Inclusion Criteria:

• Subject must have successfully enrolled in and completed Protocol M06-806 through Week 52.
• Subject must be a responder at Week 52 of Study M06-806.

• If female, subjects who are sexually active and are of child-bearing potential should be practicing an approved method of birth control throughout the study and for 150 days after study drug administration. Examples of approved methods of birth control include the following:

  • Condoms, sponge, foam, jellies, diaphragm or intrauterine device (IUD)
  • Oral, parenteral or intravaginal contraceptives
  • A vasectomized partner
• Subject of legal age, parent or legal guardian, as required, has voluntarily signed and dated an Institutional Review Board (IRB)/Independent Ethics Committee (IEC) approved informed consent form, after the nature of the study has been explained and the subject of legal age, subject's parent, or legal guardian, as required, has had the opportunity to ask questions. Subjects will be included in all discussions, and if required, their signature on an assent form will be obtained.
• Parent or legal guardian of subject who is not of legal age, as required, 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.
• If a subject of legal age, must be willing to actively store, administer, and accurately record study drug administration in the subject diary.
• Subject is judged to be in acceptable medical condition, as determined by the Principal Investigator based upon results of clinical and laboratory evaluations done throughout the preceding Crohn's disease study M06-806.

Exclusion Criteria:

• For any reason, the subject is considered by the Investigator to be an unsuitable candidate for continuing therapy in the M06-807 study.
• Subject has abnormal laboratory or other test results that in the opinion of the Investigator will make the subject unsuitable to participate in this study.
• History of cancer or lymphoproliferative disease other than a successfully and completely treated cutaneous squamous cell or basal cell carcinoma or carcinoma − in-situ of the cervix.
• History of listeriosis, histoplasmosis, chronic or active hepatitis B infection, human immunodeficiency virus (HIV) infection, any immunodeficiency syndrome, central nervous system (CNS) demyelinating disease or active TB (receiving treatment or not receiving treatment). Ongoing severe infections such as sepsis and opportunistic infections will be exclusionary.
• Subject with known, symptomatic obstructive strictures.
• Subject who is planning surgical bowel resection at any time point while enrolled in the study.
• Subject who has short bowel syndrome as determined by the Investigator.
• Subject who is currently receiving total parenteral nutrition (TPN).
• Subject who is unwilling to discontinue growth hormone prior to the first dose of open-label study drug at the Baseline visit of M06-807.
• Female subject who is pregnant or currently breast-feeding.
• Subject with a history of clinically significant drug or alcohol abuse in the last year.
• Subject with a poorly controlled medical condition such as: uncontrolled diabetes, recurrent infections, unstable ischemic heart disease, moderate to severe heart failure, recent cerebrovascular accidents or any other condition which, in the opinion of the Investigator or the Sponsor, will put the subject at risk by participation in the protocol.
• Subject with any prior exposure to Tysabri (natalizumab).
• Subject with a known hypersensitivity to the excipients of adalimumab as stated in the label.
• Subject with a previous history of dysplasia of the gastrointestinal tract.