Safety, Tolerability, and Pharmacokinetics of Liposomal Amphotericin B in Immunocompromised Pediatric Patients

ABSTRACT The safety, tolerability, and pharmacokinetics of the liposomal formulation of amphotericin B (L-AMB) were evaluated in 40 immunocompromised children and adolescents. The protocol was an open-label, sequential-dose-escalation, multidose pharmacokinetic study with 10 to 13 patients in each of the four dosage cohorts. Each cohort received daily dosages of 2.5, 5.0, 7.5, or 10 mg of amphotericin B in the form of L-AMB per kg of body weight. Neutropenic patients between the ages of 1 and 17 years were enrolled to receive empirical antifungal therapy or treatment of documented invasive fungal infections. The pharmacokinetic parameters of L-AMB were measured as those of amphotericin B by high-performance liquid chromatography and calculated by noncompartmental methods. There were nine adverse-event-related discontinuations, four of which were related to infusions. Infusion-related side effects occurred for 63 (11%) of 565 infusions, with 5 patients experiencing acute infusion-related reactions (7.5- and 10-mg/kg dosage levels). Serum creatinine levels increased from 0.45 ± 0.04 mg/dl to 0.63 ± 0.06 mg/dl in the overall population (P = 0.003), with significant increases in dosage cohorts receiving 5.0 and 10 mg/kg/day. At the higher dosage level of 10 mg/kg, there was a trend toward greater hypokalemia and vomiting. The area under the concentration-time curve from 0 to 24 h (AUC0–24) values for L-AMB on day 1 increased from 54.7 ± 32.9 to 430 ± 566 μg · h/ml in patients receiving 2.5 and 10.0 mg/kg/day, respectively. These findings demonstrate that L-AMB can be administered to pediatric patients at dosages similar to those for adults and that azotemia may develop, especially in those receiving ≥5.0 mg/kg/day.

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Safety, Tolerance, and Pharmacokinetics of a Small Unilamellar Liposomal Formulation of Amphotericin B (AmBisome) in Neutropenic Patients

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.42.9.2391 ◽

1998 ◽

Vol 42 (9) ◽

pp. 2391-2398 ◽

Cited By ~ 128

Author(s):

Thomas J. Walsh ◽

Vijay Yeldandi ◽

Maureen McEvoy ◽

Corina Gonzalez ◽

Stephen Chanock ◽

...

Keyword(s):

Amphotericin B ◽

Antifungal Therapy ◽

High Performance ◽

Fungal Infections ◽

Empirical Therapy ◽

Liposomal Formulation ◽

Pharmacokinetic Parameters ◽

Open Label ◽

Empirical Antifungal Therapy ◽

Neutropenic Patients

ABSTRACT The safety, tolerance, and pharmacokinetics of a small unilamellar liposomal formulation of amphotericin B (AmBisome) administered for empirical antifungal therapy were evaluated for 36 persistently febrile neutropenic adults receiving cancer chemotherapy and bone marrow transplantation. The protocol was an open-label, sequential-dose-escalation, multidose pharmacokinetic study which enrolled a total of 8 to 12 patients in each of the four dosage cohorts. Each cohort received daily doses of either 1.0, 2.5, 5.0, or 7.5 mg of amphotericin B in the form of AmBisome/kg of body weight. The study population consisted of patients between the ages of 13 and 80 years with neutropenia (absolute neutrophil count, <500/mm3) who were eligible to receive empirical antifungal therapy. Patients were monitored for safety and tolerance by frequent laboratory examinations and the monitoring of infusion-related reactions. Efficacy was assessed by monitoring for the development of invasive fungal infection. The pharmacokinetic parameters of AmBisome were measured as those of amphotericin B by high-performance liquid chromatography. Noncompartmental methods were used to calculate pharmacokinetic parameters. AmBisome administered as a 1-h infusion in this population was well tolerated and was seldom associated with infusion-related toxicity. Infusion-related side effects occurred in 15 (5%) of all 331 infusions, and only two patients (5%) required premedication. Serum creatinine, potassium, and magnesium levels were not significantly changed from baseline in any of the dosage cohorts, and there was no net increase in serum transaminase levels. AmBisome followed a nonlinear dosage relationship that was consistent with reticuloendothelial uptake and redistribution. There were no breakthrough fungal infections during empirical therapy with AmBisome. AmBisome administered to febrile neutropenic patients in this study was well tolerated, was seldom associated with infusion-related toxicity, was characterized by nonlinear saturation kinetics, and was effective in preventing breakthrough fungal infections.

