5. Inadequate response to Methotrexate (MTX) treatment defined as oral or parenteral treatment ≥ 3 months with an unchanged mode of application and stable prescribed MTX dose for at least 4 weeks prior to baseline of ≥ 10mg/week and < the upper limit of the applicable approved local label. Subject can also be on stable doses of sulfasalazine and/or hydroxychloroquine, so long as they are also on methotrexate.