scholarly journals Behavior of amphotericin B lipid complex in plasma in vitro and in the circulation of rats.

1997 ◽  
Vol 41 (5) ◽  
pp. 886-892 ◽  
Author(s):  
R Bhamra ◽  
A Sa'ad ◽  
L E Bolcsak ◽  
A S Janoff ◽  
C E Swenson
Keyword(s):  
Amphotericin B ◽  
Therapeutic Index ◽  
Parent Material ◽  
Protein Distribution ◽  
Time Curve ◽  
Lipid Complex ◽  
Amphotericin B Lipid Complex ◽  
Reduced Toxicity

Amphotericin B lipid complex (ABLC) shows reduced toxicity relative to that of amphotericin B deoxycholate (AmB-d) while maintaining antifungal activity. Rat blood or plasma was spiked with ABLC in vitro. Released amphotericin B was separated from the parent material by centrifugation. At early times (0 to 15 min) most (approximately 90%) of the amphotericin B was complexed. The amount of released amphotericin B increased gradually in a time- and temperature-dependent fashion. The released amphotericin B was associated with plasma lipoprotein and nonlipoprotein proteins. The area under the concentration-time curve from 0 to 24 h for total amphotericin B in whole blood of rats given a single intravenous bolus dose of 1 mg of ABLC per kg of body weight was fourfold lower than that in rats given 1 mg of AmB-d per kg. The complexed amphotericin B was rapidly removed from the circulation and was distributed to the tissues in these rats. Other rats were treated intravenously with ABLC (10 mg/kg/day) or AmB-d (0.5 mg/kg/day) daily for 15 days. Blood was collected at 15 and 180 min after administration of the last dose. The total levels of amphotericin B in the blood of the group given ABLC were about three to five times those in the group given AmB-d, and the concentration of released, protein-bound amphotericin B in the plasma of the group given ABLC was about one to two times that observed for the group given AmB-d, despite the 20-fold difference in dose. The relative protein distribution of amphotericin B in plasma was similar after ABLC or AmB-d administration under these steady-state conditions in vivo. The rapid uptake of complexed amphotericin B by tissues and the very low levels of circulating protein-bound amphotericin B in plasma after the administration of ABLC may explain, in part, the reduced toxicity and enhanced therapeutic index of this preparation.

scholarly journals In Vitro and In Vivo Antifungal Activity of Amphotericin B Lipid Complex: Are Phospholipases Important?

1998 ◽  
Vol 42 (4) ◽  
pp. 767-771 ◽  
Author(s):  
Christine E. Swenson ◽  
Walter R. Perkins ◽  
Patricia Roberts ◽  
Imran Ahmad ◽  
Rachel Stevens ◽  
...  
Keyword(s):  
Antifungal Activity ◽  
Amphotericin B ◽  
Vascular Tissue ◽  
Therapeutic Index ◽  
Test Material ◽  
Lipid Complex ◽  
In Vitro Susceptibility ◽  
Amphotericin B Lipid Complex

ABSTRACT Amphotericin B lipid complex for injection (ABLC) is a suspension of amphotericin B complexed with the lipidsl-α-dimyristoylphosphatidylcholine (DMPC) andl-α-dimyristoylphosphatidylglycerol. ABLC is less toxic than amphotericin B deoxycholate (AmB-d), while it maintains the antifungal activity of AmB-d. Active amphotericin B can be released from ABLC by exogenously added (snake venom, bacteria, orCandida-derived) phospholipases or by phospholipases derived from activated mammalian vascular tissue (rat arteries). Such extracellular phospholipases are capable of hydrolyzing the major lipid in ABLC. Mutants of C. albicans that were resistant to ABLC but not AmB-d in vitro were deficient in extracellular phospholipase activity, as measured on egg yolk agar or as measured by their ability to hydrolyze DMPC in ABLC. ABLC was nevertheless effective in the treatment of experimental murine infections produced by these mutants. Isolates of Aspergillus species, apparently resistant to ABLC in vitro (but susceptible to AmB-d), were also susceptible to ABLC in vivo. We suggest that routine in vitro susceptibility tests with ABLC itself as the test material may not accurately predict the in vivo activity of ABLC and that the enhanced therapeutic index of ABLC relative to that of AmB-d in vivo may be due, in part, to the selective release of active amphotericin B from the complex at sites of fungal infection through the action of fungal or host cell-derived phospholipases.

