The purpose of this study is to determine the efficacy and safety of micafungin (FK463) versus liposomal amphotericin B (AmBisome) in treating neutropenic and non-neutropenic patients with confirmed invasive candidiasis or candidemia. Enrollment will include adult and pediatric patients.

A phase III, multicenter, double-blind, comparative, parallel, randomized study. Enrollment will include adult and pediatric patients. The adult population is sized to test for non-inferiority. For the pediatric population, descriptive analyses are planned.

Inclusion Criteria:

Patients either non-neutropenic with absolute neutrophil counts >= 500 cells/mm3 or neutropenic with absolute neutrophil counts < 500 cells/mm3 must have:

• Candidemia or invasive candidiasis,
• Confirmation and typical clinical signs and symptoms by fungal culture and/or histology,
• Positive culture obtained no more than four days prior to the first dose of study medication.

Exclusion Criteria:

• Patient is pregnant or nursing
• Patients with evidence of liver disease as defined by: a) SGOT/AST or SGPT/ALT > 10 times the upper limit of normal (ULN); or b) Total bilirubin > 5 times ULN.
• Patients whose sole diagnosis is oropharyngeal and/or esophageal candidiasis and/or with positive cultures of urine specimens, sputum specimens, bronchoalveolar-lavage specimens or samples from indwelling drains.
• Patients who have received prophylactic/empiric therapy with azoles or conventional amphotericin B for more than three days within one week prior to enrollment. Neutropenic patients, however, may have received prophylactic azoles without time restrictions.