[Why might micafungin be the drug of choice in pediatric patients?]

Micafungin is an echinocandin approved by the European Medicines Evaluation Agency for the treatment of invasive candidiasis in children, including premature infants born before 29 weeks of pregnancy, and as prophylaxis in children undergoing hematopoietic stem-cell transplantation or patients at risk of prolonged neutropenia. This drug has good activity in several Candida spp., including those resistant to fluconazole. Although micafungin is active against Aspergillus spp., it has been used mainly in combination therapy for invasive aspergillosis. There is ample information on the use of micafungin in children, including neonates, and this drug is the only echinocandin approved for use in infants aged less than 3 months. The efficacy, pharmacokinetics and safety of micafungin have been evaluated in phase II and III clinical trials in children, in which its efficacy and safety were demonstrated in comparison with liposomal amphotericin B and fluconazole. The pharmacokinetic profile of micafungin in children allows once daily intravenous administration, with greater clearance than in adults, and consequently pediatric doses are relatively higher. The most appropriate dose in children weighing less than 40 kg is 2 mg/kg/day in the treatment of invasive candidiasis and 1 mg/kg/day as prophylaxis in children undergoing hematopoietic stem-cell transplantation. Doses in neonates should be higher. In premature infants, the most appropriate doses to achieve levels in the brain parenchyma are 7 mg/kg/day and 10 mg/kg/day in those weighing more and less than 1,000 g, respectively. Micafungin has few drug-drug interactions and an acceptable safety profile. Withdrawal of this drug due to adverse effects is rare, although transaminase monitoring is recommended during treatment, as well as evaluation of the risk-benefit balance in patients with liver disease or concomitant administration of hepatotoxic drugs.