- Treatment with any of the following agents within 28 days of Screening: radiation therapy; cytotoxic chemotherapeutic agents; tuberculosis therapy with the exception of isoniazid (isonicotinylhydrazid, INH); anti-coagulation agents. Immunomodulators that alter immune responses (such as systemic corticosteroids, interleukins, or interferons. Note: Participants using short-term (<1 day) steroid tapers, topical, inhaled and intranasal corticosteroids are eligible for enrollment.