Abstract Background Amikacin liposome inhalation suspension (ALIS) has been used in several countries including Japan for refractory Mycobacterium avium complex pulmonary disease (MAC-PD). Although its efficacy and adverse events have been reported, factors that limit optimal treatment outcomes in real-world practice are not fully understood. Therefore, we aimed to provide practical considerations for optimizing ALIS therapy by identifying factors associated with culture conversion. Methods We retrospectively reviewed the medical records of patients with refractory MAC-PD who were treated with ALIS at a single center between October 2021 and June 2025. Patients treated for ≥ 6 months were included and categorized into culture conversion and non-conversion groups. Clinical characteristics and treatment-related factors were analyzed. Follow-up continued until December 2025. Results During the study period, 30 patients with refractory MAC-PD were treated with ALIS. Three patients who discontinued ALIS within 6 months were excluded from further analysis because of MAC-related death ( n = 1) or severe ALIS-related adverse events ( n = 2). Consequently, 27 patients were included in the analysis. The median age was 69.9 years, and the median duration of ALIS therapy was 14.6 months. The sputum culture conversion rate was 51.8% (14/27; 95% CI, 34.0-69.3%). Pulmonary fungal disease was identified in 7 patients (25.9%), including newly diagnosed cases during ALIS therapy; however, pulmonary fungal disease was not significantly associated with culture conversion. Cavitary lesions and prior aminoglycoside use were significantly associated with non-conversion. In addition, inappropriate ALIS administration, including prolonged intermittent use and inadequate nebulizer handset replacement, was significantly associated with non-conversion. Dysphonia was the most frequent adverse event and occasionally led to prolonged intermittent use of ALIS. ALIS-related lung abnormalities on computed tomography (CT) scans were observed in 21 of 26 patients. Conclusions Cavitary lesions, prior aminoglycoside use, and inappropriate ALIS administration were associated with culture non-conversion. Several factors related to ALIS administration and inhalation management may be modifiable, and appropriate patient education, regular reassessment of inhalation practices, and careful monitoring of ALIS administration may help optimize treatment outcomes.
Kurosaki et al. (Wed,) studied this question.