Caspofungin acetate for treatment of invasive fungal infections

OBJECTIVE: To briefly discuss the changing epidemiology of fungal infections and review currently available agents; provide a review of caspofungin; and discuss its pharmacology, pharmacokinetics, dosing guidelines, safety and efficacy, and role in the treatment of invasive fungal infections as it relates to current antifungal therapy. DATA SOURCES: A MEDLINE (1966 to August 2002) database search using key words caspofungin, echino candins, fungal infections, and invasive aspergillosis, was completed to identify relevant articles including reviews, recent studies, treatment guidelines, and data from Merck and Company. STUDY SELECTION: In vitro studies and all clinical trials were evaluated to summarize the clinical efficacy and safety of caspofungin. DATA SYNTHESIS: The incidence of fungal infections is increasing as the population at risk expands. Cost, resistance, and morbidity and mortality are key issues. Adding to the antifungal armamentarium is necessary to address these therapeutic dilemmas. Caspofungin is the first member of a new class of antifungal agents, the echinocandins, to be approved for clinical use. Caspofungin is classified as a glucan synthase inhibitor and represents a class of agents with a novel mechanism of action. Unlike currently available agents (polyenes, pyrimidines, azoles) that exert their effect on the fungal cell membrane, the echinocandins are the first agents to inhibit fungal cell wall synthesis. Caspofungin exhibits activity against Aspergillus spp. and Candida spp., including nonalbicans species. Data from clinical trials demonstrate that caspofungin is effective in patients with invasive aspergillosis as well as candida esophagitis. Its Food and Drug Administration-approved indication is limited to invasive aspergillosis refractory to or intolerant of current therapy. CONCLUSIONS: Caspofungin has activity against Aspergillus spp. as well as a variety of Candida spp. Clinical data support its usefulness in the treatment of invasive aspergillosis and select candida infections. As additional clinical data become available, it seems likely that the therapeutic role of caspofungin will expand.