Cyclodextrins and liposomes have been used in recent years as drug delivery vehicles, improving the bioavailability and therapeutic efficacy of many poorly water-soluble drugs. In this study, we used two approaches to enhance the availability of the poorly water-soluble antibiotic, clarithromycin, by inclusion complex formation and by liposome-encapsulation. We examined the efficacies of these formulations against Mycobacterium avium complex (MAC) in human peripheral blood monocyte-derived macrophages. The water solubility of clarithromycin was enhanced by about 700-fold by complexation with cyclodextrin. The use of a rapid radiometric (BACTEC) method for the detection of MAC growth and susceptibility showed identical MICs against MAC for both the free and complexed drug. The anti-MAC efficacy of the cyclodextrin complex of clarithromycin in macrophages was slightly lower than the free drug, probably due to the high stability of the inclusion complex. At higher drug concentrations, Liposome-encapsulated clarithromycin was slightly more effective against intracellular MAC growth than the free drug.
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http://dx.doi.org/10.1016/s0378-5173(02)00552-5 | DOI Listing |
Antimicrob Agents Chemother
June 2013
Novel Drug and Vaccine Delivery Systems Facility, Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada.
We investigated the efficacy and safety of liposomal clarithromycin formulations with different surface charges against clinical isolates of Pseudomonas aeruginosa from the lungs of cystic fibrosis (CF) patients. The liposomal clarithromycin formulations were prepared by the dehydration-rehydration method, and their sizes were measured using the dynamic-light-scattering technique. Encapsulation efficiency was determined by microbiological assay, and the stabilities of the formulations in biological fluid were evaluated for a period of 48 h.
View Article and Find Full Text PDFMethods Enzymol
August 2005
Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of Granada, Granada, Spain.
Encapsulation of certain antibiotics in liposomes can enhance their effect against microorganisms invading cultured cells and in animal models. We describe the incorporation of amikacin, streptomycin, ciprofloxacin, sparfloxacin, and clarithromycin in a variety of liposomes. We delineate the methods used for the evaluation of their efficacy against Mycobacterium avium-intracellulare complex (MAC) infections in macrophages and in the beige mouse model of MAC disease.
View Article and Find Full Text PDFInt J Pharm
January 2003
Department of Microbiology, University of the Pacific, 2155 Webster Street, San Francisco, CA 94115, USA.
Cyclodextrins and liposomes have been used in recent years as drug delivery vehicles, improving the bioavailability and therapeutic efficacy of many poorly water-soluble drugs. In this study, we used two approaches to enhance the availability of the poorly water-soluble antibiotic, clarithromycin, by inclusion complex formation and by liposome-encapsulation. We examined the efficacies of these formulations against Mycobacterium avium complex (MAC) in human peripheral blood monocyte-derived macrophages.
View Article and Find Full Text PDFClin Infect Dis
April 1994
Department of Medicine, Rush Medical College/Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois 60612.
Perhaps the most important recent advance in the field of infections due to the Mycobacterium avium complex (MAC) is the identification and development of more effective agents for the treatment and prevention of disseminated disease. These agents include clarithromycin, azithromycin, rifabutin and other rifamycins, ethambutol, clofazimine, fluoroquinolones, amikacin, and liposome-encapsulated gentamicin. Most clinicians currently use multidrug therapy to maximize efficacy and to minimize the emergence of resistance.
View Article and Find Full Text PDFAntimicrob Agents Chemother
March 1994
Department of Pharmacy, Hartford Hospital, Connecticut 06115.
The therapeutic efficacies of liposome-encapsulated ofloxacin and clarithromycin against Mycobacterium avium-M. intracellulare (MAI) were evaluated in a model of intramacrophage infection. Liposome encapsulation was found to markedly enhance the uptake of each of the drugs by human macrophages.
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