Mirikizumab, a p19-directed antibody against interleukin-23, was “more effective than placebo in inducing and maintaining clinical remission in patients with moderately to severely active ulcerative colitis,” researchers report. “Opportunistic infection or cancer occurred in a small number of patients treated with mirikizumab.”
Adults with moderately to severely active ulcerative colitis participated in phase 3, randomized, double-blind, placebo-controlled induction and maintenance trials. Mirikizumab 300 mg or placebo was administered intravenously every 4 weeks for 12 weeks in the induction trial. In the maintenance trial, patients who responded to mirikizumab induction therapy were randomized to subcutaneous mirikizumab 200 mg or placebo every 4 weeks for 40 weeks.
Based on primary endpoints of clinical remission at week 12 in the induction trial and at week 40 (at 52 weeks overall) in the maintenance trial, the investigators report: “A total of 1,281 patients underwent randomization in the induction trial, and 544 patients with a response to mirikizumab underwent randomization again in the maintenance trial. Significantly higher percentages of patients in the mirikizumab group than in the placebo group had clinical remission at week 12 of the induction trial (24.2% vs. 13.3%, P <0.001) and at week 40 of the maintenance trial (49.9% vs. 25.1%, P <0.001). The criteria for all the major secondary end points were met in both trials. Adverse events of nasopharyngitis and arthralgia were reported more frequently with mirikizumab than with placebo. Among the 1,217 patients treated with mirikizumab during the controlled and uncontrolled periods (including the open-label extension and maintenance periods) in the two trials, 15 had an opportunistic infection (including 6 with herpes zoster infection) and 8 had cancer (including 3 with colorectal cancer). Among the patients who received placebo in the induction trial, 1 had herpes zoster infection and none had cancer.”