Inclusion Criteria:

• Documented history of refractory asthma, as defined by the American Thoracic Society,31 defined as 1 major and at least 2 minor criteria
• Actual or documented history of reversible airway obstruction
• Baseline FEV1 of 40% − 80% of the predicted for height, age, and sex at Screening, as demonstrated 6 or more hours after a short-acting -agonist and/or 24 or more hours after a long-acting -agonist
• History of at least 1 asthma exacerbation leading to oral, IV or IM corticosteroid or ER/Urgent Care Center visit or hospitalization within the past year prior to Screening. This asthma exacerbation should not have been within 30 days prior to Screening
• Adequate cardiac, renal and hepatic function as determined by the principal investigator and demonstrated by Screening laboratory evaluations, questionnaires, and physical examination results that are within normal limits
• Subjects must be able to self-inject study medication or have a designee or healthcare professional who can inject the study medication

Exclusion Criteria:

• Active lung diseases (e.g., bronchitis, chronic obstructive pulmonary disease [COPD], interstitial lung disease, pulmonary fibrosis) other than asthma
• Current treatment for corticosteroid-resistant asthma (e.g., methotrexate [MTX], cyclosporine, gold salts, troleandomycin, immune globulin intravenous [IGIV], mycophenolate mofetil)
• 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 listeria, human immunodeficiency virus (HIV), chronic or active Hepatitis B, an immunodeficiency syndrome, central nervous system (CNS) demyelinating disease or active TB
• Females who are pregnant or will not discontinue breast-feeding.
• Subject with a history of clinically significant drug or alcohol abuse in the last year
• Subjects with a poorly controlled medical condition.
• Abnormal, clinically significant screening laboratory and other analyses (including ECG).
• Subjects with any prior exposure to Tysabri® (natalizumab)
• Prior treatment with any TNF antagonist, including adalimumab