In vitro and in vivo antifungal activities of liposomal amphotericin B, and amphotericin B lipid complex

1994 ◽  
Vol 128 (1) ◽  
pp. 13-17 ◽  
Author(s):  
Kotaro Mitsutake ◽  
Shigeru Kohno ◽  
Yoshitsugu Miyazaki ◽  
Tetsuhiro Noda ◽  
Haruko Miyazaki ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Liposomal Amphotericin ◽  
Liposomal Amphotericin B ◽  
Lipid Complex ◽  
Antifungal Activities ◽  
Amphotericin B Lipid Complex

scholarly journals Dose Range Evaluation of Liposomal Nystatin and Comparisons with Amphotericin B and Amphotericin B Lipid Complex in Temporarily Neutropenic Mice Infected with an Isolate of Aspergillus fumigatus with Reduced Susceptibility to Amphotericin B

1999 ◽  
Vol 43 (11) ◽  
pp. 2592-2599 ◽  
Author(s):  
David W. Denning ◽  
Peter Warn
Keyword(s):  
Aspergillus Fumigatus ◽  
Amphotericin B ◽  
Dose Range ◽  
Respiratory Arrest ◽  
Optimal Dosage ◽  
Lipid Complex ◽  
Amphotericin B Deoxycholate ◽  
Liver And Kidney ◽  
Amphotericin B Lipid Complex

ABSTRACT Using an isolate of Aspergillus fumigatus that is less susceptible in vivo to amphotericin B than most other isolates, we compared different doses of liposomal nystatin (L-nystatin), liposomal amphotericin B (L-amphotericin), and amphotericin B lipid complex (ABLC) with amphotericin B deoxycholate. Four experiments with intravenously infected neutropenic mice were conducted. A dose of L-nystatin at 10 mg/kg of body weight was toxic (the mice had fits or respiratory arrest). The optimal dosage of L-nystatin was 5 mg/kg daily on days 1, 2, 4, and 7 (90% survival). This was superior to L-amphotericin (5 mg/kg [P = 0.24] and 1 mg/kg [P < 0.0001]), ABLC (5 mg/kg [P = 0.014] and 1 mg/kg [P < 0.0001]), and amphotericin B deoxycholate (5 mg/kg [P = 0.008]). In terms of liver and kidney cultures, L-nystatin (5 mg/kg) was superior to all other regimens (P = 0.0032 and <0.0001, respectively). Higher doses of L-amphotericin (25 and 50 mg/kg) in one earlier experiment were more effective (100% survival) than 1 mg of L-amphotericin per kg and amphotericin deoxycholate (5 mg/kg) in terms of mortality and both liver and kidney culture results and to L-amphotericin (5 mg/kg) in terms of liver and kidney culture results only. ABLC (25 mg/kg) given daily for 7 days was superior to ABLC (50 mg/kg [P = 0.03]) but not to ABLC at 5 mg/kg or amphotericin B deoxycholate in terms of mortality, although it was in terms of liver and kidney culture results. No dose-response for amphotericin B (5 and 1 mg/kg) was demonstrable. In conclusion, in this stringent model, high doses of L-amphotericin and ABLC could overcome reduced susceptibility to amphotericin B deoxycholate, but all were inferior to 5- to 10-fold lower doses of L-nystatin.

scholarly journals Pharmacokinetics and Pharmacodynamics of Amphotericin B Deoxycholate, Liposomal Amphotericin B, and Amphotericin B Lipid Complex in an In Vitro Model of Invasive Pulmonary Aspergillosis

2010 ◽  
Vol 54 (8) ◽  
pp. 3432-3441 ◽  
Author(s):  
Jodi M. Lestner ◽  
Susan J. Howard ◽  
Joanne Goodwin ◽  
Lea Gregson ◽  
Jayesh Majithiya ◽  
...  
Keyword(s):  
Confocal Microscopy ◽  
Amphotericin B ◽  
Liposomal Amphotericin ◽  
Invasive Pulmonary Aspergillosis ◽  
Host Cells ◽  
Pulmonary Aspergillosis ◽  
Lipid Complex ◽  
Amphotericin B Deoxycholate ◽  
Amphotericin B Lipid Complex

