Blood Sciences Test


Vedolizumab Drug Levels



Special instructions

Please note- this test is currently provided as part of a service evaluation-  details of which can be found here.

All requests for vedolizumab must be accompanied by a completed service evaluation form: Vedolizumab form for clinical data collection_171220. Requests received without this information will not be analysed.


Please note our vedolizumab service evaluation is coming to an end on July 31st 2019.  Any samples received in Exeter on or after 1st August 2019 will not form part of the service evaluation, and the bespoke clinical information form will not be required. Please detail whether vedolizumab drug levels or Free anti-vedolizumab antibodies are required on the request form. The costs from 1st August are as follows:

Vedolizumab drug levels:                          £29.50

Free anti-vedolizumab antibodies             £29.50



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.

For a limited time only, we are undertaking a service evaluation to determine if vedolizumab drug level is correlated with disease activity score, and therefore determine if measuring vedolizumab levels is a useful clinical tool We are offering a subsidised service (£15 per sample) for analysis of vedolizumab drug levels, and require clinical information to allow us to collate drug levels with clinical response.

If you would like to take part in the vedolizumab service evaluation, please send samples (serum or clotted whole blood, room temperature postage) with a request form in addition to the Vedolizumab Clinical Information Form to Blood Sciences, ensuring that packaging complies with UN3373 requirements.

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 for this service evaluation.

Please note, vedolizumab antibody assay is currently unavailable.

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


Please note this test is not UKAS accredited


Specimen Labelling Procedure