Study to Determine the Effects of Different Doses of Methotrexate (MTX) When Taken With Adalimumab in Subjects With Early Rheumatoid Arthritis (RA)

* Male and female subjects at least 18 years of age * Subject has a diagnosis of Rheumatoid Arthritis (RA) as defined by either the 1987-revised American College of Rheumatology (ACR) classification criteria or the new ACR/ European League Against Rheumatism (EULAR) diagnostic criteria for RA 2010 and has a disease duration of less than 1 year from diagnosis by a licensed health care provider * Subject must meet the following criteria: 1. Disease Activity Score of C-reactive Protein (DAS28\[CRP\]) ≥ 3.2 (at the Baseline visit only) 2. At least 6 swollen joints out of 66 assessed (at the Screening and Baseline visits) 3. At least 8 tender joints out of 68 assessed (at the Screening and Baseline visits) 4. C-reactive protein (CRP) ≥ 1.5 mg/dL (at the Screening visit only), or erythrocyte sedimentation rate (ESR) ≥ 28 mm/1h (at the Screening and Baseline visits) 5. Fulfill at least one of the following three criteria: Rheumatoid Factor (RF) positive, have at least 1 bony erosion, anti-cyclic citrullinated peptide (anti-CCP) antibody positive * Subject is judged to be in good health as determined by the Principal Investigator based upon the results of medical history, laboratory profile, physical examination, chest x-ray (CXR), and a 12-lead electrocardiogram (ECG) performed during Screening

* Subject has previous exposure to any systemic biologic therapy including adalimumab * Subject has been previously treated with greater than 1 disease modifying antirheumatic drugs (DMARDs) or with methotrexate (MTX) * Subject has undergone joint surgery within the preceding two months (at joints to be assessed within the study) * Subject has chronic arthritis diagnosed before age 17 years * History of invasive infection (e.g., listeriosis and histoplasmosis), chronic or active Hepatitis C infection, human immunodeficiency virus (HIV) infection, immunodeficiency syndrome, chronic recurring infections or active tuberculosis (TB) * Hepatitis B virus: hepatitis B surface antigen (HBs Ag) positive (+) or detected sensitivity on the hepatitis B virus DNA (HBV DNA) polymerase chain reaction (PCR) qualitative test * Infection(s) requiring treatment with intravenous (IV) anti-infectives within 30 days prior to the Baseline Visit or oral anti-infectives within 14 days prior to the Baseline visit * Female subject who is pregnant or breast-feeding or considering becoming pregnant