ABSTRACT The pharmacodynamic and pharmacokinetic (PK-PD) properties of amphotericin B (AmB) formulations against invasive pulmonary aspergillosis (IPA) are not well understood. We used an in vitro model of IPA to further elucidate the PK-PD of amphotericin B deoxycholate (DAmB), liposomal amphotericin B (LAmB) and amphotericin B lipid complex (ABLC). The pharmacokinetics of these formulations for endovascular fluid, endothelial cells, and alveolar cells were estimated. Pharmacodynamic relationships were defined by measuring concentrations of galactomannan in endovascular and alveolar compartments. Confocal microscopy was used to visualize fungal biomass. A mathematical model was used to calculate the area under the concentration-time curve (AUC) in each compartment and estimate the extent of drug penetration. The interaction of LAmB with host cells and hyphae was visualized using sulforhodamine B-labeled liposomes. The MICs for the pure compound and the three formulations were comparable (0.125 to 0.25 mg/liter). For all formulations, concentrations of AmB progressively declined in the endovascular fluid as the drug distributed into the cellular bilayer. Depending on the formulation, the AUCs for AmB were 10 to 300 times higher within the cells than within endovascular fluid. The concentrations producing a 50% maximal effect (EC50) in the endovascular compartment were 0.12, 1.03, and 4.41 mg/liter for DAmB, LAmB, and ABLC, respectively, whereas, the EC50 in the alveolar compartment were 0.17, 7.76, and 39.34 mg/liter, respectively. Confocal microscopy suggested that liposomes interacted directly with hyphae and host cells. The PK-PD relationships of the three most widely used formulations of AmB differ markedly within an in vitro lung model of IPA.

In vitro and in vivo antifungal activities of ER-30346, a novel oral triazole with a broad antifungal spectrum.

1996 ◽  
Vol 40 (10) ◽  
pp. 2237-2242 ◽  
Author(s):  
K Hata ◽  
J Kimura ◽  
H Miki ◽  
T Toyosawa ◽  
T Nakamura ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Candida Glabrata ◽  
Candida Parapsilosis ◽  
Good Activity ◽  
Time Curve ◽  
Concentration Time ◽  
Wide Range ◽  
Systemic Infections

ER-30346 is a novel oral triazole with a broad spectrum of potent activity against a wide range of fungi. ER-30346, with MICs at which 90% of the strains tested are inhibited (MIC90s) ranging from 0.025 to 0.78 microgram/ml, was 4 to 32 times more active than itraconazole, fluconazole, and amphotericin B against Candida albicans, Candida parapsilosis, and Candida glabrata. Against Candida tropicalis, ER-30346, with an MIC90 of 12.5 micrograms/ml, was 2 to > 8 times more active than itraconazole and fluconazole, but was 16 times less active than amphotericin B. ER-30346 (MIC90, 0.78 microgram/ml) was four to eight times more active than fluconazole and amphotericin B and had activity comparable to that of itraconazole against Trichosporon beigelli. The MIC90s of ER-30346 were 0.10 microgram/ml for Cryptococcus neoformans and 0.39 microgram/ml for Aspergillus fumigatus. ER-30346 was 2 to 8 times more active than itraconazole and amphotericin B and 32 to > 256 times more active than fluconazole. ER-30346 also showed good activity against dermatophytes, with MICs ranging from 0.05 to 0.39 microgram/ml, and its activity was comparable to or 2 to 16 times higher than those of itraconazole and amphotericin B and > 32 times higher than that of fluconazole. In vivo activity was evaluated with systemic infections in mice. Against systemic candidiasis and cryptococcosis, ER-30346 was comparable in efficacy to fluconazole and was more effective than itraconazole. Of the drugs tested, ER-30346 was the most effective drug against systemic aspergillosis. We studied the levels of ER-30346 in mouse plasma. The maximum concentration of drug in plasma and the area under the concentration-time curve for ER-30346 showed good linearity over a range of doses from 2 to 40 mg/kg of body weight.

scholarly journals Serum pharmacology of amphotericin B applied in lipid emulsions.

