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Stott KE, Ahmadu A, Kajanga C, Moyo M, Gondwe E, Chimang’anga W, Chasweka M, Unsworth J, Jimenez-Valverde A, Jagota B, Shah RV, Lawrence DS, Lalloo DG, Harrison T, Jarvis JN, Hope W, Mwandumba HC. Population pharmacokinetics and CSF penetration of flucytosine in adults with HIV-associated cryptococcal meningoencephalitis. J Antimicrob Chemother 2023; 78:1015-1022. [PMID: 36857467 PMCID: PMC10068416 DOI: 10.1093/jac/dkad038] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 01/31/2023] [Indexed: 03/03/2023] Open
Abstract
BACKGROUND There are limited data describing clinical flucytosine pharmacokinetics (PK). The variability of flucytosine partitioning into the CNS is not known. We described the interindividual variability in flucytosine PK in patients with HIV-associated cryptococcal meningoencephalitis. In addition, we quantified the extent and variability of CSF partitioning of flucytosine. METHODS A PK study was conducted in 64 patients with confirmed HIV-associated cryptococcal meningoencephalitis in Blantyre, Malawi. A four-compartment PK model was developed, and Monte Carlo simulations were performed with flucytosine administered at different doses and in different schedules. RESULTS The estimated mean apparent volume of the central compartment was 17.50 (SD 9.99) L; mean apparent clearance was 5.88 (SD 3.35) L/h; mean apparent volume of the CNS compartment was 41.73 (SD 13.66) L. From the Bayesian posterior estimates, AUC24 values at steady state (144-168 h) with doses of 25 mg/kg q6h were median (IQR) 890.38 (603.81-1213.70) mg.h/L in plasma and 595.66 (425.69-776.64) mg.h/L in CSF. The ratio of CSF:plasma AUC24 was 0.69 (IQR 0.58-0.82). CONCLUSIONS This study revealed significant interindividual variability in flucytosine PK in plasma and CSF in patients with HIV-associated cryptococcal meningoencephalitis. The population PK model is a first critical step for revised flucytosine regimens that maximize fungal killing and minimize toxicity and the emergence of resistance.
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Affiliation(s)
- Katharine E Stott
- Antimicrobial Pharmacodynamics and Therapeutics, Department of Molecular and Clinical Pharmacology, University of Liverpool, Liverpool, UK
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Ajisa Ahmadu
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Cheusisime Kajanga
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Melanie Moyo
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- Department of Medicine, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Ebbie Gondwe
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Wezzie Chimang’anga
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Madalitso Chasweka
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Jennifer Unsworth
- Antimicrobial Pharmacodynamics and Therapeutics, Department of Molecular and Clinical Pharmacology, University of Liverpool, Liverpool, UK
| | - Ana Jimenez-Valverde
- Antimicrobial Pharmacodynamics and Therapeutics, Department of Molecular and Clinical Pharmacology, University of Liverpool, Liverpool, UK
| | - Bhavana Jagota
- Antimicrobial Pharmacodynamics and Therapeutics, Department of Molecular and Clinical Pharmacology, University of Liverpool, Liverpool, UK
| | - Reya V Shah
- Institute for Infection and Immunity, St George’s University London, London, UK
| | - David S Lawrence
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana
| | | | - Tom Harrison
- Clinical Academic Group in Infection, St George’s University Hospitals NHS Foundation Trust, London, UK
- MRC Centre for Medical Mycology, University of Exeter, Exeter, UK
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Joseph N Jarvis
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana
| | - William Hope
- Antimicrobial Pharmacodynamics and Therapeutics, Department of Molecular and Clinical Pharmacology, University of Liverpool, Liverpool, UK
| | - Henry C Mwandumba
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- Department of Medicine, Kamuzu University of Health Sciences, Blantyre, Malawi
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
