['arthritis, rheumatoid']
['gsk3196165', 'mtx', 'folic acid', 'placebo']

        Inclusion Criteria:

          -  Age >=18 years at the time of signing informed consent.

          -  Meets ACR/EULAR 2010 RA Classification Criteria, with disease duration of >=12 weeks.

          -  Swollen joint count of >=4 (66-joint count) and tender joint count of >=4 (68-joint
             count).

          -  DAS28(CRP) >=3.2.

          -  CRP >=5.0 milligram per litre (mg/L) at screening.

          -  Must have previously received MTX (15-25 mg weekly) for at least 12 weeks before
             screening, with no change in route of administration, with a stable and tolerated dose
             for >=4 weeks prior to Day 1. A stable dose of MTX >=7.5 mg/week is acceptable, if the
             MTX dose has been reduced for reasons of documented intolerance to MTX, e.g. hepatic
             or hematologic toxicity, or per local requirement.

          -  Weight >=45 kilogram (kg).

          -  Male or female subjects are eligible to participate so long as they meet and agree to
             abide by the contraceptive criteria.

          -  Diffusing capacity of the lung for carbon monoxide (DLCO) >=60% predicted; forced
             expiratory volume in 1 second (FEV1) >=70% predicted

          -  No evidence of active or latent infection with Mycobacterium tuberculosis (TB).

        Exclusion Criteria:

          -  Pregnant or lactating women.

          -  History of other inflammatory rheumatological or autoimmune disorders, other than
             Sjögren's syndrome secondary to RA.

          -  History of any respiratory disease which (in the opinion of the investigator) would
             compromise subject safety or the ability of the subject to complete the study (e.g.
             significant interstitial lung disease, such as pulmonary fibrosis, chronic obstructive
             pulmonary disease (COPD), moderate-severe asthma, bronchiectasis, previous pulmonary
             alveolar proteinosis [PAP]).

          -  Clinically-significant or unstable (in the opinion of the investigator) persistent
             cough or dyspnea that is unexplained.

          -  Significant unstable or uncontrolled acute or chronic disease which, in the opinion of
             the investigator, could confound the results of the study or put the subject at undue
             risk.

          -  A history of malignancy.

          -  Hereditary or acquired immunodeficiency disorder, including immunoglobulin deficiency.

          -  Current/previous Hepatitis B virus (HBV), Hepatitis C virus (HCV) or human
             immunodeficiency virus (HIV) 1 or 2 infection.
      