Isavuconazole for the Treatment of Invasive Fungal Disease in Hematology Patients: A Real-World Retrospective Study on Efficacy and Safety

Invasive fungal disease (IFD) remains a life-threatening complication in patients with hematological diseases. Isavuconazole was approved by the FDA for primary treatment of invasive aspergillosis and mucormycosis. While clinical trials have demonstrated its efficacy, data on its use in hematology patients remain limited. This study aims to evaluate the real-world effectiveness and safety of isavuconazole in this population. We conducted a single-center, retrospective study of hematology patients who received isavuconazole for IFD between 1 June 2022, and 31 July 2024, at West China Hospital, Sichuan University. A total of 66 patients with proven (<i>n</i> = 9), probable (<i>n</i> = 17), or possible (<i>n</i> = 40) IFD were included in the study. Acute leukemia (AL) was the most common underlying disease, affecting 27 patients (40.9%), followed by non-Hodgkin's lymphoma (NHL) and myelodysplastic syndrome (MDS). Over 80.0% of patients received oral isavuconazole. At 6 weeks of follow-up, a favorable response was observed in 57.6% of patients, increasing to 71.2% at 12 weeks. Factors associated with achieving complete response in isavuconazole treatment included receiving isavuconazole as primary treatment (OR = 0.10, <i>p</i> = 0.01) and reaching complete/partial remission (CR/PR) of the primary hematological disease (OR = 0.07, <i>p</i> = 0.003). The all-cause mortality rates were under 30.0%. The use of isavuconazole as primary antifungal therapy (<i>p</i> < 0.05) and achieving CR/PR in the underlying hematological disease (<i>p</i> < 0.05) were two independent predictors of improved clinical outcomes. Adverse events were reported in 33.3% of patients, and no adverse events led to discontinuation of treatment. Our study demonstrated that isavuconazole is an effective and well-tolerated treatment for IFD in hematology patients. The oral formulation provided comparable efficacy and enhanced compliance, potentially leading to improved outcomes and optimizing the management strategy. The generalizability of our findings may be limited by the single-center, retrospective nature; further validation through prospective, multi-center studies is needed.