Posaconazole Prophylaxis in Experimental Azole-Resistant Invasive Pulmonary Aspergillosis

Abstract

ABSTRACTWe investigated the efficacy of posaconazole prophylaxis in preventing invasive aspergillosis due to azole-resistantAspergillus fumigatusisolates. Using a neutropenic murine model of pulmonary infection, posaconazole prophylaxis was evaluated using three isogenic clinical isolates, with posaconazole MICs of 0.063 mg/liter (wild type), 0.5 mg/liter (F219I mutation), and 16 mg/liter. A fourth isolate harboring TR34/L98H (MIC of 0.5 mg/liter) was also tested. Posaconazole prophylaxis was effective inA. fumigatuswith posaconazole MICs of ≤0.5 mg/liter, where 100% survival was reached. However, breakthrough infection was observed in mice infected with the isolate for which the posaconazole MIC was >16 mg/liter.