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Rituximab and Anti-Rituximab Antibody, DoseASSURE™ RTX

CPT: 80299; 82397
Updated on 01/29/2020
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  • Anti-CD20
  • Biologics
  • Biopharmaceutical
  • DoseASSURE
  • Rituxan®

Special Instructions

This test includes Serial Monitoring.

Expected Turnaround Time

12 - 16 days

Specimen Requirements




3 mL

Minimum Volume

1 mL (Note: This volume does not allow for repeat testing.)


Gel-barrier tube, red-top tube, or serum transfer tube


Serum must be separated from cells within 45 minutes of venipuncture. Submit serum in a plastic transport tube. To avoid delays in turnaround time when requesting multiple test on frozen samples, please submit separate frozen specimens for each test requested.

Storage Instructions

Refrigerate or freeze

Stability Requirements



Room temperature

7 days


14 days


14 days

Freeze/thaw cycles

Stable x6

Causes for Rejection

Gross hemolysis; gross lipemia; icteric specimen

Test Details


Therapeutic monitoring of rituximab and antidrug antibody development for individuals with non-Hodgkin's lymphoma (NHL), chronic lymphocytic leukemia (CLL), and rheumatoid arthritis. This test provides rituximab drug concentration as well as the level of anti-rituximab antibodies.


Failure of rituximab therapy may not always be due to the presence of anti-rituximab antibodies. Conversely, the absence of anti-rituximab antibodies does not guarantee positive response to treatment.

This test was developed, and its performance characteristics determined, by LabCorp. It has not been cleared or approved by the US Food and Drug Administration (FDA).


Electrochemiluminescence immunoassay (ECLIA); chemiluminescence immunoassay (CLIA)


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
504355 RTA Conc+RTA Ab 504356 Rituximab Drug Concentration ug/mL 82467-2
504355 RTA Conc+RTA Ab 504357 Anti-Rituximab Antibody Level ng/mL 82466-4
Reflex Table for Anti-Rituximab Antibody Level
Order Code Order Name Result Code Result Name UofM Result LOINC
Reflex 1 000000 Serial Monitoring 000000 Serial Monitoring N/A

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