Test for ADA (anti-drug antibodies) against TNF-alpha- inhibitors

- When suspecting treatment failure with TNF-alpha inhibitors.

When the patient has measurable, but low, concentration of drug in the blood (0.65 - 10 µg /mL) we can offer a test to verify if the patient has developed ADA (anti-drug antibodies).

Method

Acid-EIA
Prior to analysis, serum is treated with acid and diluted to allow dissolution of immune complexes, as shown in the figure below.

The test is an enzyme immuno assay (EIA) for the determination of antibodies binding to TNF-alpha inhibitors in serum. The procedure can be described as a sandwich EIA.

Result/interpretation

The measurement of anti-drug antibodies is qualitative.
ADAs do not cross-react between the different TNF inhibitors.



Interpretation of the result is summarised in algorithms that are found here.
Sampling instructions are found here.