Micafungin Is Extremely Effective Against Fungal Infections Complicating Hematological Malignancies: Report of a Multicenter Study by N-FISH (Niigata Fungal Infection Study Group in Hematology).

[Background]Micafungin (MCFG) is a candin antifungal agent, and was marketed in Dec. 2002 in Japan and in Apr. 2005 in the United States. The Niigata Fungal Infection Study Group in Hematology (N-FISH) performed a multicenter prospective study to clarify the therapeutic effects of MCFG on deep fungal infections complicating hematological malignancies.

[Methods]A total of 36 pts. who had been treated in centers belonging to N-FISH between Oct. 2003 and Apr. 2005 were included in this study. They consisted of 14 men and 22 women with a mean age of 53.5 years: 14 pts. with AML, 10 pts. with malignant lymphoma, 6 pts. with ALL, and 6 pts with other diseases. They had a proven fungal infection, or were suspected of having a fungal infection because of fever unresponsive to antimicrobial agents or from laboratory data. Three of them had a proven infection, and 33 were suspected of having a fungal infection. Three of these 33 pts. failed to respond to fluconazole. As a rule, MCFG was administered for more than 14 days until infectious symptoms improved or disappeared. When MCFG was judged ineffective because of the worsening of clinical symptoms despite the administration of MCFG, or when the administration of MCFG was judged difficult because of adverse effects, the drug was discontinued or replaced by other drugs. Two pts. orally received amphotericin B syrup singly.

[Results]The mean dose of MCFG was 2.6 mg/kg (1.5–4.2 mg/kg), and the mean duration of administration was 15.9 days (5–85 days). Complete or partial response was achieved in 31 (86.1%) of the 36 pts., who showed improvements in infectious symptoms. In 4 pts, MCFG was discontinued because of insufficient effects. There were no breakthrough fungal infections within 7 days after the completion of MCFG therapy. Of the 36 pts., 31 (86.1%) and 24 (66.7%) survived 1 and 3 months after MCFG therapy, respectively. The cause of death was exacerbation of the primary disease, and not exacerbation or the onset of a fungal infection. Eight adverse events occurred in 7 pts.: hypoglycemia in 1, liver dysfunction in 3, eosinophilia in 1, kidney dysfunction in 2, and hypokalemia in 1. In 1 of the 3 pts. with liver dysfunction (grade 3), MCFG therapy was discontinued, with rapid improvement of the liver dysfunction. All other adverse events were mild, allowing continued MCFG therapy.

[Conclusion]This multicenter study demonstrated the effectiveness and safety of MCFG therapy for deep fungal infections complicating hematological malignancies. The results suggest that MCFG should be promptly used for fever associated with a fungal infection complicating hematological malignancies.