Clofazimine in the Treatment of Pulmonary Mycobacterium Avium Complex (MAC)

Inclusion Criteria: * At least 2 positive MAC sputum cultures in the last 12 months with at least one obtained within 12 weeks prior to randomization * Meet ATS/IDSA 2007 pulmonary disease criteria * Adult males and females age 18 or over * Ability to provide informed consent for the use of study drug Exclusion Criteria: * Any patient who is unwilling or unable to provide consent or to comply with this protocol * Cavitary NTM disease * Patients who are currently taking or within the prior 12 weeks received any of the following: bedaquiline, or any component of ATS/IDSA multi-drug recommended therapy (macrolide, ethambutol, rifampin) for MAC * Current usage of inhaled amikacin, tobramycin, or gentamicin * In the judgment of the investigator, the patient is not a candidate for observation (e.g. severe symptoms, extensive disease burden) but rather should be treated with standard multi-drug therapy * Prior use of clofazimine that has resulted in an allergy to clofazimine or a severe adverse reaction * Current usage of medications associated with QT prolongation (see Appendix C for full list of prohibited concomitant medications) * Corrected QT (QTc) interval on electrocardiogram (ECG) \> 470 ms for females or 450 ms for males, calculated using Fridericia's formula60,61 * Advanced lung disease (FEV\<30%) * HIV * Active pulmonary tuberculosis requiring treatment at screening * Active pulmonary malignancy or chemotherapy or radiation within 1 year of screening * Use of chronic s…