(198) Real World Experience of Breakthrough Invasive Fungal Infections on Isavuconazole vs. Posaconazole in Malignant Hematology Patients

Poster Abstract:

Background:
Prolonged and profound neutropenia often caused by certain treatments for hematologic malignancies is a significant risk factor for invasive fungal infections (IFIs), which remains a major cause of mortality in this patient population. Primary prophylaxis is the main strategy for preventing IFIs, and current guidelines recommend prophylaxis with posaconazole as the standard of care for IFI prevention in patients with acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) receiving myelosuppressive chemotherapy or in allogeneic stem cell transplant. As an alternative mold-active antifungal, isavuconazole has also been implemented in clinical practice for prophylaxis due to its ease of dosing, limited need for drug level monitoring, and favorable side effect profile. Although prophylaxis with one of these agents has reduced the overall incidence of IFIs, breakthrough invasive fungal infections (bIFIs) have increasingly been described in the literature. However, the incidence of bIFIs varies widely based on antifungal agent used, local epidemiology, and patient characteristics.

Objective(s):
The objective of this study is to describe and compare the incidence of bIFIs in malignant hematology patients receiving either isavuconazole or posaconazole for prophylaxis therapy.

Methods:
This is a single center, retrospective cohort study. Chart review will be conducted for all eligible patients aged 18 years or older with a hematologic malignancy that were admitted to this institution between July 1, 2022 and July 31, 2023 and received 7 or more consecutive days of either isavuconazole or posaconazole for prophylaxis of fungal infections. Patients receiving an antifungal agent for definitive treatment only of fungal infections during this time period will be excluded. The clinical features and risk factors for bIFIs in this patient population will be assessed.

Results:
Results to be presented.

Discussion/

Conclusions:
Conclusions to be presented.

References (must also be included in final poster): 1. NCCN Guidelines. Prevention and Treatment of Cancer-Related Infections. Version 1.2023.
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