Treatment of Mycobacterium Avium Complex (MAC) with Azithromycin and Rifampin

Treatment Regimens and Duration

For MAC pulmonary disease, treatment with azithromycin and rifampin (plus ethambutol) should be continued until sputum cultures are negative for 12 months while on therapy, as recommended by the American Thoracic Society 1, 2
The primary microbiologic goal is 12 months of negative sputum cultures while on therapy, with monthly sputum cultures obtained to monitor treatment response 1, 2
Treatment should continue until sputum cultures remain negative for 12 consecutive months, with patients showing clinical improvement within 3-6 months of starting therapy 1, 2, 3

Three-times-weekly regimens are generally better tolerated than daily regimens, with fewer adverse events leading to medication discontinuation, according to the Infectious Diseases Society of America 4, 5, 6
Intermittent (three-times-weekly) therapy is not recommended for patients with cavitary disease, those who have been previously treated, or those with moderate or severe disease 1, 2, 3, 6

Never use macrolide monotherapy due to risk of developing macrolide resistance, as advised by the American Thoracic Society 2
A macrolide with only ethambutol (two-drug regimen) may be adequate for nodular/bronchiectatic disease but should not be used for fibrocavitary disease due to risk of macrolide resistance 2
For disseminated MAC disease, treatment should continue indefinitely unless immune function is restored, according to the Centers for Disease Control and Prevention 1, 7