Farmacodinamia y farmacocinética de la micafungina en adultos, niños y neonatos / Pharmacodynamics and pharmacokinetcis of micafungin in adults, children and neonate

RESUMEN

Antecedentes: Las infecciones fúngicas son una causa importante de morbilidad y mortalidad en los pacientes inmunodeficientes. A pesar que en los últimos años se han desarrollado nuevos fármacos antifúngicos, el tratamiento de estas infecciones sigue siendo problemático. Objetivos: Revisar la farmacodinamia y la farmacocinética de una nueva equinocandina: micafungina. Métodos: Se ha realizado una revisión simple utilizando una búsqueda bibliográfica en las fuentes habituales (EBSCO Open Journals, Ovid Online, Proquest Medical Library, PubMed/Medline, Science Direct, Springer Links y Wiley Interscience) desde el año 2000 hasta 2008. Adicionalmente, se han incluido los libros de resúmenes de Interscience Conference on Antimicrobial Agents and Chemotherapy and the Infectious Diseases Society of America celebradas desde 1998 hasta 2008. Resultados: La micafungina es una equinocandina con un potente mecanismo de acción: inhibe el enzima β-1,3-D-glucano sintasa e interfiere en la síntesis de la pared celular. Este fármaco comparte con la caspofungina un idéntico espectro in vitro frente a Candida albicans, especies de Candida diferentes de C. albicans y Aspergillus. Debido a la limitada biodisponibilidad oral, la micafungina se administra únicamente por vía parenteral. Se caracteriza por una farmacocinética lineal y por presentar pocos efectos adversos. La micafungina se metaboliza mínimamente por el citocromo P-450 y presenta pocas interacciones farmacológicas. No requiere reducir dosis en fracaso renal, ni en fracaso hepático leve o moderado. Conclusiones: La micafungina presenta un perfil farmacodinámico y farmacocinético que permite su administración de modo seguro, con mínimas interacciones medicamentosas y sin necesidad de ajuste de dosis en presencia de fracaso renal o hepático (AU)

ABSTRACT

Background: Invasive fungal infections are a significant cause of morbidity and mortality among immuno- compromised patients. Although several new antifungal agents have been developed in the past few years, the management of serious fungal infections continues to be problematic. Aims: To review the pharmacodynamics and pharmacokinetics of a new antifungal agent: micafungin. Methods: A systematic review of biomedic databases (EBSCO Open Journals, Ovid Online, Proquest Medical Library, PubMed/Medline,, Science Direct, Springer Links and Wiley Interscience) has been performed. Search was conducted from 2000 to 2008. Supplementary sources included abstracts from the Interscience Conference on Antimicrobial Agents (ICAAC) and Chemotherapy and the Infectious Diseases Society of America (IDSA) from 1998 to 2008. Results: Micafungin has a potent mechanism of action: inhibits β-1,3-D-glucan synthase interfering with fungal cell wall synthesis. This agent shares with caspofungin an identical spectrum of in vitro activity against Candida albicans, non-albicans Candida species, and Aspergillus. Due to the limited oral availability, micafungin is available for parenteral administration only. Micafungin is characterized by a linear pharmacokinetic profile and substantially fewer toxic effects. Micafungin is a poor substrate for the cytochrome P450 enzymes, and compared to azoles, fewer drug interactions have been described. No dose reduction is required in renal impairment or in mild to moderate liver failure. Conclusions: The pharmacodynamic and pharmacokinetic profiles of micafungin imply that this drug is a safe alternative for the treatment of fungal infections. Micafungin can be safely co-administered with most drugs without the need for dosage adaptation even in patients with renal o liver function impairment (AU)