About this trial

This Phase 4, single-arm, open-label study will evaluate the effectiveness and safety of mirikizumab combined with surgical curettage and closure in adults with active perianal fistulizing Crohn's disease. Fifty participants with complex draining fistulas will undergo staged surgical management followed by mirikizumab induction and maintenance therapy. The primary endpoint is combined clinical remission and radiologic response at Week 24. Participants will be followed through Week 48.

Eligibility criteria

This trial does not accept healthy volunteers

Qualifiers

Adults ≥18 years

Diagnosis of Crohn disease for at least 3 months

Active draining complex perianal fistula

Able to provide informed consent

Disqualifiers

Rectovaginal fistula

Only low intersphincteric or submucosal fistulas

Severe proctitis preventing surgical closure

Stoma

Trial design

Design model

Single group

Treatments tested in this trial

Mirikizumab
Drug
Mirikizumab is administered as a 900 mg intravenous infusion at Weeks 0, 4, and 8, followed by a 300 mg subcutaneous maintenance injection beginning at Week 12 and every 4 weeks thereafter through the end of the study.
Fistula Tract Curettage and Closure
Procedure/Surgery
Participants undergo an initial examination under anesthesia with fistula tract curettage and seton placement before initiation of mirikizumab therapy. After 8 to 10 weeks of induction therapy, participants undergo a second examination under anesthesia with seton removal, repeat fistula tract curettage, and closure of the internal fistula opening(s).

Treatment groups

50 Participants

are divided into 1 treatment group

Group A: Participants with active perianal fistulizing Crohn diseaseExperimental treatment 2 interventions

Trial outcomes

Primary outcomes

1

Proportion of participants achieving combined clinical remission and radiologic response

Proportion of participants achieving combined clinical remission and radiologic response. Clinical remission is defined as complete closure of all treated external fistula openings without spontaneous drainage or drainage upon gentle finger compression and without development of new fistulas or abscesses greater than 1 cm. Radiologic response is defined using MAGNIFI-CD criteria as greater than 50% reduction in MAGNIFI-CD score together with improvement in fibrosis-to-fluid ratio compared with baseline MRI. The MAGNIFI-CD is an MRI-based composite index that assesses perianal fistulizing Crohn disease activity using six weighted domains, including fistula complexity, tract length, fistula composition, tract enhancement, extension, and inflammatory mass/abscess. Total scores range from 0 to 25, with higher scores indicating greater disease activity and lower scores indicating improvement.

Time frame

Week 24

Secondary outcomes

1

Proportion of participants achieving combined clinical remission and radiologic response

Proportion of participants achieving combined clinical remission and radiologic response. Clinical remission is defined as complete closure of all treated external fistula openings without spontaneous drainage or drainage upon gentle finger compression and without development of new fistulas or abscesses greater than 1 cm. Radiologic response is defined using MAGNIFI-CD criteria as greater than 50% reduction in MAGNIFI-CD score together with improvement in fibrosis-to-fluid ratio compared with baseline MRI. The MAGNIFI-CD is an MRI-based composite index that assesses perianal fistulizing Crohn disease activity using six weighted domains, including fistula complexity, tract length, fistula composition, tract enhancement, extension, and inflammatory mass/abscess. Total scores range from 0 to 25, with higher scores indicating greater disease activity and lower scores indicating improvement.

Time frame

48 week

MIRICURE: Mirikizumab With Curettage and Repair (Closure) for Perianal Fistulizing Crohn's Disease