biotech Limited, Tillotts Pharma UK. Ganeshamoorthy, Evangeline: No conflict of interest Gwiggner, Marcus: No conflict of interest Cummings, Fraser: No conflict of interest
Elms et al. (2026) studied this question.