Association Between the Need to Change Initial Antifungal Therapy and Treatment Costs in Patients With Invasive Aspergillosis

Background: Early antifungal initiation in invasive aspergillosis (IA) is recommended. Changing antifungals occurs for a myriad of reasons but associated costs are unclear.

Methods: US claims data for adults admitted for IA were identified from 10/1/2015 to 11/30/2022. Patients were stratified by those who did and did not change antifungal therapy. Adjusted all-cause healthcare utilization and costs/patient during index hospitalization and at 1, 6, and 12-months after the index date between the cohorts that did and did not change antifungal therapy were compared.

Results: Among 1,192 IA patients, 707 (59.3%) changed their initial antifungal therapy over follow-up. The index hospital length of stay was longer (Δ = 6 days, P < .001) and costs were higher (Δ = $65,149, P < .001) in the change vs. no change cohort. Median 1, 6, and 12-months all-cause costs were higher in patients changing antifungal therapy vs. not (Δ = $90,938-$192,953).

Conclusions: Changing antifungals was associated with longer hospital stays and costs and higher all-cause costs over 12-months.