A Study of the Safety, Tolerability and Efficacy of Treatment With AP1189 in Early RA Patients With Active Joint Disease

Inclusion Criteria: * Written informed consent has been obtained prior to initiating any study specific procedures * Male and female subjects, 18 to 85 years of age * Confirmed diagnosis of RA (Rheumatoid Arthritis) according to the 2010 American College of Rheumatology (ACR)/EULAR RA classification criteria * Polyarthritis with joint swelling and tenderness of a minimum of three joints out of 68 joints tested * Candidate for Methotrexate treatment * Is about to begin treatment with MTX (Methotrexate) * Tested positive for anti-CCP (Anti-cyclic citrullinated peptide) or RF (Rheumatoid Factor) * Severe active RA (Clinical Disease Activity Index (CDAI)) \> 22) at screening and baseline * Negative QFG-IT (QuantiFERON-in-Tube test) * Subjects should be able to complete the PRO (Patient Reported Outcome) questionnaires * Females of child-bearing potential may only participate if using reliable means of contraception or are post-menopausal. Surgically sterilized women at least 6 months prior to screening * Females of childbearing potential must have a negative pregnancy test at screening and baseline Exclusion Criteria: * Participation in any other study involving investigational drug(s) within 4 weeks prior to study entry * Major surgery within 8 weeks prior to screening or planned surgery within 1 month following randomization * Rheumatic autoimmune disease other than RA, including SLE (systemic Lupus Erythematosus), MCTD (Mixed Connective Tissue Disease), scleroderma, polymyositis, or significant systemic involvement secondary to RA. Sjögren syndrome with RA is allowable * Functional class IV as defined by the ACR Criteria for Classification of Functional Status in RA or wheelchair/bedbound * Prior history of or current inflammatory joint disease other than RA * Subjects with fibromyalgia * Initiation or change in dose for NSAIDs within 2 weeks prior to dosing with the IMP (Investigational Medicinal Product) * Corticosteroids are prohibited within 2 weeks prior to screening (and during the entire treatment period and until the final visit * Evidence of serious uncontrolled concomitant cardiovascular, nervous system, pulmonary, renal, hepatic, endocrine, or gastrointestinal disease * Have prior renal transplant, current renal dialysis or severe renal insufficiency (determined by a derived glomerular filtration rate (GFR) using Cockcroft Gault Formula of ≤30 mL/min/1,73 m2 calculated by the local lab) * Uncontrolled disease states, such as asthma, psoriasis, or inflammatory bowel disease where flares are commonly treated with oral or parenteral corticosteroids * Evidence of active malignant disease * Pregnant women or nursing mothers * History of alcohol, drug, or chemical abuse within the 6 months prior to screening * Neuropathies or other painful conditions that might interfere with pain evaluation * Body weight of \>150 kg Exclusion criteria that only applies for Norway * Evidence of moderate and/or severe organ dysfunction * Abnormal chest x-ray (as per the discretion of the investigator * Evidence of positive hepatitis serology * Evidence of peptic ulcer disease