Long-term Follow-up of Mycobacterium avium Complex Lung Disease in Patients Treated With Regimens Including Clofazimine and/or Rifampin

Background Mycobacterium avium complex (MAC) lung disease requires prolonged treatment with multiple antibiotics. Drug intolerances and interactions are common with the current recommended treatment. There is limited information on outcomes with alternative medications. Methods Retrospective review including adult patients with MAC lung disease who were treated and monitored for at least 6 months posttreatment. The aim was to evaluate the clinical and microbiologic outcomes in patients treated with regimens including clofazimine and/or rifampin. Results One hundred and seven patients were included (79% were female; mean age, 67 years). Sputum samples were smear positive in 54% of patients. The majority (84%) were treated with clofazimine in combination with a macrolide and ethambutol. Fourteen patients (13%) were treated with rifampin, macrolide, and ethambutol. Most patients (95%) converted from positive to negative sputum culture results in an average of 4.5 ± 4.2 months (range, 0-30 months). A significantly greater proportion of patients treated with clofazimine converted to negative culture results compared with those treated with rifampin (100% vs 71%; P  = .0002). Microbiologic relapse occurred in 52 of 107 patients (49%). Thirty-six percent of patients required retreatment. There was no difference in microbiologic relapse or re-treatment rates between the two treatment groups. Conclusions The majority of patients with MAC lung disease achieve negative sputum culture results. Re-treatment is needed in approximately one-third of patients. In this cohort, both initial outcomes and re-treatment rates were at least as good in patients treated with clofazimine-containing regimens as in patients receiving rifampin-containing regimens. Clofazimine should be considered as an alternative drug for the treatment of MAC lung disease.