Vedolizumab Quantitation with Reflex to Antibodies, Serum (Sendout)

Useful For:

• Assessing the response to therapy with vedolizumab
• An aid to achieving desired trough serum levels of vedolizumab
• Monitoring patient compliance

Testing Algorithm: When Vedolizumab quantitation results are 15.0 mcg/mL or less, then testing for antibodies to vedolizumab will be performed at an additional charge.

Vedolizumab Quantitation: Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Vedolizumab Antibody: Electrochemiluminescent Bridging Immunoassay

Reference Values:

• Vedolizumab lower limit of quantitation: 2.0 mcg/mL
• Antibodies to Vedolizumab: <9.8 ng/mL

Cautions:

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.

Samples containing more than 100 ng/mL biotin (vitamin B7) may interfere (in the form of depressed signal) with VEMAB / Vedolizumab Antibodies, Serum.

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.

Draw blood immediately before next scheduled dose (trough specimen).

Collect 5 mL in RED TOP tube (preferred)

• Also Accepted: GOLD SST

Centrifuge sample and transfer serum to a separate plastic vial within 2 hours of collection. Refrigerate serum.

Login: SEND1-;REFRIG

• RSNDT1: MAYOSD
• RSTYP1: SRM
• RTRSQ1: ;Vedolizumab Quantitation with Reflex to Antibodies (Mayo Test VEDOL)

Sendouts, order Mayo Test: VEDOL.

Stability: Refrigerated (Preferred): 28 days; Frozen: 28 days; Ambien: Unacceptable.

Reject Due To: Gross lipemia. Gross hemolysis, gross icterus are acceptable.

CPTs:

• Vedol Quant: 80280
• Vedol Ab, if performed: 82397