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2
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Blastomycosis: A Review of Mycological and Clinical Aspects. J Fungi (Basel) 2023; 9:jof9010117. [PMID: 36675937 PMCID: PMC9863754 DOI: 10.3390/jof9010117] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 01/18/2023] Open
Abstract
Blastomycosis is caused by a thermally dimorphic fungus that thrives in moist acidic soil. Blastomyces dermatitidis is the species responsible for most infections in North America and is especially common in areas around the Great Lakes, the St. Lawrence Seaway, and in several south-central and southeastern United States. Other Blastomyces species have more recently been discovered to cause disease in distinct geographic regions around the world. Infection almost always occurs following inhalation of conidia produced in the mold phase. Acute pulmonary infection ranges from asymptomatic to typical community-acquired pneumonia; more chronic forms of pulmonary infection can present as mass-like lesions or cavitary pneumonia. Infrequently, pulmonary infection can progress to acute respiratory distress syndrome that is associated with a high mortality rate. After initial pulmonary infection, hematogenous dissemination of the yeast form of Blastomyces is common. Most often this is manifested by cutaneous lesions, but osteoarticular, genitourinary, and central nervous system (CNS) involvement also occurs. The diagnosis of blastomycosis can be made by growth of the mold phase of Blastomyces spp. in culture or by histopathological identification of the distinctive features of the yeast form in tissues. Detection of cell wall antigens of Blastomyces in urine or serum provides a rapid method for a probable diagnosis of blastomycosis, but cross-reactivity with other endemic mycoses commonly occurs. Treatment of severe pulmonary or disseminated blastomycosis and CNS blastomycosis initially is with a lipid formulation of amphotericin B. After improvement, therapy can be changed to an oral azole, almost always itraconazole. With mild to moderate pulmonary or disseminated blastomycosis, oral itraconazole treatment is recommended.
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3
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Chen L, van Rhee KP, Wasmann RE, Krekels EHJ, Wiezer MJ, van Dongen EPA, Verweij PE, van der Linden PD, Brüggemann RJ, Knibbe CAJ. Total bodyweight and sex both drive pharmacokinetic variability of fluconazole in obese adults. J Antimicrob Chemother 2022; 77:2217-2226. [PMID: 35613035 DOI: 10.1093/jac/dkac160] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 04/18/2022] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Fluconazole is commonly used to treat or prevent fungal infections. It is typically used orally but in critical situations, IV administration is needed. Obesity may influence the pharmacokinetics and therapeutic efficacy of a drug. In this study, we aim to assess the impact of obesity on fluconazole pharmacokinetics given orally or IV to guide dose adjustments for the obese population. METHODS We performed a prospective pharmacokinetic study with intensive sampling in obese subjects undergoing bariatric surgery (n = 17, BMI ≥ 35 kg/m2) and non-obese healthy controls (n = 8, 18.5 ≤ BMI < 30.0 kg/m2). Participants received a semi-simultaneous oral dose of 400 mg fluconazole capsules, followed after 2 h by 400 mg IV. Population pharmacokinetic modelling and simulation were performed using NONMEM 7.3. RESULTS A total of 421 fluconazole concentrations in 25 participants (total bodyweight 61.0-174 kg) until 48 h after dosing were obtained. An estimated bioavailability of 87.5% was found for both obese and non-obese subjects, with a 95% distribution interval of 43.9%-98.4%. With increasing total bodyweight, both higher CL and Vd were found. Sex also significantly impacted Vd, being 27% larger in male compared with female participants. CONCLUSIONS In our population of obese but otherwise healthy individuals, obesity clearly alters the pharmacokinetics of fluconazole, which puts severely obese adults, particularly if male, at risk of suboptimal exposure, for which adjusted doses are proposed.