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Voriconazole Pharmacokinetics and Safety in Immunocompromised Children Compared to Adult Patients

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01731-09 ◽

2010 ◽

Vol 54 (8) ◽

pp. 3225-3232 ◽

Cited By ~ 50

Author(s):

Claudia Michael ◽

Uta Bierbach ◽

Katrin Frenzel ◽

Thoralf Lange ◽

Nadezda Basara ◽

...

Keyword(s):

Pediatric Patients ◽

Fungal Infections ◽

Adult Patients ◽

European Medicines Agency ◽

Pharmacokinetic Parameters ◽

Time Curve ◽

Entire Study ◽

Interindividual Variations ◽

Concentration Time ◽

Days Of Therapy

ABSTRACT The aim of this study was to investigate the pharmacokinetics and safety of voriconazole after intravenous (i.v.) administration in immunocompromised children (2 to 11 years old) and adults (20 to 60 years old) who required treatment for the prevention or therapy of systemic fungal infections. Nine pediatric patients were treated with a dose of 7 mg/kg i.v. every 12 h for a period of 10 days. Three children and 12 adults received two loading doses of 6 mg/kg i.v. every 12 h, followed by a maintenance dose of 5 mg/kg (children) or 4 mg/kg (adults) twice a day during the entire study period. Trough voriconazole levels in blood over 10 days of therapy and regular voriconazole levels in blood for up to 12 h postdose on day 3 were examined. Wide intra- and interindividual variations in plasma voriconazole levels were noted in each dose group and were most pronounced in the children receiving the 7-mg/kg dose. Five (56%) of them frequently had trough voriconazole levels in plasma below 1 μg/ml or above 6 μg/ml. The recommended dose of 7 mg/kg i.v. in children provides exposure (area under the concentration-time curve) comparable to that observed in adults receiving 4 mg/kg i.v. The children had significantly higher C max values; other pharmacokinetic parameters were not significantly different from those of adults. Voriconazole exhibits nonlinear pharmacokinetics in the majority of children. Voriconazole therapy was safe and well tolerated in pediatric and adult patients. The European Medicines Agency-approved i.v. dose of 7 mg/kg can be recommended for children aged 2 to <12 years.

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Herb-Drug Interaction betweenEchinacea purpureaand Darunavir-Ritonavir in HIV-Infected Patients

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01082-10 ◽

2010 ◽

Vol 55 (1) ◽

pp. 326-330 ◽

Cited By ~ 24

Author(s):

José Moltó ◽

Marta Valle ◽

Cristina Miranda ◽

Samandhy Cedeño ◽

Eugenia Negredo ◽

...

Keyword(s):

