1.1 Enzyme-linked immunosorbent assay (ELISA) tests for therapeutic monitoring of tumour necrosis factor (TNF)-alpha inhibitors (drug serum levels and antidrug antibodies) show promise but there is currently insufficient evidence to recommend their routine adoption in rheumatoid arthritis. The ELISA tests covered by this guidance are Promonitor, IDKmonitor, LISA-TRACKER, RIDASCREEN, MabTrack, and tests used by Sanquin Diagnostic Services.
1.2 Laboratories currently using ELISA tests for therapeutic monitoring of TNF-alpha inhibitors in rheumatoid arthritis should do so as part of research and further data collection (see section 5.22).
Why the committee made these recommendations
TNF-alpha inhibitors can be an effective treatment option for severe rheumatoid arthritis that does not respond to conventional therapy. Therapeutic monitoring of TNF‑alpha inhibitors could help to optimise their use, improving management of the condition and outcomes that are important for people with rheumatoid arthritis. These include how long their disease is in remission, the rate of flares and relapse, and health-related quality of life.
The clinical-effectiveness evidence for ELISA tests for therapeutic monitoring of TNF‑alpha inhibitors in rheumatoid arthritis is not robust, although there are some positive trends. The key INGEBIO study is of poor quality and is not generalisable to NHS practice.
Results of the economic modelling based on INGEBIO are uncertain. So, although the tests show some promise, they are not recommended for routine use in the NHS. Further research would be valuable.