G. Abruzzo, C. Gill, A. Flattery
Sep 1, 2000
Citations
4
Influential Citations
154
Citations
Quality indicators
Journal
Antimicrobial Agents and Chemotherapy
Abstract
ABSTRACT The in vivo efficacy of the echinocandin antifungal caspofungin acetate (caspofungin; MK-0991) was evaluated in models of disseminated aspergillosis and candidiasis in mice with cyclophosphamide (CY)-induced immunosuppression. Caspofungin is a 1,3-β-d-glucan synthesis inhibitor efficacious against a number of clinically relevant fungi including Aspergillusand Candida species. Models of CY-induced transient or chronic leukopenia were used with once daily administration of therapy initiated 24 h after microbial challenge. Caspofungin was effective in treating disseminated aspergillosis in mice that were transiently leukopenic (significant prolongation of survival at doses of ≥0.125 mg/kg of body weight and a 50% protective dose [PD50] of 0.245 mg/kg/day at 28 days after challenge) or chronically leukopenic (50 to 100% survival at doses of ≥0.5 mg/kg and PD50s ranging from 0.173 to 0.400 mg/kg/day). Caspofungin was effective in the treatment and sterilization ofCandida infections in mice with transient leukopenia with a 99% effective dose based on reduction in log10 CFU ofCandida albicans/gram of kidneys of 0.119 mg/kg and 80 to 100% of the caspofungin-treated mice having sterile kidneys at caspofungin doses from 0.25 to 2.0 mg/kg. InCandida-infected mice with chronic leukopenia, caspofungin was effective at all dose levels tested (0.25 to 1.0 mg/kg), with the log10 CFU of C. albicans/gram of kidneys of caspofungin-treated mice being significantly lower (>99% reduction) than that of sham-treated mice from day 4 to day 28 after challenge. Also, 70 to 100% of the caspofungin-treated, chronic leukopenic mice had sterile kidneys at caspofungin doses of 0.5 to 1.0 mg/kg from day 8 to 28 after challenge. Sterilization of Candida infections by caspofungin in the absence of host leukocytes provides compelling in vivo evidence for fungicidal activity against C. albicans. Further human clinical trials with caspofungin against serious fungal infections are in progress.