- Any active or recent history (within 6 months of first study dose) of autoimmune disease or syndrome that requires systemic corticosteroids (>10 mg daily prednisone equivalent) or immunosuppressive medications including but not limited to: myasthenia gravis, myositis, autoimmune hepatitis, systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, vascular thrombosis associated with anti-phospholipid syndrome, Wegner's granulomatosis, Sjogren's syndrome, Guillain-Barre syndrome, multiple sclerosis, vasculitis, or glomerulonephritis. Subjects with vitiligo, controlled type I diabetes mellitus, residual hypothyroidism due to autoimmune thyroiditis only requiring hormone replacement therapy are permitted to enroll.