Safety and Efficacy of Inhaled Interferon Gamma-1b in Pulmonary MAC Infection

The purpose of this research study is to test the safety and effectiveness of inhaled Interferon gamma-1b (IFN-g 1b), when administered for 48 weeks and in combination with oral antibiotics which may be administered for up to 72 weeks for the treatment of a lung infection caused by a bacterium called Mycobacterium avium complex . FDA has not approved Interferon gamma-1b for use in patients with MAC infection of the lungs, which is the purpose of this study.Interferon gamma-1b and similar proteins play important roles in establishing and maintaining protective immune responses against a variety of microorganisms.