The Impact of Anti-TNF Exposure on Vedolizumab Effectiveness

Patients will be enrolled in the study when they are selected to initiate vedolizumab
therapy. Vedolizumab is an intravenous infusion given at increasing intervals. The first
infusion of vedolizumab will be considered baseline. Patients may be enrolled at baseline or
at colonoscopy prior to the first scheduled infusion of vedolizumab (pre-treatment visit).
The standard induction protocol for vedolizumab consists of infusions at week 0 (baseline),
week 2, and week 6. Vedolizumab, as per standard-of-care, is then continued at an interval
of every 8 weeks following induction therapy. Vedolizumab treatment will be prescribed as
per standard practice and will be prescribed regardless of participation in this study.
Patients will not receive medication for the sole purpose of this research. Treatment
decisions including timing of wash out period between anti-TNf and vedolizumab will be made
by the subject's physician and not per the research protocol. There will not be a
protocolized washout period for patients previously receiving anti-TNF therapy because
treatment will be standard of care and per the directing physician.

Standard of care laboratory tests will be performed by the clinical laboratory at Mount
Sinai Hospital. All other measurements will be completed at Prometheus Therapeutics &
Diagnostics in San Diego, California or at a Takeda identified lab for vedolizumab
concentrations and antibodies.

Inclusion Criteria:

- Male and female adults with a diagnosis of inflammatory bowel disease

- Patients who will be started on vedolizumab therapy as clinically indicated and in
discussion with their treating physician will be eligible. Patients will not be
started on vedolizumab for the sole purpose of this study

Exclusion Criteria:

-Patients with prior exposure to vedolizumab or natalizumab