Biol. Pharm. Bull. 29(9) 1886—1891 (2006)

tion mechanism from existing antifungal agents, and its clinical efficacy is expected. MCFG exhibits a wide antifungal spectrum against Candida and Apergillus species in vitro by inhibiting biosynthesis of the major fungal cell wall component, 1,3-b-D-glucan. Its superior transfer to the lung may be highly effective for prevention and treatment of pulmonary mycosis. Clinically, MCFG is particularly important for treatment of pulmonary aspergillosis, which is problematic in patients with blood diseases. We previously reported that a 150 mg or higher daily dose is necessary for treatment of pulmonary aspergillosis with MCFG alone for patients with blood diseases from our clinical experience. However, we often encounter cases in which no therapeutic effect is obtained despite MCFG being administered at a sufficient dose, and a dose increase of MCFG or switch to other drugs is necessary. Moreover, no clear basis for dose adjustment is available for MCFG dose reduction in patients with severe impairment of renal or liver function. If the blood MCFG level does not reach the therapeutic level and delays treatment of pulmonary aspergillosis, it may have a major influence on patient survival. Clarification of the effective blood concentration of MCFG by evaluating its clinical effect enables rapid and accurate treatment. Establishment of an appropriate dose is also useful for reducing the risk of adverse effects, such as MCFG-induced impairment of liver function. Aiming for the rapid and safe treatment of pulmonary aspergillosis, we established new clinical diagnostic criteria of mycosis and a clinical improvement rating associated with MCFG administration, and investigated the effective blood concentration of MCFG for mycosis. The effective blood trough level of MCFG for pulmonary aspergillosis, which has not previously been established, was determined. The findings promoted rapid and safe treatment of pulmonary aspergillosis in patients with blood diseases. MATERIALS AND METHODS