High Performance ◽

Geometric Mean ◽

Echinacea Purpurea ◽

The Body ◽

Pharmacokinetic Parameters ◽

Root Extract ◽

Open Label ◽

Fixed Sequence ◽

Time Curve ◽

Sequence Study

ABSTRACTThe aim of this open-label, fixed-sequence study was to investigate the potential ofEchinacea purpurea, a commonly used botanical supplement, to interact with the boosted protease inhibitor darunavir-ritonavir. Fifteen HIV-infected patients receiving antiretroviral therapy including darunavir-ritonavir (600/100 mg twice daily) for at least 4 weeks were included.E. purpurearoot extract capsules were added to the antiretroviral treatment (500 mg every 6 h) from days 1 to 14. Darunavir concentrations in plasma were determined by high-performance liquid chromatography immediately before and 1, 2, 4, 6, 8, 10, and 12 h after a morning dose of darunavir-ritonavir on days 0 (darunavir-ritonavir) and 14 (darunavir-ritonavir plus echinacea). Individual darunavir pharmacokinetic parameters were calculated by noncompartmental analysis and compared between days 0 and 14 with the geometric mean ratio (GMR) and its 90% confidence interval (CI). The median age was 49 (range, 43 to 67) years, and the body mass index was 24.2 (range, 18.7 to 27.5) kg/m2. Echinacea was well tolerated, and all participants completed the study. The GMR for darunavir coadministered with echinacea relative to that for darunavir alone was 0.84 (90% CI, 0.63-1.12) for the concentration at the end of the dosing interval, 0.90 (90% CI, 0.74-1.10) for the area under the concentration-time curve from 0 to 12 h, and 0.98 (90% CI, 0.82-1.16) for the maximum concentration. In summary, coadministration ofE. purpureawith darunavir-ritonavir was safe and well tolerated. Individual patients did show a decrease in darunavir concentrations, although this did not affect the overall darunavir or ritonavir pharmacokinetics. Although no dose adjustment is required, monitoring darunavir concentrations on an individual basis may give reassurance in this setting.

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Lack of Effect of Zafirlukast on the Pharmacokinetics of Azithromycin, Clarithromycin, and 14-Hydroxyclarithromycin in Healthy Volunteers

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.43.5.1152 ◽

1999 ◽

Vol 43 (5) ◽

pp. 1152-1155 ◽

Cited By ~ 16

Author(s):

Kevin W. Garey ◽

Charles A. Peloquin ◽

Paul G. Godo ◽

Anne N. Nafziger ◽

Guy W. Amsden

Keyword(s):

Steady State ◽

Healthy Subjects ◽

High Performance ◽

Pharmacokinetic Parameters ◽

Steady State Concentration ◽

Open Label ◽

Time Curve ◽

Data Analyses ◽

Concentration Time ◽

State Concentration

ABSTRACT This randomized, open-label, crossover study was conducted to investigate whether the coadministration of zafirlukast would affect the pharmacokinetics of azithromycin, clarithromycin, or 14-hydroxyclarithromycin (14-OHC). Twelve healthy subjects (six males and six females) received single 500-mg doses of azithromycin and clarithromycin with and without zafirlukast given to a steady-state concentration. Blood was collected prior to all macrolide doses and for 3 and 10 days after each clarithromycin and azithromycin dose, respectively. Serum was assayed for azithromycin, clarithromycin, and 14-OHC concentrations by validated high-performance liquid chromatography assay systems. Data analyses were done by noncompartmental and nonparametric methods. Analysis of the patients indicated that the addition of steady-state concentrations of zafirlukast did not significantly alter the pharmacokinetic parameters of or overall exposure (based on the area under the concentration-time curve) to azithromycin, clarithromycin, and 14-OHC. While zafirlukast is a known inhibitor of CYP3A4, it does not appear to exert a clinically or statistically significant pharmacokinetic effect on azithromycin, clarithromycin, or 14-OHC.

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Steady-State Pharmacokinetics of Abacavir in Plasma and Intracellular Carbovir Triphosphate following Administration of Abacavir at 600 Milligrams Once Daily and 300 Milligrams Twice Daily in Human Immunodeficiency Virus-Infected Subjects

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01000-08 ◽

2009 ◽

Vol 53 (4) ◽

pp. 1532-1538 ◽

Cited By ~ 32

Author(s):

