Adalimumab Level for Rheumatic Diseases

Test Code

36299

CPT Codes
80145<br><strong>This test is not available for New York patient testing</strong>

Preferred Specimen

1 mL serum collected in a red-top tube (no gel)

Patient Preparation
Patients should refrain from taking biotin supplements or biotin containing vitamins 24-48 hours before blood draw (applies only when drug level assay is performed together with anti-drug antibody assay).

Minimum Volume

0.5 mL

Instructions

The blood should be drawn just before the next infusion of adalimumab to measure the trough drug level.

Transport Temperature

Refrigerated (cold packs)

Specimen Stability

Room temperature: 48 hours
Refrigerated: 7 days
Frozen -20°C: 14 days
Frozen -70°C: 60 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Serum Separator Tube (SST) • Gross hemolysis

Methodology
Enzyme Linked Immunosorbent Assay (ELISA)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Mon, Tues, Thurs-Sat; Report available: 2-3 days

Reference Range

See Laboratory Report

Clinical Significance

Several studies suggest a target adalimumab trough concentration of 5-12 mcg/mL. Sub-therapeutic adalimumab levels may be due to a patient not yet achieving a steady state trough level early in therapy, inadequate dosing, a dosing interval that is too long or accelerated adalimumab clearance. Accelerated adalimumab clearance may be explained by the presence of adalimumab anti-drug antibody or rheumatoid factor in the patient's serum, or may be caused by other diseases that indirectly lead to immunoglobulin loss (i.e. kidney disease, protein-losing gastroenteropathy). If the steady state trough Adalimumab level is low despite adequate dosing, adalimumab anti-drug antibody testing should be considered.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.