The US FDA has approved a single-injection, once-monthly maintenance regimen of mirikizumab-mrkz (Omvoh) for adults with moderately to severely active ulcerative colitis, Eli Lilly and Company announced October 27, 2025. The new 200 mg/2 mL subcutaneous formulation replaces the previously approved two-injection maintenance regimen.1
This marks the third FDA approval for mirikizumab in 2025, following approvals for Crohn disease and a citrate-free formulation. The single-injection maintenance dose will be available in the US via prefilled pen or prefilled syringe in early 2026.1
"In clinical practice, we see that simplifying maintenance treatment can make a difference in the overall patient experience," Miguel Regueiro, MD, a board-certified gastroenterologist specializing in inflammatory bowel disease, stated in the announcement.1 "A single monthly injection of Omvoh gives patients a regimen that's easier to manage alongside the unpredictability of living with ulcerative colitis."
Treatment with mirikizumab for ulcerative colitis begins with 300 mg intravenous infusions every four weeks for a total of 3 infusions. At week 12, patients transition to subcutaneous self-injection every four weeks for maintenance treatment.1
What This Means for Primary Care Physicians
- Simplified maintenance: Once-monthly single injection may improve adherence for adults who respond to induction therapy.
- Care coordination: Confirm timing of the transition from induction (week 12) to maintenance and ensure patients are trained for at-home administration.
- Safety monitoring: Evaluate for infection risk and liver-enzyme elevations; review vaccination plans and avoid live vaccines near treatment.
- Clinical context: Mirikizumab-mrkz now spans UC and Crohn disease indications, with emerging evidence for patient-reported outcomes, such as bowel-urgency improvement.
The simplified dosing comes as new data demonstrate the effectiveness of mirikizumab in addressing bowel urgency, one of the most challenging symptoms for patients with ulcerative colitis. Results from the phase 3b LUCENT-URGE study, presented at the American College of Gastroenterology Annual Scientific Meeting in October 2025, showed that patients experienced a 55% reduction in daily episodes of bowel urgency from baseline by week 12.2
"For many people with ulcerative colitis, the unpredictable and immediate need to find a restroom can be stressful and disrupt everyday activities, often forcing them to map restroom locations or to avoid important events," David Rubin, MD, professor of medicine and director of the Inflammatory Bowel Disease Center at the University of Chicago Medicine, stated in a news release.2 "These data build on prior Phase 3 and long-term results demonstrating Omvoh can reduce bowel urgency and help people regain control over a symptom that has often dictated their daily life."
By week 28, bowel urgency severity was reduced by 52%, and nearly one-third of patients were able to delay using the restroom for at least 15 minutes after feeling urgency, up from 4% at baseline. LUCENT-URGE was the first study in inflammatory bowel disease to assess bowel urgency across three measures—severity, frequency and stool deferral time—reflecting the spectrum of its burden on patients.2
Evidence supporting approval. The single-injection approval is based on results from a phase 1 study comparing one 200 mg/2 mL subcutaneous injection to two 100 mg/1 mL injections in participants. The study confirmed that mirikizumab single-injection is bioequivalent to the previously approved two-injection regimen, according to the company announcement.1
"People living with the constant discomfort and disruption caused by the symptoms of ulcerative colitis need treatments that offer the potential to achieve lasting remission and a convenient dosing option that fits easily into their lives," George Salem, MD, director of Crohn's and Colitis Center at OU Health, stated.1 "With this approval, patients who respond to induction therapy with Omvoh can continue maintenance therapy with the convenience of just one injection each month—delivering the same proven results with fewer injections."
Expanding Therapeutic Options for Inflammatory Bowel Disease
The mechanism of action of mirikizumab targets interleukin-23p19 (IL-23p19), a protein involved in intestinal inflammation. The drug received its first FDA approval in October 2023 as a first-in-class treatment for moderately to severely active ulcerative colitis. In January 2025, the FDA expanded the indication to include moderately to severely active Crohn disease in adults, making it the first biologic treatment in more than 15 years to have disclosed two-year phase 3 efficacy data in Crohn disease at the time of approval.3
For Crohn disease, data from the phase 3 VIVID-1 trial demonstrated that 53% of patients treated with mirikizumab achieved clinical remission at one year compared to 36% of those receiving placebo. Additionally, 46% of mirikizumab-treated patients showed endoscopic response at one year versus 23% on placebo. An ongoing open-label extension study, VIVID-2, indicated that nearly 90% of patients who achieved both clinical remission and endoscopic response at one year maintained clinical remission with two years of continuous mirikizumab treatment.3
"Many patients with Crohn's disease have tried available therapies and are still seeking a treatment option that can work well for them to help control their disease," Marla Dubinsky, MD, chief of the division of pediatric gastroenterology and nutrition and co-director of the Susan and Leonard Feinstein IBD Clinical Center at Mount Sinai Kravis Children's Hospital, stated in a January 2025 news release.3
The most common adverse events associated with mirikizumab include upper respiratory tract infections, injection site reactions, headache, arthralgia, and elevated liver enzymes.3 The FDA label includes warnings for hypersensitivity reactions, infections, tuberculosis, hepatotoxicity, and immunizations.3 In the LUCENT-URGE study, 5.2% of patients reported a serious adverse event, while 4.7% discontinued treatment due to an adverse event.2
According to the press release, Eli Lilly intends to make the mirikizumab-mrkz injection available in the US in early 2026, in the form of a prefilled pen or syringe.1
References
- Lilly's Omvoh (mirikizumab-mrkz) approved by U.S. FDA as a single-injection maintenance regimen in adults with ulcerative colitis. News release. Eli Lilly and Company. October 27, 2025. Accessed November 5, 2025. https://investor.lilly.com/news-releases/news-release-details/lillys-omvoh-mirikizumab-mrkz-approved-us-fda-single-injection
- Lilly's Omvoh (mirikizumab-mrkz) demonstrated early and sustained improvement in bowel urgency outcomes for patients with ulcerative colitis. News release. Eli Lilly and Company. October 27, 2025. Accessed November 5, 2025. https://investor.lilly.com/news-releases/news-release-details/lillys-omvoh-mirikizumab-mrkz-demonstrated-early-and-sustained
- FDA approves Lilly's mirikizumab-mrkz for Crohn's disease. Patient Care. January 15, 2025. Accessed November 5, 2025. https://www.patientcareonline.com/view/fda-approves-lilly-s-mirikizumab-mrkz-for-crohn-s-disease
