Penetration of micafungin into the burn eschar in patients with severe burns

Micafungin (MCFG) concentrations in the plasma and in burn eschar were investigated after daily intravenous infusion (1 h) of MCFG (200 mg) in three patients with severe burns. MCFG treatment was initiated more than 72 h after the burn injuries. The MCFG concentrations in the plasma were determined at the end of the first administration of MCFG, immediately before the second dosing, at the end of the MCFG infusion after at least 4 days from the initial treatment, and immediately before the subsequent dosing using high-performance liquid chromatography. In addition, the trough levels in burn eschar after both the initial administration and repeated administration were measured. The peak and trough levels in the plasma were comparable to or slightly lower than the reported values in healthy volunteers. The mean (range) MCFG concentrations in the burn eschar after initial administration and repeated administration were 1.41 μg/mL (<0.1-3.98 μg/mL) and 6.65 μg/mL (1.10-14.81 μg/mL), respectively. In most cases, the MCFG concentrations in the burn eschar, especially after repeated administration, were higher than the reported MIC ₉₀ of MCFG against the clinically important pathogenic species of Candida and Aspergillus. These results suggest that MCFG is capable of penetrating burn eschar.