1997 ◽  
Vol 41 (4) ◽  
pp. 728-732 ◽  
Author(s):  
V Heinemann ◽  
B Kähny ◽  
U Jehn ◽  
D Mühlbayer ◽  
A Debus ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Dose Range ◽  
Reticuloendothelial System ◽  
Subsequent Treatment ◽  
Pharmacokinetic Analysis ◽  
Lipid Emulsions ◽  
Time Curve ◽  
Lipid Aggregates

Application of amphotericin B in lipid emulsions (AmB/L) reduced membrane toxicity in vitro and decreased amphotericin B-associated toxic side effects in vivo when compared to that of amphotericin B applied in 5% glucose (AmB/G). Therefore, a comparative analysis of the pharmacological parameters of AmB/L and AmB/G was performed. Thirteen patients were analyzed, and nine of these patients received a subsequent treatment with AmB/G and AmB/L. In patients in both treatment groups amphotericin B showed a biphasic elimination from serum, with a prolonged terminal half-life of approximately 27 h. Patients treated with AmB/L showed significantly lower peak concentrations (44.2%; P = 0.008) and correspondingly lower area under the drug concentration-time curve (AUC) values (64.3%; P = 0.015) compared to the values for the same patients treated with AmB/G at a dose range of 0.6 to 1.5 mg/kg of body weight. The enhanced clearance of AmB/L may be due to a faster initial elimination of amphotericin B-lipid aggregates by the reticuloendothelial system. Lower peak concentrations and AUC values in serum and a correspondingly faster deposition of AmB/L in tissues may at least partly explain the lower toxicity of AmB/L. A comparative pharmacokinetic analysis with data for a single patient treated with AmB/L demonstrated that hemodialysis did not significantly affect the disposition of amphotericin B.

scholarly journals Comparative Efficacies, Toxicities, and Tissue Concentrations of Amphotericin B Lipid Formulations in a Murine Pulmonary Aspergillosis Model

2006 ◽  
Vol 50 (6) ◽  
pp. 2122-2131 ◽  
Author(s):  
Jon A. Olson ◽  
Jill P. Adler-Moore ◽  
Julie Schwartz ◽  
Gerard M. Jensen ◽  
Richard T. Proffitt
Keyword(s):  
Amphotericin B ◽  
High Performance ◽  
Therapeutic Index ◽  
Pulmonary Aspergillosis ◽  
Lipid Complex ◽  
Drug Concentrations ◽  
Kidney Morphology ◽  
Amphotericin B Lipid Complex ◽  
Effective Use ◽  
Lipid Formulations

ABSTRACT Invasive aspergillosis, an important cause of morbidity and mortality in immunosuppressed (IS) patients, is often treated with amphotericin B lipid formulations. In the present study, liposomal amphotericin B (L-AMB) and amphotericin B lipid complex (ABLC) were compared in treatment of murine pulmonary aspergillosis. Uninfected, IS mice were treated for 4 days with 1, 4, 8, or 12 mg L-AMB or ABLC/kg of body weight, and their lungs were analyzed by high-performance liquid chromatography for drug concentrations. IS mice intranasally challenged with Aspergillus fumigatus were treated with 12, 15, or 20 mg/kg L-AMB or ABLC and monitored for survival, fungal burden (CFU), and tissue drug concentration. Blood urea nitrogen (BUN) levels and kidney histopathology were determined for uninfected and infected mice given 15 or 20 mg/kg L-AMB or ABLC. The results showed that both drugs had therapeutic levels of drug (>3.0 μg/g) in the lungs of uninfected or infected mice, and 24 h after the last dose, ABLC levels were significantly higher than L-AMB levels (P < 0.02). L-AMB and ABLC at 12 mg/kg both produced 57% survival, but only L-AMB at 15 or 20 mg/kg further increased survival to 80 to 90%, with BUN levels and kidney morphology similar to those of controls. Survival at 15 or 20 mg/kg ABLC was not significantly different than that of controls, and BUN levels were significantly elevated, with tubular alterations in uninfected animals and acute necrosis in kidney tubules of infected animals. In conclusion, although both drugs were effective in prolonging survival at 12 mg/kg, the reduced nephrotoxicity of L-AMB increased its therapeutic index, allowing for its safe and effective use at 15 or 20 mg/kg.

