TOPLINE:

In patients with active ulcerative colitis (UC) who initiated vedolizumab, loss of vedolizumab in stool samples was noted in more than 75% of patients, with higher rates of drug loss seen in those with more severe and extensive disease.

METHODOLOGY:

• Researchers conducted a phase 4 study to assess the faecal loss of vedolizumab and its effect on serum drug levels, outcomes, and responses in patients with UC receiving vedolizumab induction therapy.
• They included 36 patients (median age, 35 years; 64% men) with moderate-to-severe UC, defined as having a Simple Clinical Colitis Activity Index (SCCAI) score > 5 at screening, elevated levels of faecal calprotectin (> 59 μg/g), increased levels of C-reactive protein (> 5 mg/L), or a Mayo Endoscopic Score of 2 or 3.
• Patients received 300 mg of intravenous vedolizumab at baseline and weeks 2, 6, and 14; faecal vedolizumab levels were measured on days 1, 4, and 7 and at weeks 2, 6, and 14.
• Clinical disease activity was measured using the SCCAI, with clinical remission defined as a score ≤ 2 and response as a score ≤ 5 with a drop of ≥ 2 points.
• Endoscopic activity was assessed using the UC Endoscopic Index of Severity, with remission defined as a score of 0 or 1 and response as a drop of > 2 points.

TAKEAWAY:

• Vedolizumab was detected in faecal samples of 78% of patients. At week 14, the median SCCAI score declined from 5 at baseline to 1, with clinical response and remission rates of 72% and 61%, respectively. Endoscopic disease activity was alleviated, and quality of life improved.
• At week 14, clinical non-responders had significantly higher levels of faecal vedolizumab than responders (P = .0042), with greater faecal loss (P < .0001).
• When stratified by disease extent, the cumulative rate of faecal drug loss was higher in patients with extensive disease.
• Baseline endoscopic activity was the strongest predictor of vedolizumab faecal loss on days 4 and 7 and at week 2 (P < .05 for all); five serious adverse events were reported in four patients, none attributed to vedolizumab.

IN PRACTICE:

"[The data presented in the study] would appear to support a hypothesis that patients with more severely active disease are prone to lose vedolizumab into their stool, which may impair their likelihood of achieving a good response, possibly through a reduction in circulating serum drug levels," the authors of the study wrote.

SOURCE:

This study was led by Mark A. Samaan, Department of Gastroenterology, Guy's & St Thomas' NHS Foundation Trust in London, England. It was published online on September 02, 2025, in the Journal of Crohn's and Colitis.

LIMITATIONS:

Proteolytic degradation and the delayed use of protease inhibitors may have affected stool measurements of vedolizumab. The cohort size was modest, and data on long-term outcomes and drug-clearance estimates were lacking.

DISCLOSURES:

This study was supported by an Investigator Initiated Research grant from Takeda UK Ltd. Two authors reported receiving lecture and advisory fees from various pharmaceutical companies, of whom one also reported receiving research grants.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.