ASSOCIATION OF HISTOLOGIC MEASUREMENT WITH ENDOSCOPIC OUTCOMES WITH MIRIKIZUMAB IN PATIENTS WITH MODERATE-TO-SEVERE CROHN'S DISEASE

Introduction We explored the agreement of histologic response and remission with endoscopic outcomes after 12 and 52wks of treatment with miri in a Phase 2 randomized clinical trial (SERENTIY; NCT02891226) in patients with moderate-to-severe CD. Methods Patients were randomized 2:1:1:2 across 4 treatment arms (PBO:200:600:1000mg miri) administered intravenously (IV) Q4W at W0, 4, and 8. The patients were rerandomized at W12: endoscopic improvers received miri either IV (same dose as induction) or 300mg SC; those who did not achieved endoscopic improvement and PBO group continued with miri 1000mg IV from W12 to 52. Biopsies were obtained during endoscopy at W0, 12, and 52 from the edge of the ulcer and the most inflamed mucosa in terminal ileum and 4 colonic segments. Results At Wk12, there was 69.6% agreement between histologic and endoscopic response, and 84.2% agreement between histologic and endoscopic remission. After 52wks of miri treatment, the agreement between histologic and endoscopic response was 62.7%, while the agreement between histologic and endoscopic remission was 70.6% (Table 1). Conclusions Histologic and endoscopic outcomes demonstrated moderate association after both 12 and 52wks of miri treatment. Histologic endpoints, despite the stringent criteria, appear to be more sensitive to change than endoscopic endpoints.