The purpose of this study is to estimate the effect of anakinra, 100 mg once daily (QD), on the development of an anti-tetanus antibody response in subjects with RA after vaccination with a tetanus and diphtheria toxoids injection. In addition, this study will evaluate the general safety profile of therapy with anakinra, 100 mg QD, in subjects with RA after vaccination with a tetanus and diphtheria toxoids injection.

Ages Eligible for Study:  18 Years   -   74 Years,  Genders Eligible for Study:  Both

Criteria

Inclusion Criteria:

• Diagnosed with RA by American College of Rheumatology (ACR) criteria for greater than or equal to 12 weeks
• Active RA with at least 3 swollen joints and 3 tender/painful joints and at least one of the following: *Morning stiffness greater than or equal to 45 minutes; *C-reactive protein (CRP) greater than or equal to 1.5 mg/dL; *Erythrocyte sedimentation rate greater than or equal to 28 mm/hr; *Stable methotrexate dose of less than or equal to 20 mg/week for 8 weeks prior to randomization; *Stable doses of nonsteroidal anti-inflammatory drugs (NSAIDs) and oral corticosteroids (less than or equal to 10 mg/day of prednisone or equivalent) for 4 weeks prior to randomization.

Exclusion Criteria:

• Pregnant or breast-feeding women
• Any uncontrolled, clinically significant systemic disease
• Has total white cell count less than 3.5 x 10^9/L, a neutrophils count less than 2.0 x 10^9/L, platelet count less than 125 x 10^9/L or hemoglobin (Hgb) less than 8.0 g/dL at screening
• Abnormal liver function tests (AST/ALT greater than or equal to 1.5 x the upper limit of normal at screening)
• Serum creatinine greater than 1.5 x the upper limit of normal at screening
• Subject recall of having tetanus toxoid or diphtheria vaccination less than 10 years prior to randomization
• Has never received a primary tetanus vaccination
• Any other vaccination within 12 weeks of randomization
• Disease-modifying antirheumatic drugs (DMARDs) other than methotrexate
• Biologics to treat RA within the previous 8 weeks of screening (e.g., etanercept, infliximab)
• Subjects were treated with anakinra within 4 weeks prior to randomization