Initial findings from the ongoing VIVID-2 open-label extension (OLE) study comprising week 52 endoscopic responders from the phase III VIVID-1 trial demonstrate the long-term clinical and endoscopic efficacy of the selective anti-interleukin-23p19 monoclonal antibody mirikizumab for the treatment of moderate-to-severe active Crohn’s disease (CD).

“High maintenance rates of response and remission were observed after 2 years on mirikizumab therapy,” noted the investigators, led by Dr Edward Barnes from the University of North Carolina School of Medicine, Chapel Hill, North Carolina, US, in their presentation at CCC 2025.

In the overall analysis, using modified nonresponders imputation (mNRI), 81.8 percent of participants maintained endoscopic response, 54.9 percent achieved endoscopic remission, and 79 percent achieved clinical remission as per the Crohn’s Disease Activity Index (CDAI) at week 104. Using the observed case (OC) approach, the corresponding rates were 87.6, 58.7, and 84.7 percent, respectively.

The treatment effect was generally similar between individuals with and without prior biologic failure across endoscopic and clinical outcomes, be it in the mNRI or the OC analysis, the researchers noted.

Endoscopic remission was sustained at week 104 in three-quarters (72.5 percent [mNRI] and 78.6 percent [OC]) of patients who achieved endoscopic remission by the end of VIVID-1. A third of participants (33.3 percent and 35.4 percent, respectively) who have not achieved endoscopic remission at week 52 were able to achieve endoscopic remission at this timepoint.

At week 104, 86.9 percent (mNRI) and 92.9 percent (OC) of patients who were already in clinical remission by end of VIVID-1 had sustained clinical remission as per CDAI; over 50 percent (55.8 percent and 60.8 percent, respectively) of those who were not in clinical remission at week 52 were able to achieve clinical remission. [CCC 2025, abstract P031]

According to Barnes and colleagues, the percentages of patients who achieved remission during the second year were meaningful.

The combined clinical remission and endoscopic response rates were 78.3 percent and 83.8 percent in the respective mNRI and OC analyses. The corresponding corticosteroid-free clinical remission rates were 86.5 percent and 92.6 percent.

Safety data corresponded with the known safety profile of mirikizumab. [Lancet 2024;404:2423-2436; N Engl J Med 2023;388:2444-2455] There were low incidences of severe treatment-emergent adverse events (AEs; 3.4 percent), serious AEs (6.8 percent), and treatment discontinuations due to an AE (0.8 percent). There were no deaths.

In a nutshell

The VIVID-2 OLE study comprised 251 individuals (mean age 36.5 years, 57 percent men) who transitioned from IV mirikizumab 900 mg Q4W (blinded induction phase [week 0?12]) to SC mirikizumab 300 mg Q4W (blinded maintenance phase [week 12?52]) in the 52-week VIVID-1 trial. The same SC mirikizumab dose was used in VIVID-2.

Mean disease duration was 8 years. CD was mostly located in both the ileum and colon (51.4 percent). Mean CDAI was 81.8. Mean Simple Endoscopic Score for Crohn’s Disease was 6.5.

“[Taken together, the] results among endoscopic responders at week 52 of VIVID-1 demonstrate the long-term clinical and endoscopic efficacy of mirikizumab in adults with moderate-to-severe active CD, with or without prior biologic failure,” said the researchers.

After 2 years of mirikizumab treatment, maintenance rates were high, over a third of week 52 endoscopic responders were able to achieve endoscopic remission, and ~90 percent of endoscopic responders who were in corticosteroid-free clinical remission at week 52 remained in remission, they said.

The US FDA has recently approved mirikizumab for the treatment of moderate-to-severe active CD, as well as for moderate-to-severe active ulcerative colitis.