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Affiliation(s)
- Lu Chen
- Division of Systems Pharmacology and Pharmacy, Leiden Academic Centre of Drug Research, Leiden University, Leiden, The Netherlands
| | - Koen P van Rhee
- Division of Systems Pharmacology and Pharmacy, Leiden Academic Centre of Drug Research, Leiden University, Leiden, The Netherlands.,Department of Clinical Pharmacy, Tergooi Medical Centre, Hilversum, The Netherlands
| | - Roeland E Wasmann
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Elke H J Krekels
- Division of Systems Pharmacology and Pharmacy, Leiden Academic Centre of Drug Research, Leiden University, Leiden, The Netherlands
| | - Marinus J Wiezer
- Department of Surgery, St. Antonius Hospital, Nieuwegein, The Netherlands
| | - Eric P A van Dongen
- Department of Anesthesiology, St. Antonius Hospital, Nieuwegein, The Netherlands
| | - Paul E Verweij
- Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, The Netherlands.,Radboudumc Center for Infectious Diseases and Center of Expertise in Mycology Radboudumc/CWZ, Nijmegen, The Netherlands
| | | | - Roger J Brüggemann
- Radboudumc Center for Infectious Diseases and Center of Expertise in Mycology Radboudumc/CWZ, Nijmegen, The Netherlands.,Department of Pharmacy, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Catherijne A J Knibbe
- Division of Systems Pharmacology and Pharmacy, Leiden Academic Centre of Drug Research, Leiden University, Leiden, The Netherlands.,Department of Clinical Pharmacy, St. Antonius Hospital, Nieuwegein, The Netherlands
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4
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Chen CH, Li H, Chen HM, Chen YM, Chang YJ, Lin PY, Hsu CW, Tseng PT, Lin KH, Tu YK. Efficacy of induction regimens for cryptococcal meningitis in HIV-infected adults: a systematic review and network meta-analysis. Sci Rep 2021; 11:8565. [PMID: 33883566 PMCID: PMC8060388 DOI: 10.1038/s41598-021-87726-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 04/01/2021] [Indexed: 11/09/2022] Open
Abstract
Cryptococcal meningitis (CM) is the most fatal adult meningitis in patients with human immunodeficiency virus (HIV). There is no conclusive evidence for the superiority of 1-week amphotericin B deoxycholate (AmphB) + flucytosine (5-FC) regimen over other antifungals in the management of HIV patients with CM (HIV-CM patients). We aimed to evaluate the differences in efficacy and tolerability of different antifungal agents in HIV-CM patients by conducting a current network meta-analysis NMA. Overall, 19 randomized controlled trials were included with 2642 participants. A regimen indicated a possibly lower early mortality rate, namely, AmphB + 5-FC + Azole (OR = 1.1E-12, 95% CIs = 1.3E-41 to 0.06) comparing to AmphB + 5-FC. The current NMA provides evidence that AmphB + 5-FC + Azole are superior to all the investigated treatments for induction regimen in HIV-CM patients.
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Affiliation(s)
- Chang-Hua Chen
- Division of Infectious Diseases, Department of Internal Medicine, Changhua Christian Hospital, Changhua, Taiwan
- Center for Infection Prevention and Control, Changhua Christian Hospital, Changhua, 500, Taiwan
- National Chung Hsing University, Taichung, Taiwan
- Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Hua Li
- Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan
| | - Hsien-Meng Chen
- Division of Infectious Diseases, Department of Internal Medicine, Changhua Christian Hospital, Changhua, Taiwan
| | - Yu-Min Chen
- Department of Pharmacy, Changhua Christian Hospital, Changhua, Taiwan
| | - Yu-Jun Chang
- Epidemiology and Biostatistics Center, Changhua Christian Hospital, Changhua, Taiwan
| | - Pao-Yen Lin
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
- Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Chih-Wei Hsu
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
- Department of Computer Science and Information Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Ping-Tao Tseng
- WinShine Clinics in Specialty of Psychiatry, Kaohsiung City, Taiwan
| | - Kai-Huang Lin
- Division of Critical Care Medicine, Department of Internal Medicine, Changhua Christian Hospital, Changhua, Taiwan
| | - Yu-Kang Tu
- Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.
- Department of Dentistry, National Taiwan University Hospital, Taipei, Taiwan.
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5
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Wirth F, Ishida K. Antifungal drugs: An updated review of central nervous system pharmacokinetics. Mycoses 2020; 63:1047-1059. [PMID: 32772402 DOI: 10.1111/myc.13157] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/23/2020] [Accepted: 08/02/2020] [Indexed: 01/06/2023]
Abstract
Invasive fungal infections (IFIs) in the central nervous system (CNS) are particularly hard to treat and are associated with high morbidity and mortality rates. Four chemical classes of systemic antifungal agents are used for the treatment of IFIs (eg meningitis), including polyenes, triazoles, pyrimidine analogues and echinocandins. This review will address all of these classes and discuss their penetration and accumulation in the CNS. Treatment of fungal meningitis is based on the antifungal that shows good penetration and accumulation in the CNS. Pharmacokinetic data concerning the entry of antifungal agents into the intracranial compartments are faulty. This review will provide an overview of the ability of systemic antifungals to penetrate the CNS, based on previously published drug physicochemical properties and pharmacokinetic data, for evaluation of the most promising antifungal drugs for the treatment of fungal CNS infections. The studies selected and discussed in this review are from 1990 to 2019.
