U.S. FDA approves single-dose formulation of mirikizumab to treat ulcerative colitis

The U.S. Food and Drug Administration (FDA) has approvedMirikizumab (Mirikizumab)-Omvoh as a single-injection once-monthly maintenance regimen for adults with ulcerative colitis. Eli Lilly announced on October 27, 2025 that the approval was based on the results of a Phase 1 study comparing 1200mg/2mL subcutaneous injection with 2100mg/1mL injection. The study confirmed the bioequivalence of the new 1-dose treatment to the previously approved 2-dose regimen.

In clinical practice, we see that streamlining maintenance therapy can change the overall patient experience. Monthly injections of militizumab give patients a more manageable treatment regimen while adding to the unpredictability of life with ulcerative colitis.

The Phase 1 study upon which this approval was based is 1 of 3 unnamed Phase 1 trials designed to evaluate the pharmacokinetics and safety of original and single-dose formulations of militizumab. The researchers included apparently healthy patients aged 18-65 years with a body mass index of 18-34kg/m2 (inclusive). Patients were excluded if they had a severe allergic reaction to militizumab or humanized monoclonal antibodies, had abnormal blood pressure, pulse rate, or body temperature, or intended to use over-the-counter or prescription medications within 7 days before dosing. 2

A total of 396 patients were enrolled and randomly assigned to original or 1 dose of militizumab. Ultimately, 199 patients received the original dose and 197 received the 1-dose formulation. The primary endpoint of bioequivalence between the 2 doses was met as the geometric LSM ratio was within the prespecified equivalence limits of 0.8 and 1.25. Furthermore, the mean serum concentration profiles were similar, indicating no significant differences between the two formulations.

Milizumab was first approved in October 2023 as an infusion (300mg/15mL) or injection (100mg/mL) for ulcerative colitis. The approval was based on results from the LUCENT program, which consisted of two randomized, double-blind, placebo-controlled Phase 3 trials. Since then, militizumab has been approved in 45 countries.

People suffering from ongoing discomfort and confusion caused by ulcerative colitis symptoms need treatments that have the potential to achieve lasting relief and offer a convenient dosing option that can be easily integrated into their lives. With this approval, patients who respond to militizumab induction therapy can continue maintenance therapy with just one monthly injection to achieve the same proven results with fewer injections.

Reference materials:https://www.hcplive.com/view/fda-approves-single-dose-formulation-of-mirikizumab-mrkz-for-ulcerative-colitis