Mirikizumab as Induction and Maintenance Therapy in Chinese Patients with Ulcerative Colitis: A Subpopulation Analysis of the Randomized, Global Phase 3 LUCENT-1 and LUCENT-2 Trials

BACKGROUND: Mirikizumab, a p19-directed anti-interleukin-23 antibody, demonstrated efficacy in patients with moderately-to-severely active ulcerative colitis in the global phase 3 LUCENT-1 induction (NCT03518086) and LUCENT-2 maintenance (NCT03524092) trials. OBJECTIVE: The aim was to conduct a pre-specified Chinese subpopulation analysis of LUCENT-1 and LUCENT-2. METHODS: In LUCENT-1, patients were randomized 3:1 to mirikizumab 300 mg or placebo intravenously every 4 weeks (Q4W) for 12 weeks. In LUCENT-2, patients with a clinical response to mirikizumab at week 12 of LUCENT-1 were re-randomized 2:1 to mirikizumab 200 mg or placebo via subcutaneous injection Q4W for 40 weeks. The primary endpoint in both trials was clinical remission at study end, defined as a Mayo stool frequency subscore of 0, or 1 with a ≥ 1-point decrease from baseline, rectal bleeding subscore of 0, and an endoscopic subscore of 0 or 1 (excluding friability). RESULTS: Among 183 Chinese patients included in the LUCENT-1 induction trial, clinical remission rates at week 12 were higher with mirikizumab 300 mg (n = 140) versus placebo (n = 43) (18.6% vs. 7.0%; common risk difference 11.5%). Among 80 patients who responded to mirikizumab and underwent randomization again in the LUCENT-2 maintenance trial, clinical remission rates at week 40 were higher with mirikizumab 200 mg (n = 56) versus placebo (n = 24) (50.0% vs. 12.5%; common risk difference 40.4%). During induction and maintenance, the incidence of adverse events was comparable between the mirikizumab and placebo groups. CONCLUSIONS: Mirikizumab was effective and well tolerated in the subpopulation of Chinese patients with moderately-to-severely active ulcerative colitis, consistent with the overall trial population. TRIAL REGISTRATIONS: Clinicaltrials.gov (NCT03518086 and NCT03524092).