Open AccessPharmacokinetics and in vivo activity of liposome-encapsulated gentamicin
Author(s) -
Christine E. Swenson,
Kathy A. Stewart,
Janis L. Hammett,
William E. Fitzsimmons,
Richard S. Ginsberg
Publication year - 1990
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.34.2.235
Subject(s) - liposome , gentamicin , pharmacokinetics , in vivo , pharmacology , spleen , gentamicin sulfate , mononuclear phagocyte system , aminoglycoside , antibiotics , drug carrier , medicine , phosphatidylcholine , chemistry , drug , biology , immunology , microbiology and biotechnology , biochemistry , phospholipid , membrane
Gentamicin sulfate was encapsulated in liposomes composed solely of egg phosphatidylcholine and administered via intravenous injection to rats and mice. The total gentamicin activity (regardless of whether it was free or liposome associated) in serum and selected tissues was determined for 24 h (serum) or up to 15 weeks (tissues) by using a microbiological assay. The mean half-lives in serum of a single 20-mg/kg dose of free (nonencapsulated) gentamicin in mice and rats were estimated to be 1.0 and 0.6 h, respectively, whereas a similar dose of encapsulated drug had apparent mean half-lives of 3.8 h in mice and 4.0 h in rats. In both species, the apparent half-life in serum of the liposomal formulation increased as the dose increased. Liposome encapsulation resulted in higher and more prolonged activity in organs rich in reticuloendothelial cells (especially spleen and liver). In acute septicemia infections in mice, the liposomal formulation showed enhanced prophylactic activity (as determined by calculation of the 50% protective dose). In a model of murine salmonellosis, liposomal gentamicin greatly enhanced survival when given as a single dose (10 mg/kg) at 1 or 2 days after infection as well as up to 7 days before infection.