Graeme Moyle ◽

Marta Boffito ◽

Carl Fletcher ◽

Chris Higgs ◽

Phillip E. Hay ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

High Performance ◽

Pharmacokinetic Parameters ◽

Virologic Suppression ◽

Open Label ◽

Time Curve ◽

Mixed Effect ◽

Once Daily ◽

Immunodeficiency Virus ◽

And Gender

ABSTRACT Abacavir (ABC) is administered either at 600 mg once daily (ABC 600 mg QD) or 300 mg twice daily (ABC 300 mg BID) in anti-human immunodeficiency virus (anti-HIV) combination therapy. Although ABC plasma pharmacokinetics following each regimen has been well defined, no study has directly compared the regimens with respect to pharmacokinetics of ABC's active intracellular anabolite, carbovir-triphosphate (CBV-TP). In an open-label, two-period, crossover study, 34 HIV-infected male and female subjects stabilized on antiretroviral regimens containing either ABC 600 mg QD or ABC 300 mg BID received their usual doses on days −1 and 1 and then switched regimens for days 2 to 11. Serial blood samples collected on days 1 and 11 were assayed for plasma ABC and intracellular CBV-TP concentrations using validated high-performance liquid chromatography-tandem mass spectrometry methods. Pharmacokinetic parameters were calculated using noncompartmental methods. Analysis of variance with a mixed-effect model was performed for treatment and gender comparisons. In 27 evaluable subjects, the regimens provided bioequivalent ABC daily areas under the concentration-time curve from 0 to 24 h (AUC0-24) and comparable CBV-TP concentrations at the end of the dosing interval (C τ). As expected, ABC QD resulted in 109% higher ABC maximum concentrations of drug in plasma (C max) than did ABC BID. ABC QD also resulted in 32% higher CBV-TP AUC0-24 and 99% higher CBV-TP C max than did ABC BID. Females had a 38% higher weight-adjusted ABC AUC0-24 and 81% higher weight-adjusted CBV-TP AUC0-24 than did males. Virologic suppression was maintained during regimen switch, and no tolerability differences between regimens were observed. In conclusion, this study showed that ABC 600 mg QD and ABC 300 mg BID regimens led to similar intracellular CBV-TP C τ values, thus providing pharmacokinetic support for the interchangeability of these two regimens. Women had higher intracellular CBV-TP exposure than did men.

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Empirical Antifungal Therapy for Patients with Neutropenia and Persitent Fever - Systematic Review and Meta-Analysis.

Blood ◽

10.1182/blood.v110.11.4961.4961 ◽

2007 ◽

Vol 110 (11) ◽

pp. 4961-4961

Author(s):

Elad Goldberg ◽

Anat Gafter-Gvili ◽

Mical Paul ◽

Eyal Robenshtok ◽

Liat Vidal ◽

...

Keyword(s):

Systematic Review ◽

Adverse Events ◽

Amphotericin B ◽

Antifungal Therapy ◽

Fungal Infections ◽

Meta Analysis ◽

Persistent Fever ◽

All Cause Mortality ◽

Empirical Antifungal Therapy ◽

Neutropenic Patients

Abstract Background: Opportunistic invasive fungal infections (IFIs) are a major concern in the management of immunocompromised patients with hematological malignancies. The practice of administering antifungal therapy to neutropenic patients with persistent fever has become a standard care. Conflicting data exists concerning the efficacy of empirical antifungal therapy. Objectives: This study aims to evaluate if empirical antifungal therapy reduces mortality and prevents invasive fungal infections (IFI). Methods: Systematic review and meta-analysis including randomized controlled trials (RCTs) comparing empirical antifungal treatment with placebo or no intervention (control), or another regimen, in neutropenic patients with persistent fever. The Cochrane Library, MEDLINE, conference proceedings and references were searched until 2007. Outcomes assessed were: All-cause mortality, documented IFI, and adverse events. Relative risks (RR) with 95% confidence intervals (CIs) were estimated and pooled. Results: Our search yielded 26 trials, 6 of which compared polyenes or azoles to control, and 20 compared between different regimens of polyenes, azoles or glucan synthesis inhibitors. Compared to control, there was no difference in all-cause mortality (RR 0.98; 95% CI 0.58–1.66, 5 trials, Fig.1). The risk for developing documented IFI was lower (RR 0.23; 95% CI 0.08–0.65, 4 trials, 4 events in the treatment group versus 18 in the control). When azoles (fluconazole, ketoconazole, itraconazole, voriconazole) were compared to polyenes (amphotericin B in 8 trials, liposomal ampho B in 1 trial) there was a trend in favor of azoles for decreased all-cause mortality (RR 0.89; 95% CI 0.73–1.09, 9 trials) and for decreased documented IFI (RR 0.70; 95% CI 0.47–1.04, 8 trials). Adverse events of any kind were less frequent in the azole group (RR 0.40; 95% CI 0.34–0.66, 5 trials), as were those which required discontinuation (RR 0.48; 95% CI 0.38–0.62, 7 trials). Conclusions: Our review demonstrates that empirical antifungal therapy does not reduce mortality. Although it reduces IFIs, data are based on a small number of trials and events. The use of amphotericin B as empirical antifungal therapy seems unwarranted since it appears to be less effective than azoles, with no mortality benefit and an increased rate of side effects. Future trials should pursue a pre-emptive approach using improved diagnostic tools (such as galactomannan testing, high resolution CT), to identify the patients for whom antifungal treatment is warranted. Figure Figure

