PSHP 2026 Residency Conference

Purpose:
This study evaluates the impact of reduced-dose amikacin liposome inhalation suspension (ALIS) on treatment outcomes in patients with pulmonary nontuberculous mycobacteria (NTM) infections who may experience treatment intolerance. 


Methods:
This was a retrospective, descriptive study. Eligible patients started ALIS therapy from September 1, 2018-June 30, 2024, and filled ALIS through the health system specialty pharmacy. Patients must have completed at least 6 months of ALIS therapy by June 30, 2025. Data was sourced through the pharmacy software system, and data collection was conducted through chart review. Patient adherence was quantified by a percentage of days covered (PDC), calculated based on refill history. The primary outcome was prevalence of negative cultures with various dosing strategies. Secondary outcomes included the incidence of culture reconversion up to one year after the first negative culture conversion or at the end of the study period, new culture resistance, number of patients with reduced ALIS dosing strategies, reasons for ALIS dose adjustments, and total duration of ALIS treatment.  Descriptive statistics were used to report outcomes. 


Results:
30 patients were included in this study and 17 (56%) were considered adherent to daily dosing based on a PDC of >80%. Overall, 24 (80%) patients achieved culture conversion, with 12 of 17 patients in the >80% PDC group and 12 of 13 in the <80% PDC group. Median time to culture conversion was 178.5 (117-216.5) days. Median time to culture conversion in the >80% PDC group was 201 (105-247.25) days vs.146 (122.5-210.75) days in the <80% PDC group. There were 12 (20%) patients with culture reconversion, with 6 of 17 patients in the >80% PDC group and 6 of 13 in the <80% PDC group. One patient (3.3%) developed new resistance to amikacin. There were several reasons for dose adjustment, with the most frequent reason being adverse effects. 


Conclusion:
Dose adjustments of ALIS did not appear to influence the rate of culture conversion in this study. There was a limited impact on resistance or duration of ALIS treatment. This suggests dose adjustment strategies may be an option for patients with adverse effects; however, further research is needed.