Resumption/efficacy and safety of an azithromycin-containing regimen against Mycobacterium avium complex lung disease in patients who experienced adverse effects with a clarithromycin-containing regimen

Antibiotic therapy, including clarithromycin (CLR), has been widely used for the management of Mycobacterium avium complex (MAC) lung disease in clinical settings. When patients develop adverse events (AEs) during CLR-based treatment, the treatment regimen is modified or chemotherapy itself is discontinued. The need for alternative macrolide treatment strategies is emphasized due to the high rate of AEs possibly caused by CLR. Thus, the current study aimed to examine the efficacy and safety of azithromycin (AZM) in patients with MAC lung disease whose treatment was switched from CLR to AZM. We performed a retrospective study of patients with MAC lung disease. The inclusion criteria were as follows: (1) patients who experienced AEs during treatment with antibiotics, including CLR, between December 2012 and November 2017, and (2) those who had antimicrobial therapy that was switched from CLR to AZM. The efficacy and safety of AZM during the clinical course of the disease after switching the regimen from CLR to AZM were investigated. Antibiotic therapy was switched in 31 patients who presented with AEs including drug-induced fever, rash, dysgeusia, liver dysfunction, and neutropenia during treatment with CLR-containing regimens. After switching to AZM, the median duration of treatment was 1286 (364–4615) days. During follow-up, 13 patients had a negative conversion of sputum culture. AZM may be safe and effective for patients with MAC lung disease who have difficulty tolerating CLR. In patients who experienced AEs possibly caused by CLR, switching from CLR to AZM might be an appropriate strategy.