|Downtime form:||A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery|
|Red top tube 5 mL (Clot Activator)|
Absolute Minimum: 0.75 mL serum in red top tube
Assessing the response to therapy with vedolizumab
An aid to achieving desired trough serum levels of vedolizumab
Monitoring patient compliance
Patients actively undergoing therapy with both vedolizumab and nivolumab (extremely rare scenario) should not have their therapeutic vedolizumab concentration assessed using this test. If the patient has taken nivolumab in the past, they should wait for 4 weeks after therapy with nivolumab has ended before being tested for vedolizumab quantitation using this method.
The presence of high concentrations of vedolizumab might inhibit the antibodies to vedolizumab (ATV) assay yielding false-negative results. In patients with concentrations of vedolizumab greater than 15.0 mcg/mL, the presence of an ATV is of little clinical significance.
Clinical management decisions for patients receiving vedolizumab treatment should not be based solely on quantitation of vedolizumab and assessment of ATV if appropriate. Test results must be interpreted within the clinical context of the patient.
Testing for antibodies to vedolizumab is accomplished using a laboratory-developed immunoassay.