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Herb-Drug Interaction between Echinacea purpurea and Etravirine in HIV-Infected Patients

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01205-12 ◽

2012 ◽

Vol 56 (10) ◽

pp. 5328-5331 ◽

Cited By ~ 14

Author(s):

José Moltó ◽

Marta Valle ◽

Cristina Miranda ◽

Samandhy Cedeño ◽

Eugenia Negredo ◽

...

Keyword(s):

High Performance ◽

Geometric Mean ◽

Echinacea Purpurea ◽

Interquartile Range ◽

Pharmacokinetic Parameters ◽

Root Extract ◽

Open Label ◽

Fixed Sequence ◽

Time Curve ◽

Content Type

ABSTRACTThe aim of this open-label, fixed-sequence study was to investigate the potential of the botanical supplementEchinacea purpureato interact with etravirine, a nonnucleoside reverse transcriptase inhibitor of HIV. Fifteen HIV-infected patients receiving antiretroviral therapy with etravirine (400 mg once daily) for at least 4 weeks were included.E. purpurearoot/extract-containing capsules were added to the antiretroviral treatment (500 mg every 8 h) for 14 days. Etravirine concentrations in plasma were determined by high-performance liquid chromatography immediately before and 1, 2, 4, 6, 8, 10, 12, and 24 h after a morning dose of etravirine on day 0 and etravirine plusE. purpureaon day 14. Individual etravirine pharmacokinetic parameters were calculated by noncompartmental analysis and compared between days 0 and 14 by means of the geometric mean ratio (GMR) and its 90% confidence interval (CI). The median age was 46 years (interquartile range, 41 to 50), and the median body weight was 76 kg (interquartile range, 68 to 92). Echinacea was well tolerated, and all participants completed the study. The GMR for etravirine coadministered withE. purpurearelative to etravirine alone was 1.07 (90% CI, 0.81 to 1.42) for the maximum concentration, 1.04 (90% CI, 0.79 to 1.38) for the area under the concentration-time curve from 0 to 24 h, and 1.04 (90% CI, 0.74 to 1.44) for the concentration at the end of the dosing interval. In conclusion, the coadministration ofE. purpureawith etravirine was safe and well tolerated in HIV-infected patients; our data suggest that no dose adjustment for etravirine is necessary.

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Determination of Appropriate Weight-Based Cutoffs for Empiric Cefazolin Dosing Using Data from a Phase 1 Pharmacokinetics and Safety Study of Cefazolin Administered for Surgical Prophylaxis in Pediatric Patients Aged 10 to 12 Years

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00082-15 ◽

2015 ◽

Vol 59 (7) ◽

pp. 4173-4180 ◽

Cited By ~ 5

Author(s):

Michael L. Schmitz ◽

Jeffrey L. Blumer ◽

Wes Cetnarowski ◽

Christopher M. Rubino

Keyword(s):