scholarly journals Fungal Phospholipase Activity and Susceptibility to Lipid Preparations of Amphotericin B

2001 ◽  
Vol 45 (11) ◽  
pp. 3231-3233 ◽  
Author(s):  
Magnus Gottfredsson ◽  
Chad J. Jessup ◽  
Gary M. Cox ◽  
John R. Perfect ◽  
Mahmoud A. Ghannoum
Keyword(s):  
Candida Albicans ◽  
Cryptococcus Neoformans ◽  
Amphotericin B ◽  
Susceptibility Testing ◽  
Phospholipase Activity ◽  
Lipid Complex ◽  
In Vitro Susceptibility ◽  
Amphotericin B Lipid Complex ◽  
In Vitro Susceptibility Testing

ABSTRACT It has been postulated that phospholipases of fungal origin can affect in vitro susceptibility testing of amphotericin B lipid complex (ABLC). We used specific phospholipase-deficient mutants ofCandida albicans and Cryptococcus neoformans in susceptibility testing and demonstrated that extracellular fungal phospholipase activity does not influence the in vitro susceptibilities of these two fungi to ABLC.

Comparative in vitro Antifungal Activity of Amphotericin B Lipid Complex, Amphotericin B and Fluconazole

Chemotherapy ◽  
2000 ◽  
Vol 46 (4) ◽  
pp. 235-244 ◽  
Author(s):  
Alfonso-Javier Carrillo-Muñoz ◽  
Guillermo Quindós ◽  
Cristina Tur ◽  
Maite Ruesga ◽  
Rocío Alonso ◽  
...  
Keyword(s):  
Antifungal Activity ◽  
Amphotericin B ◽  
Lipid Complex ◽  
Amphotericin B Lipid Complex ◽  
In Vitro Antifungal Activity

scholarly journals Carrier effects on biological activity of amphotericin B.

1996 ◽  
Vol 9 (4) ◽  
pp. 512-531 ◽  
Author(s):  
J Brajtburg ◽  
J Bolard
Keyword(s):  
Amphotericin B ◽  
Mammalian Cells ◽  
Fungal Infections ◽  
Therapeutic Index ◽  
Fungal Cell ◽  
Drug Of Choice ◽  
Higher Doses ◽  
Lipid Formulations

Amphotericin B (AmB), the drug of choice for the treatment of most systemic fungal infections, is marketed under the trademark Fungizone, as an AmB-deoxycholate complex suitable for intravenous administration. The association between AmB and deoxycholate is relatively weak; therefore, dissociation occurs in the blood. The drug itself interacts with both mammalian and fungal cell membranes to damage cells, but the greater susceptibility of fungal cells to its effects forms the basis for its clinical usefulness. The ability of the drug to form stable complexes with lipids has allowed the development of new formulations of AmB based on this property. Several lipid-based formulations of the drug which are more selective in damaging fungal or parasitic cells than mammalian cells and some of which also have a better therapeutic index than Fungizone have been developed. In vitro investigations have led to the conclusion that the increase in selectivity observed is due to the selective transfer of AmB from lipid complexes to fungal cells or to the higher thermodynamic stability of lipid formulations. Association with lipids modulates AmB binding to lipoproteins in vivo, thus influencing tissue distribution and toxicity. For example, lipid complexes of AmB can be internalized by macrophages, and the macrophages then serve as a reservoir for the drug. Furthermore, stable AmB-lipid complexes are much less toxic to the host than Fungizone and can therefore be administered in higher doses. Experimentally, the efficacy of AmB-lipid formulations compared with Fungizone depends on the animal model used. Improved therapeutic indices for AmB-lipid formations have been demonstrated in clinical trials, but the definitive trials leading to the selection of an optimal formulation and therapeutic regimen have not been done.

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