Allergic reactions may occur (anaphylaxis not observed). Rare cases of autoimmune disorder, including lupus-like syndrome or autoimmune hepatitis, reported. Rare reactivation of hepatitis B occurred in chronic carriers of the virus. Serious and potentially fatal infections reported, including bacterial sepsis and tuberculosis. Use may affect defenses against malignancies. Tuberculosis (disseminated or extrapulmonary) reported (reactivation of latent infection and new infections). Use with caution in pre-existing or recent onset CNS demyelinating disorders (rare cases of new onset or exacerbation of CNS demyelinating disorders have occurred). Optic neuritis, transverse myelitis, multiple sclerosis, and new onset or exacerbation of seizures reported. Use with caution in heart failure or decreased left ventricular function (worsening and new-onset heart failure reported). Use with caution in history of significant hematologic abnormalities (associated with pancytopenia and aplastic anemia). Use not recommended in patients with Wegener’s granulomatosis receiving immunosuppressive therapy (higher incidence of noncutaneous solid malignancies). Should not be used in combination with anakinra unless no satisfactory alternatives exist (higher incidence of serious infections). Patients with a significant exposure to varicella virus should temporarily discontinue therapy. Some dosage forms may contain dry natural rubber (latex). Live vaccines should not be given concurrently.