Test Code VEDOZ Vedolizumab Quantitation with Antibodies, Serum
Ordering Guidance
If there is a known justification for performing both quantitation and antibody levels, this is the correct test to order. If there is not a known reason to perform the antibodies component, consider VEDOL / Vedolizumab Quantitation with Reflex to Antibodies, Serum. VEDOL testing begins with vedolizumab quantitation. When the quantitation results are 15.0 mcg/mL or less, testing for antibodies to vedolizumab will be performed.
Specimen Required
Patient Preparation: For 12 hours before specimen collection, patient should not take multivitamins or dietary supplements (eg, hair, skin, and nail supplements) containing biotin (vitamin B7).
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 1.5 mL Serum
Collection Instructions:
1. Draw blood immediately before next scheduled dose (trough specimen).
2. Within 2 hours of collection, centrifuge and aliquot serum into a plastic vial.
Useful For
Evaluation of patients with loss of response to vedolizumab (VDZ) with recurrence of symptoms and/or low or undetectable serum VDZ measured at trough
Monitoring vedolizumab concentrations in patients undergoing therapy with this biologic for ulcerative colitis or Crohn disease
Assessing the loss of response to VDZ therapy
As an aid to achieving desired serum concentration of VDZ
Profile Information
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| VEDOL | Vedolizumab QN, S | Yes | Yes |
| VEMAB | Vedolizumab Ab, S | No | Yes |
Testing Algorithm
When this test is ordered, vedolizumab quantitation and testing for antibodies to vedolizumab will always be performed.
This test includes both quantitation and antibody testing on all specimens. The therapeutic thresholds for vedolizumab and optimal concentrations associated with good outcomes are not well established. Currently, the American Gastroenterology Association does not have a formal guideline on optimal thresholds for vedolizumab trough concentrations in the setting of loss of response to therapy, but trough concentrations greater than 15 mcg/mL have been associated with clinical or endoscopic remission and mucosal healing in inflammatory bowel disease.
For more information see Ulcerative Colitis and Crohn Disease Therapeutic Drug Monitoring Algorithm.
Reporting Name
Vedolizumab QN with Antibodies, SSpecimen Type
SerumSpecimen Minimum Volume
Serum: 0.3 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Serum | Refrigerated (preferred) | 28 days |
| Frozen | 28 days |
Reject Due To
| Gross hemolysis | OK |
| Gross lipemia | OK |
| Gross icterus | OK |
Reference Values
VEDOLIZUMAB QUANTITATION:
Vedolizumab lower limit of quantitation=1.0 mcg/mL
VEDOLIZUMAB ANTIBODIES:
Antibodies to vedolizumab: <9.8 ng/mL
Absence of antibodies to vedolizumab is defined as <9.8 ng/mL
Presence of ATV is reported as positive when concentrations are ≥9.8 ng/mL
Day(s) Performed
Vedolizumab quantitation: Monday, Wednesday, Thursday
Vedolizumab antibodies: Tuesday, Friday
Report Available
5 to 8 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
80280
82397
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| VEDOZ | Vedolizumab QN with Antibodies, S | 90794-9 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 602807 | Vedolizumab QN, S | 90805-3 |
| 603298 | Vedolizumab Ab, S | 86899-2 |
| 603299 | VEMAB Interpretation | 59462-2 |
Forms
If not ordering electronically, complete, print, and send 1 of the following with the specimen:
-Gastroenterology and Hepatology Test Request (T728)
-Therapeutics Test Request (T831)