Mirikizumab Sustained Impact on Fatigue in Patients with Moderately to Severely Active Crohn's Disease in the Phase 2 AMAG Study

Background: Fatigue is a burdensome, under-recognized, multidimensional symptom experienced by patients with Crohn's disease (CD). We evaluated the impact of mirikizumab on fatigue and the association between changes in select patient-reported outcomes and clinical measures with changes in fatigue from baseline to week 104 (W104).

Methods: Patients (N = 191) were randomized (2:1:1:2) to receive placebo (PBO), 200 mg, 600 mg, or 1000 mg of mirikizumab, administered intravenously (IV) every 4 weeks at W0, W4, and W8. Patients who achieved ≥1 point improvement in Simple Endoscopic Score for Crohn's Disease (SES-CD) and received mirikizumab at W12 (rerandomized maintenance cohort) were rerandomized to continue induction IV treatment assignment (IV-C) or received 300 mg of mirikizumab subcutaneously (SC) until W52. Nonrandomized maintenance cohort had endoscopic nonimprovers (1000 mg) and PBO patients (PBO/1000 mg) who received 1000 mg of mirikizumab until W52. Subjects from the maintenance period with clinical benefit received 300 mg SC Q4W from W52 to W104. The Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) questionnaire was used to assess fatigue, and the FACIT-F associations were assessed using Pearson correlation coefficient.

Results: At W12, mirikizumab groups reported improved FACIT-F scores compared with PBO, and improvement was maintained through W52 and W104. Changes in FACIT-F at W52 and W104 had strong correlations with changes at the same time point in quality of life (QoL) scores but lacked correlations with changes in inflammatory biomarkers.

Conclusions: Mirikizumab treatment significantly improved fatigue in patients with moderately to severely active CD, which was sustained to W104. The improvement in fatigue was correlated with improvement in clinical measures and was strongly correlated with improvement in QoL.