Quantitative determination of free human antibodies against ustekinumab
(e. g. Stelara@)
Ustekinumab is a monoclonal (IgG1), human therapeutic antibody directed against the common subunit (p40) of interleukins 12 and 23 (IL-12/23). These two cytokines play an important role in inflammatory reactions caused by the immune system, such as psoriasis, psoriatric arthritis or Crohn's disease.
Ustekinumab blocks the signalling effect of IL-12/23, thus inhibiting the T-cell-based immune response and has an immunosuppressive and anti-inflammatory effect.
The efficacy of ustekinumab therapy usually correlates with the amount of therapy antibodies that can be detected in the patient's serum shortly before the next dose, the so-called trough level. Various factors influence the level of the trough level: the dose, the frequency of anti-IL12/23 treatment, the disease activity, individual differences in pharmacokinetics and a possible immune response of the patient against the therapy antibody.
During therapy, the patient's immune system may become sensitised to the therapy antibody, leading to the formation of antibodies against the corresponding active substance. These so-called Anti-Drug-Antibodies (ADA) bind to the corresponding active substance and thus lead to a reduction of the concentration (functionally neutralised or excreted faster) and a deterioration of the therapy success.
In addition, the presence of ADA is associated with allergic reactions and a loss of efficacy of the drugs. In the case of primary or secondary therapy failure, the determination of ADA can provide valuable information for optimizing therapy control in addition to drug concentrations. In patients with low drug levels, for example, the decision between changing the therapy regimen and increasing the dose can be made dependent on the presence of ADA.
IDKmonitor® Ustekinumab free ADA ELISA reliably determines the free ADA against Ustekinumab (e.g. Stelara®). No cross-reactivities against anti-Adalimumab, anti-Infliximab, anti-Etanercept, anti-Golimumab and anti-Vedolizumab were detected. Together with the IDKmonitor® Drug Level ELISA for the determination of the drug concentration of Ustekinumab, the IDKmonitor® Ustekinumab free ADA ELISA offers the treating physician the possibility to accompany and optimise the therapy.
The EDTA plasma or serum sample is diluted 1:10 in assay buffer for the test, 2 x 100 µl of this dilution are used for the double determination in the ELISA.
IDKmonitor® Ustekinumab free ADA ELISA K9666