This study is to evaluate safety and prophylaxis effect of micafungin after hematopoietic stem cell transplantation. Micafungin is administered until confirmation of neutrophil engraftment or treatment failure.

The purpose of this study is to evaluate absence of proven, probable, possible, suspected invasive fungal disease (IFDs) through the end of prophylaxis therapy and during 4 weeks after stopping of micafungin prophylaxis after allogeneic hematopoietic stem cell transplantation in pediatric and adolescent neutropenia patients. Patients will receive micafungin until the earliest of the following: 1) neutrophil engraftment; 2) development of proven, provable, possible or suspected invasive fungal disease; 3) development of unacceptable drug toxicity; 4) withdrawal from study participation or discontinuation of study treatment. Safety profile of micafungin is also evaluated.

Inclusion Criteria:

• Patients will receive allogeneic hematopoietic stem cell transplantation

Exclusion Criteria:

• Aspartate transaminase or alanine transaminase level > 5 times UNL
• Bilirubin > 2. 5 times UNL
• History of allergy, sensitivity, or any serious reaction to an echinocandin
• Invasive fungal disease at the time of enrolment
• Systemic antifungal therapy within 72 hrs before administration of the first dose of study drug
• Positive pregnancy test