OP35 Efficacy of mirikizumab in comparison to ustekinumab in patients with moderate to severe Crohn’s disease: Results from the phase 3 VIVID 1 study

Abstract Background The primary objective of the VIVID-1 trial (NCT03926130) was to demonstrate efficacy and safety of mirikizumab (miri), a p19-directed anti-IL-23 antibody, compared to placebo (PBO) in patients (pts) with moderate-to-severe Crohn’s disease. Miri demonstrated statistically significant improvements in co-primary and all key secondary endpoints versus (vs) PBO1. Here we present the results of secondary endpoints on the comparisons of miri to ustekinumab (uste), a p40 directed anti-IL-12/IL-23 inhibitor from the Phase 3, randomised, double-blind, double-dummy, active- and PBO-controlled, treat-through (TT) study, VIVID-1 (NCT03926130). Methods Adult pts (N=1065) were randomised 6:3:2 to miri (N=579) 900mg intravenously (IV) every 4 weeks (Q4W) to W12, then 300mg subcutaneously (SC) Q4W to W52, uste (N=287) one ~6 mg/kg IV dose, then 90mg SC Q8W to W52 or PBO (N=199). At W12 PBO responders continued PBO to W52; PBO non-responders received the same blinded miri regimen as described above (IV then SC). Efficacy of miri vs uste was assessed by the proportion of pts achieving endoscopic response and by the proportion of pts achieving clinical remission by Crohn’s Disease Activity Index (CDAI) at W52 (both gated). Additional non-multiplicity-adjusted endpoints included endoscopic remission, corticosteroid-free clinical remission by CDAI, and the composite of CDAI clinical remission and endoscopic response at W52. (Figure 1 for definitions). Results Baseline characteristics were overall balanced across the three treatment groups (table 1). Pts treated with miri achieved all key major secondary endpoints (p<.000001) compared to PBO (Figure 1). Miri achieved non-inferiority to uste for clinical remission by CDAI (p=0.113117) (Figure 1C). Although superiority to uste in endoscopic response was not achieved (p=0.51) (Figure 1A), in biologic failed pts miri demonstrated a numerical trend towards greater response rates compared to uste for endoscopic response and clinical remission by CDAI (Figure 1 B & D). The overall safety profile was consistent with the known safety profile of miri. The proportion of treatment emergent adverse events (TEAE) were similar for miri (78.6%) and uste (77.3%); most common TEAEs were COVID-19, anaemia, arthralgia, headache, upper respiratory tract infection, nasopharyngitis and injection site reaction. Instances of serious adverse events were comparable for miri (10.3%) and uste (10.7%). Conclusion In this phase 3 TT design study, miri achieved non-inferiority to uste for clinical remission by CDAI. In biologic failed pts miri had a numerical trend towards greater response compared to uste in clinical and endoscopic endpoints, with an acceptable safety profile. 1Ferrante et al., submitted to ECCO 2024