Effectiveness of biologics for endoscopic healing in patients with isolated proximal small bowel Crohn's disease.

Background: Endoscopic healing (EH) is a key therapeutic target in Crohn's disease (CD). Proximal small bowel (SB) lesions in patients with CD are associated with a significant risk of strictures and bowel resection. Assessing SB in patients with CD is necessary because of its significant therapeutic implications. The advent of biologic therapies, including infliximab, ustekinumab, and vedolizumab, has significantly altered CD treatment. However, data on the efficacy of biologics in achieving EH, specifically in the proximal SB of patients with CD, remain limited.

Aim: To assess the effectiveness of biologics for EH in patients with jejunal and/or proximal ileal CD.

Methods: Between 2017 and 2023, we retrospectively included 110 consecutive patients with isolated proximal SB CD, identified through baseline balloon-assisted enteroscopy. These patients completed 1-year of treatment with infliximab, ustekinumab, or vedolizumab, and underwent a second balloon-assisted enteroscopy at 1 year. Complete EH was defined as a modified Simple Endoscopic Score for CD (SES-CD) of < 3, while EH of the jejunum and proximal ileum was defined as a segmental modified SES-CD of 0.

Results: In total, 64 patients were treated with infliximab, 28 with ustekinumab, and 18 with vedolizumab. The complete EH rate at 1 year was 20.9% (23/110), with 29.6% (19/64) for infliximab, 10.7% (3/28) for ustekinumab, and 5.5% (1/18) for vedolizumab. The median modified SES-CD significantly decreased compared to baseline [5 (2-8) 8 (6-9), < 0.001]. The jejunal and proximal ileal EH rates at 1 year were 30.8% (12/39) and 15.5% (16/103), respectively. Multiple logistic regression analysis showed that stricturing or penetrating disease [odds ratio (OR) = 0.261, 95%CI: 0.087-0.778, = 0.016], prior exposure to biologics (OR = 0.080, 95%CI: 0.010-0.674, = 0.020), and moderate-to-severe endoscopic disease (OR = 0.277, 95%CI: 0.093-0.829, = 0.022) were associated with a lower likelihood of achieving EH at 1 year.

Conclusion: Only 20.9% of patients with isolated proximal SB CD achieved complete EH after 1 year of biologic therapy.