Risankizumab for Refractory Perianal Fistulizing Crohn's Disease

Prior treatment

• Patients who are refractory to three or more prior lines of advanced therapy
• Patients who are intolerant to two or more prior lines of advanced therapy
• Patients previously treated with darvadstrocel
• Patients receiving systemic steroids
• Patients requiring new treatment with immunomodulators or advanced therapies during the screening period
• Patients with concomitant uncontrolled liver disease, hematologic disease, gastrointestinal disease (excluding Crohn's disease), endocrine disease, pulmonary disease, cardiac disease, neurological disease, psychiatric disease, brain disease, or active infection
• Patients who underwent major surgery or suffered severe trauma within the past 6 months
• Patients who showed persistent positivity for HBsAg and HBV-PCR, or seropositivity for HCV and quantitative HCV-PCR within 6 months prior to the start of the screening period
• Patients who received a live vaccine within 4 weeks prior to the start of risankizumab administration

Other illness

• Patients with a rectovaginal fistula at baseline (excluding past rectovaginal fistulas)
• Patients with a history of risankizumab, mirikizumab, or guselkumab administration
• Patients with disease activity (CDAI) \> 400
• Patients with a history of malignancy (excluding carcinoma in situ)
• Patients with active tuberculosis

Other

• Patients with severe rectal and/or anal stricture and/or severe proctitis (defined as the presence of large ulcers exceeding 0.5 cm in the rectum)
• Patients with abscesses or fluid collections exceeding 2 cm
• Patients for whom MRI is contraindicated
• Patients with a colostomy or ileostomy
• Patients undergoing cytapheresis
• Patients who are breastfeeding, pregnant, or may be pregnant, or who plan to become pregnant during the study period
• Other patients deemed inappropriate for trial participation by the principal/ sub-investigator responsible

• 15 years of age or older
• Patients with an MRI-confirmed perianal fistula due to Crohn's disease
• Patients with a draining anal fistula (maximum of 2 internal openings and maximum of 3 external openings) persisting for at least 2 weeks
• Patients who have experienced inadequate response, diminished response, or intolerance to one or more of the following treatments in the past:
  • ① Antibiotics (ciprofloxacin or metronidazole): Treatment lasting one month or longer.
  • ② Immunomodulators (azathioprine, 6-mercaptopurine, or methotrexate): Treatment for 3 months or longer.
  • ③ Advanced therapies (infliximab, adalimumab, vedolizumab, ustekinumab, and upadacitinib): Standard therapy administered for 14 weeks or longer as induction or maintenance therapy.
• Patients who can agree to removal of the perianal seton by week 20 (week 20 ± 1 week) of administration, if patients already have setons inserted.
• Patients with draining fistulas that were drained at least 6 weeks prior to enrollment.
• Patients who have received a sufficient explanation regarding participation in this study, understood it fully, and provided their voluntary written consent, or patients whose legal representative received a sufficient explanation regarding participation in this study, understood it fully, and provided their voluntary written assent, if participating hospital/clinic requires.