[Association between vedolizumab levels and clinical outcomes in pouchitis].

BACKGROUND

Pouchitis is the most common complication in patients with ulcerative colitis (UC) following ileal pouch-anal anastomosis (IPAA). Vedolizumab (VDZ) is an effective therapy for chronic antibiotic-refractory pouchitis (CARP) and Crohn's-like disease of the pouch (CLDP). We aimed to assess the association between serum VDZ levels and pouchitis outcomes.

METHODS

This single-center retrospective study was conducted at a tertiary hospital, evaluating patients who underwent IPAA and were treated with postoperative VDZ treatment for CARP or CLDP between October 2015 and January 2020. The primary outcomes were clinical remission rates at weeks 14 and 52 of VDZ therapy.

RESULTS

Nineteen UC patients (13 males; mean age 53.8±4.7 years) who underwent total proctocolectomy with IPAA and were treated with VDZ for CARP or CLDP were included. At week 52, steroid-free clinical remission rates significantly increased to 52.6%, compared to 10.5% at baseline (p=0.01). Endoscopic remission rates during maintenance were 47%, compared to 21% at baseline (p=0.01). Higher mean serum VDZ trough levels at weeks 22 to 52 were significantly associated with clinical remission at week 52 (14.6±1.35 vs. 4.4±2 mcg/ml, p=0.015).

CONCLUSIONS

VDZ is an effective therapy for CARP and CLDP, significantly improving clinical and endoscopic remission rates. Higher maintenance serum VDZ levels were associated with clinical remission, suggesting that therapeutic drug monitoring could optimize dosing, improve outcomes, and prevent unnecessary therapy. Future studies should identify the specific therapeutic window required to achieve remission.