Economic impact of managing invasive mold disease with isavuconazole compared with liposomal amphotericin B followed by posaconazole in Spain.

Background: Invasive fungal infections (IFI) are associated with significant morbidity and mortality. The objective of this work was to compare the costs per adult patient, associated with intravenous isavuconazole (ISAV) followed by oral ISAV versus the regimen of liposomal amphotericin B followed by posaconazole (L-AMB→POSA) in the treatment of IFI. The comparison was conducted from the perspective of the Spanish National Health System (SNS).

Methods: As indirect comparisons have demonstrated similar efficacy between the comparators, a cost-minimization approach was taken. Drug acquisition, administration, hospitalization, laboratory tests and adverse events costs were evaluated from SNS perspective. Deterministic and probabilistic sensitivity analyzes were performed.

Results: Total costs per-patient were €24,715.54 with ISAV versus €29,753.53 with L-AMB→POSA, resulting in cost-savings per patient treated with ISAV of €5,037.99 (-16.9%). Treatment costs of IFI remained lower for ISAV than for L-AMB→POSA across all sensitivity analyses (-7,968.89€ to -326.59€), being treatment duration the most influential parameter.

Conclusion: According to the present model, the treatment of IFIs with ISAV would generate savings for the SNS compared to L-AMB→POSA. These savings are attributed to the shorter duration of IV treatment, reduced use of healthcare resources and lower costs associated with managing adverse effects when ISAV was employed.