Rituximab and Anti-Rituximab Antibody, DoseASSURE™ RTX

CPT: 80299; 82397
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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 Food and Drug Administration.

High serum biotin concentrations in patients taking biotin supplements may cause an interference in this assay. Patients may be advised to stop biotin consumption at least 72 hours prior to sample collection.


Electrochemiluminescence immunoassay (ECLIA); chemiluminescence immunoassay (CLIA)


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
504355 Rituximab Drug + Antibody 504356 Rituximab Drug Concentration ug/mL 82467-2
504355 Rituximab Drug + Antibody 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 504108 Serial Monitoring 000000 Serial Monitoring N/A
Reflex Table for Anti-Rituximab Antibody Level
Order Code Order Name Result Code Result Name UofM Result LOINC
Reflex 1 504108 Serial Monitoring 511958 PDF 80563-0

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