Active Juvenile Idiopathic Arthritis (JIA) Compassionate Use

1. A parent or guardian has voluntarily signed and dated an informed consent form, approved by an Institutional Review Board (IRB)/Independent Ethics Committee (IEC), after the nature of the study has been explained and the subject's parent or legal guardian has had the opportunity to ask questions. The informed consent must be signed before any study-specific procedures are performed or before any medication is discontinued for the purpose of this study. The parent must also be willing to comply with all the requirements of this study protocol. 2. Subject has a disease diagnosis of moderately to severely active polyarticular or polyarticular course juvenile idiopathic arthritis (JIA; defined as arthritis affecting \> = 5 joints at the time of treatment initiation). This corresponds to the International League of Associations for Rheumatology categories of polyarticular rheumatoid factor positive (RF+), polyarticular Rheumatoid factor negative (RF-) disease, and extended oligoarthritis disease. 3. Subject must be aged 2 to \< 4 years old with moderately to severely active polyarticular JIA or polyarticular course JIA or age 4 or greater weighing \< 15 kg with moderately to severely active polyarticular JIA or polyarticular course JIA, per International League of Associations for Rheumatology (ILAR) criteria. 4. Subject is judged to be in generally good health as determined by the Investigator based upon the results of medical history, laboratory profile, and physical examination performed at Screening and confirmed at Baseline. This includes, but is not limited to, a normal cardiopulmonary and normal neurological exam result. 5. Parent or legal guardian must be able and willing to administer subcutaneous (SC) injections or have a qualified person available to administer SC injections. 6. Parent or legal guardian must be willing to actively supervise storage and administration of study drug and to ensure that the time of each dose is accurately recorded in the subject's diary. 7. Subject must have negative purified protein derivative (PPD) test (or equivalent) at Screening. If subject has a positive (greater than or equal to 5mm induration) PPD test result, a chest x-ray (posterior-anterior \[PA\] and lateral view) must be performed. If subject has a positive test (or equivalent), has had a past ulcerative reaction to PPD placement, and/or a chest x ray consistent with tuberculosis \[TB\] exposure, subject may not be enrolled into the study. 8. For subjects in the European Union \[EU\], subject must have previously failed, had an insufficient response, or have been intolerant to at least one Disease-Modifying Anti Rheumatic Drug (DMARD).

1. Subject has had prior exposure to Tysabri® (natalizumab) or Raptiva® (efalizumab) or any other biologic therapy, such as Orencia® (abatacept), Kineret® (anakinra), Actemra® (tocilizumab), Rituxan® (rituximab). Any previous use of anti-tumor necrosis factor \[TNF\] agents, including Enbrel® (etanercept), Remicade® (infliximab), Cimzia® (certolizumab pegol), Simponi® (golimumab), and adalimumab is also prohibited. 2. Infection(s) requiring treatment with intravenous (IV) anti-infectives within 30 days prior to Baseline Visit or oral anti-infectives within 14 days prior to the Baseline Visit. 3. Subject has undergone joint surgery within the preceding two months of the Screening Visit (at joints to be assessed within the study). 4. Subject has a previous diagnosis of a condition that could cause arthritis other than polyarticular JIA. 5. Subject has a history of an allergic reaction or significant sensitivity to constituents of the study drug, adalimumab. 6. Subject has been treated with any investigational drug of chemical or biologic nature within a minimum of 30 days or 5 half lives (whichever is longer) of the drug prior to Baseline visit. Should these biologics become approved, they would continue to be excluded. 7. Subject has a poorly controlled medical condition, such as uncontrolled diabetes, unstable heart disease, recent cerebrovascular accidents, seizure disorder, and any other condition which, in the opinion of the Investigator, would put the subject at risk by participation in the study. 8. Subject has a history of clinically significant hematologic (e.g., severe anemia, leukopenia, thrombocytopenia, a clotting disorder), renal, liver disease (e.g., fibrosis, cirrhosis, hepatitis), or active gastroenteric ulcer. 9. Subject is considered by the Investigator, for any reason, to be an unsuitable candidate for the study. 10. Subject has evidence of active TB infection. 11. Subject has history of moderate to severe congestive heart failure (New York Heart Association \[NYHA\] class III or IV), recent cerebrovascular accident or thrombotic event and any other condition which, in the opinion of the investigator, would put the subject at risk by participation in the protocol. 12. Evidence of dysplasia or history of malignancy (including lymphoma and leukemia). 13. History of demyelinating disease (including myelitis) or neurologic symptoms suggestive of central nervous system \[CNS\] demyelinating disease. 14. History of invasive fungal infection (e.g., listeriosis, histoplasmosis), active viral disorders, human immunodeficiency virus (HIV) infection. 15. Positive Hepatitis B test result. 16. Chronic recurring infections or active TB. 17. Screening laboratory and other analyses show any of the following abnormal results: * electrocardiogram \[ECG\] - with clinically significant abnormalities; * Aspartate transaminases (AST) or alanine transaminase (ALT) \> 1.75 the upper limit of the reference range; * Total bilirubin \>=3 mg/dL; * Serum creatinine \> 1.6 mg/dL (convert to mmol/L). 18. Evidence of dysplasia or history of malignancy (including lymphoma and leukemia) other than a successfully treated non-metastatic cutaneous squamous cell or basal cell carcinoma.