Patients who did not achieve clinical response after a 12-week IV induction period with risankizumab may go on to experience remission following an additional 12 weeks of subcutaneous (SC) risankizumab treatment, according to research presented at Digestive Disease Week.

Remo Panaccione, MD, professor of medicine and director of the Inflammatory Bowel Disease Unit at the University of Calgary, presented the results of a study he and colleagues conducted to determine if extended induction benefitted patients with moderately to severely active ulcerative colitis.

Risankizumab, an anti-interleukin (IL) 23p19 monoclonal antibody, had already demonstrated efficacy for moderately to severely active UC in the 12-week phase 3 INSPIRE induction study. Patients who did not achieve clinical response as assessed by Adapted Mayo Score (AMS) at week 12 of INSPIRE were randomized 1:1:1 to extended treatment with 180 mg or 360 mg risankizumab subcutaneously (SC) at weeks 12 and 20 or 1200 mg IV at weeks 12, 16, and 20. Patients who showed clinical response at week 24 on extended SC treatment continued the same dose every 8 weeks over 52 weeks in the phase 3 COMMAND maintenance study. Clinical response and clinical remission per AMS, as well as endoscopic improvement, endoscopic remission, histologic-endoscopic mucosal improvement (HEMI), and safety were evaluated after extended induction at week 24 and at maintenance week 52.

Of 650 patients who received risankizumab induction for 12 weeks, 209 patients who did not reach clinical response as shown by endoscopy received an additional 12 weeks of therapy. At week 24, 56.3%, 57.1%, and 50.0% of patients achieved clinical response and 12.7%, 15.7%, and 8.8% of patients achieved clinical remission on risankizumab 180 mg SC, 360 mg SC, and 1200 mg IV, respectively. Rates of endoscopic improvement, endoscopic remission, and HEMI were similar across these groups. Among the 56 patients treated with 180 mg SC and 44 patients who received 360 mg SC who achieved clinical response at week 24 and continued in COMMAND, 46.4% and 45.3% achieved clinical response, and 17.9% and 22.8% achieved clinical remission at maintenance week 52, respectively. Rates of treatment-emergent adverse events were similar across groups at weeks 24 and 52. No new safety risks were identified.

The researchers concluded that patients who respond to extended induction may continue to observe benefits at week 52. They did not observe additional benefit at week 24 of additional risankizumab IV treatment over initiation of SC treatment, which suggests that the duration of exposure to risankizumab, rather than the dose, may be an important factor in inducing remission among patients with refractory UC.

Reference:

Panaccione R, MelmedG, DrobneD, et al. Abstract 904: Additional risankizumab therapy is effective in patients with moderately to severely active ulcerative colitis who did not achieve clinical response to initial 12-week inducation therapy: an analysis of phase 3 INSPIRE and COMMAND studies. Presented at: Digestive Disease Week, May 20, 2024, Washington, DC.