Blood Sciences Test

Vedolizumab Drug and Vedolizumab Free Antibody Levels

Vedolizumab Drug and Vedolizumab Free Antibody Levels



Please detail whether vedolizumab drug levels and/or Free anti-vedolizumab antibodies are required on the request form.

The costs are as follows:

Vedolizumab drug levels:                          £29.50

Free anti-vedolizumab antibodies*             £29.50

*Please note, this is a drug sensitive assay, meaning that vedolizumab free antibodies are unlikely to be detected in the presence of vedolizumab.


Vedolizumab drug levels                    mg/L

Vedolizumab free Antibody levels   AU/mL

Test Usage

Vedolizumab is a monoclonal antibody therapy, directed against integrin α₄β₇.  Therapeutic drug monitoring for vedolizumab is not established in clinical practice, but may prove to be useful for managing patients in the settings of treatment failure.

It may be useful to measure trough concentrations of vedolizumab in patients prescribed this drug at the following time points of treatment:

or in the clinical setting of treatment failure.

Please note, samples must be collected at trough i.e. before the next dose.

We have demonstrated that vedolizumab is stable in uncentrifuged clotted blood samples for 7 days at room temperature. Please ensure that samples reach us within 7 days of being taken.

Please note, as the clinical significance of vedolizumab trough concentration is currently not well established, we are unable to provide interpretative comments with vedolizumab results.

If you would like to discuss this further please email the Duty Biochemist


Please note these tests are not UKAS accredited


Specimen Labelling Procedure