Background: Aspergillus infections pose the toughest infectious challenges to the clinician caring for hematopoietic cell transplant recipients. About 15% of patients become infected, with a case fatality rate of approximately 65%. To date, no effective prophylactic strategies have been developed.
Methods: Voriconazole, a recently licensed extended-spectrum azole, with demonstrated efficacy against aspergillus, is currently being tested as a potential prophylactic agent against aspergillus and other invasive fungal infections. Logistic issues--such as patient selection, choice of comparator, blinding of study drugs, duration of study drug administration, and how to handle empirical amphotericin B for possible invasive fungal infections--and analytic concerns, including choice and definition of the primary end point and the potential confounding effect of informative censoring (as a result of noninfectious events), were considered in the design of the clinical trial.
Results: The trial is now under way, with a projected 3-year enrollment period.
Conclusions: Each design decision shaped the trial in a way that permitted certain questions to be answered while not allowing others to be addressed. Once completed, the trial's results must be interpreted in light of these design details.