title: Comparative pharmacodynamics of amphotericin B lipid complex and liposomal amphotericin B in a murine model of pulmonary mucormycosis.
abstract: We compared the kinetics of amphotericin B (AMB) lung accumulation and fungal clearance by liposomal amphotericin B (L-AMB) and amphotericin B lipid complex (ABLC) in a neutropenic murine model of invasive pulmonary mucormycosis (IPM). Immunosuppressed BALB/c mice were inoculated with 1 x 10(6) Rhizopus oryzae spores and administered L-AMB or ABLC at daily intravenous doses of 1, 5, or 10 mg/kg of body weight for 5 days starting 12 h after infection. At a dose of 10 mg/kg/day, both L-AMB and ABLC were effective at reducing the R. oryzae lung fungal burden and achieved lung tissue concentrations exceeding the isolate mean fungicidal concentration (MFC) of 8 microg/ml by 72 h. When ABLC was dosed at 5 mg/kg/day, the ABLC-treated animals had significantly higher AMB lung concentrations than the L-AMB treated animals at 24 h (6.64 and 1.44 microg/g, respectively; P = 0.013) and 72 h (7.49 and 1.03 microg/g, respectively; P = 0.005), and these higher concentrations were associated with improved fungal clearance, as determined by quantitative real-time PCR (mean conidial equivalent of R. oryzae DNA per lung, 4.44 +/- 0.44 and 6.57 +/- 0.74 log(10), respectively; P < 0.001). Analysis of the AMB tissue concentration-response relationships revealed that the suppression of R. oryzae growth in the lung required tissue concentrations that approached the MFC for the infecting isolate (50% effective concentration, 8.19 microg/g [95% confidence interval, 2.81 to 18.1 microg/g]). The rates of survival were similar in the animals treated with L-AMB and ABLC at 10 mg/kg/day. These data suggest that higher initial doses may be required during L-AMB treatment than during ABLC treatment of experimental IPM.
authors.affiliation: University of Houston College of Pharmacy, Texas Medical Center Campus, 1441 Moursund Street, Unit 424, Houston, TX 77030, USA. rlewis@uh.edu
authors.forename: Russell E
authors.initials: RE
authors.lastname: Lewis
authors.forename: Nathan D
authors.initials: ND
authors.lastname: Albert
authors.forename: Guangling
authors.initials: G
authors.lastname: Liao
authors.forename: Jingguo
authors.initials: J
authors.lastname: Hou
authors.forename: Randall A
authors.initials: RA
authors.lastname: Prince
authors.forename: Dimitrios P
authors.initials: DP
authors.lastname: Kontoyiannis
mesh_terms: D000666:Amphotericin B / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D000935:Antifungal Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D004195:Disease Models, Animal; D006801:Humans; D008168:Lung / Q000382:microbiology; D008172:Lung Diseases, Fungal / Q000188:drug therapy* / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008826:Microbial Sensitivity Tests; D009091:Mucormycosis / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality; D012233:Rhizopus / Q000187:drug effects*; D016896:Treatment Outcome
chemical_list: D000935:Antifungal Agents; C068538:liposomal amphotericin B; D000666:Amphotericin B