A phase therapy regimen containing clofazimine manifested high efficacy in treating Mycobacterium abscessus pulmonary disease.

BACKGROUND

The guidelines for Mycobacterium abscessus pulmonary disease do not provide a clear approach to combination therapy. This study aims to assess the effectiveness of phase therapy (PT) containing clofazimine (CFZ) for patients with Mycobacterium abscessus pulmonary disease.

METHODS

This study was carried out at Beijing Chest Hospital, Capital Medical University. It included 24 confirmed cases of Mycobacterium abscessus pulmonary disease who were prospectively enrolled and treated with a CFZ-containing regimen. Additionally, 35 confirmed cases were retrospectively included for comparison. Baseline information of patients was collected. Patients were followed up for over a year. Minimal inhibitory concentration (MIC) testing was conducted on clinical isolates from patients to determine if there is a correlation between MIC values and sputum culture conversion.

RESULTS

The retrospective patients achieved a 36.7% (11/30) sputum culture conversion while PT achieved a 70.8% (17/24) sputum culture conversion. Patients using the PT regimen were more likely to achieve sputum culture conversion (P = 0.013). The MIC range of CFZ of baseline isolates from 54 Mycobacterium abscessus pulmonary disease patients was 0.125 -1 mg/L. Among prospective patients, the success rate of treatment was 86.7% (13/15) for patients with CFZ MIC < 0.5 mg/L, while it was 44.4% (4/9) for those with MIC ≥ 0.5 mg/L. Prospective patients with CFZ MIC < 0.5 mg/L were more likely to achieve sputum culture conversion (P = 0.014). Logistic regression analysis showed that prospective patients who received the five-drug regimen were independently associated with sputum culture conversion [OR = 6.203, 95% CI = (1.171–32.865), P = 0.032).

CONCLUSION

The PT regimen is effective against Mycobacterium abscessus pulmonary disease, particularly in cases where CFZ MIC is < 0.5 mg/L.