Validation Study of RA-INF-Dx, a Multigene Molecular Test Used to Predict Non-Response to INfliximab Therapy

The RA-INF-Dx test is a non invasive in vitro blood test intended to aid in the identification of patients with RA who are unlikely to show an initial response to infliximab and methotrexate combination therapy. The RA-INF-Dx test is indicated for use in patients: * 18 years of age or older, * Eligible for a first line biologic therapy with infliximab. The RA-INF-Dx test is indicated for use by rheumatologists as a biological basis for guiding infliximab treatment prior to its initiation.