Pediatric Patients ◽

Phase 1 ◽

Pharmacokinetic Parameters ◽

Pharmacokinetic Data ◽

Time Data ◽

Surgical Prophylaxis ◽

Open Label ◽

Time Curve ◽

Concentration Time ◽

Few Data

ABSTRACTDespite over 40 years of worldwide usage, relatively few data have been published on the pharmacokinetics of cefazolin in pediatric surgical patients. The primary objectives of this study were to examine the pharmacokinetics and safety of cefazolin in children 10 to 12 years of age (inclusive) receiving 1 or 2 g of cefazolin, based on body weight. This multiple-center, open-label study enrolled pediatric patients electively scheduled for surgical procedures who required cefazolin as part of their routine clinical management. Patients weighing ≥25 to <50 kg received a 1-g dose, and patients weighing ≥50 to ≤85 kg received a 2-g dose. Postdose pharmacokinetic and safety assessments were conducted following drug administration. Cefazolin concentration-time data were analyzed by using both noncompartmental and population pharmacokinetics methods. Monte Carlo simulations were performed to identify appropriate weight-based cutoffs for the dosing of children aged 10 to 17 years of age. Twelve patients were enrolled in this study and provided the requisite pharmacokinetic data. In general, cefazolin was well tolerated. The mean cefazolin terminal elimination half-life, clearance, and area under the concentration-time curve from time zero to infinity in this population were 1.95 h, 0.804 ml/min/kg, and 607 mg · h/liter, respectively. Patients weighing 50 to 60 kg exhibited elevated cefazolin exposures. Observed pharmacokinetic parameters and simulation results indicated that a weight-based cutoff of 60 kg is predicted to provide cefazolin exposure consistent with that observed in normal, healthy adults at recommended doses for surgical prophylaxis. (This study has been registered at ClinicalTrials.gov under registration no. NCT01904357.)

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Effect of Milk Thistle on the Pharmacokinetics of Darunavir-Ritonavir in HIV-Infected Patients

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00025-12 ◽

2012 ◽

Vol 56 (6) ◽

pp. 2837-2841 ◽

Cited By ~ 16

Author(s):

José Moltó ◽

Marta Valle ◽

Cristina Miranda ◽

Samandhy Cedeño ◽

Eugenia Negredo ◽

...

Keyword(s):

High Performance ◽

Geometric Mean ◽

Interquartile Range ◽

Pharmacokinetic Parameters ◽

Milk Thistle ◽

Open Label ◽

Fixed Sequence ◽

Time Curve ◽

Sequence Study ◽

Inhibitor Combination

ABSTRACTThe aim of this open-label, fixed-sequence study was to investigate the potential of the botanical supplement milk thistle (silymarin) to interact with the boosted protease inhibitor combination darunavir-ritonavir. Fifteen HIV-infected patients receiving antiretroviral therapy with darunavir-ritonavir (600/100 mg twice daily) for at least 4 weeks were included. Silymarin (150 mg every 8 h) was added to the antiretroviral treatment from days 1 to 14. Darunavir concentrations in plasma were determined by high-performance liquid chromatography immediately before and 1, 2, 4, 6, 8, 10, and 12 h after a morning dose of darunavir-ritonavir on day 0 and darunavir-ritonavir plus silymarin on day 14. Individual darunavir pharmacokinetic parameters were calculated by noncompartmental analysis and compared between days 0 and 14 by means of the geometric mean ratio (GMR) and its 90% confidence interval (CI). The median age was 48 years (interquartile range, 44 to 50 years), and the median body weight was 70 kg (interquartile range, 65 to 84 kg). Silymarin was well tolerated, and all participants completed the study. The GMRs for darunavir coadministered with silymarin relative to darunavir alone were 0.86 (90% CI, 0.70 to 1.05) for the area under the concentration-time curve from 0 to 12 h, 0.83 (90% CI, 0.80 to 0.98) for the maximum concentration, and 0.94 (90% CI, 0.73 to 1.19) for the concentration at the end of the dosing interval. In summary, coadministration of silymarin with darunavir-ritonavir seems to be safe in HIV-infected patients; no dose adjustment for darunavir-ritonavir seems to be necessary.

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