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Affiliation(s)
- Fernanda Wirth
- Laboratory of Antifungal Chemotherapy, Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Kelly Ishida
- Laboratory of Antifungal Chemotherapy, Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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6
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Implications of Evolving and Emerging Pharmacokinetic-Pharmacodynamic Research for Triazoles and Echinocandins. CURRENT FUNGAL INFECTION REPORTS 2020. [DOI: 10.1007/s12281-020-00391-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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7
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Hope W, Stone NRH, Johnson A, McEntee L, Farrington N, Santoro-Castelazo A, Liu X, Lucaci A, Hughes M, Oliver JD, Giamberardino C, Mfinanga S, Harrison TS, Perfect JR, Bicanic T. Fluconazole Monotherapy Is a Suboptimal Option for Initial Treatment of Cryptococcal Meningitis Because of Emergence of Resistance. mBio 2019; 10:e02575-19. [PMID: 31796539 PMCID: PMC6890991 DOI: 10.1128/mbio.02575-19] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Accepted: 10/23/2019] [Indexed: 12/20/2022] Open
Abstract
Cryptococcal meningitis is a lethal disease with few therapeutic options. Induction therapy with fluconazole has been consistently demonstrated to be associated with suboptimal microbiological and clinical outcomes. Exposure to fluconazole causes dynamic changes in antifungal susceptibility, which are associated with the development of aneuploidy. The implications of this phenomenon for pharmacodynamics of fluconazole for cryptococcal meningitis are poorly understood. The pharmacodynamics of fluconazole were studied using a hollow-fiber infection model (HFIM) and a well-characterized murine model of cryptococcal meningoencephalitis. The relationship between drug exposure and both antifungal killing and the emergence of resistance was quantified. The same relationships were further evaluated in a recently described group of patients with cryptococcal meningitis undergoing induction therapy with fluconazole at 800 to 1,200 mg/day. The pattern of emergence of fluconazole resistance followed an "inverted U." Resistance amplification was maximal and suppressed at ratios of the area under the concentration-time curve for the free, unbound fraction of the drug to the MIC (fAUC:MIC) of 34.5 to 138 and 305.6, respectively. Emergence of resistance was observed in vivo with an fAUC:MIC of 231.4. Aneuploidy with duplication of chromosome 1 was demonstrated to be the underlying mechanism in both experimental models. The pharmacokinetic (PK)-pharmacodynamic model accurately described the PK, antifungal killing, and emergence of resistance. Monte Carlo simulations from the clinical pharmacokinetic-pharmacodynamic model showed that only 12.8% of simulated patients receiving fluconazole at 1,200 mg/day achieved sterilization of the cerebrospinal fluid (CSF) after 2 weeks and that 83.4% had a persistent subpopulation that was resistant to fluconazole. Fluconazole is primarily ineffective due to the emergence of resistance. Treatment with 1,200 mg/day leads to the killing of a susceptible subpopulation but is compromised by the emergence of resistance.IMPORTANCE Cryptococcal meningitis is a lethal disease with few treatment options. The incidence remains high and intricately linked with the HIV/AIDS epidemic. In many parts of the world, fluconazole is the only agent that is available for the initial treatment of cryptococcal meningitis despite considerable evidence that it is associated with suboptimal microbiological and clinical outcomes. Fluconazole has a fungistatic mode of action: it predominantly inhibits growth rather than causing fungal killing. Our work shows that the pattern of fluconazole activity is caused by the emergence of resistance in Cryptococcus not detected by standard susceptibility tests, with chromosomal duplication/aneuploidy as the main mechanism. Resistance emergence is related to drug exposure and occurs with the use of clinically relevant regimens. Hence, fluconazole (and potentially other agents that target 14-alpha-demethylase) is compromised by an intrinsic property that limits its effectiveness. However, this resistance may be potentially overcome by dosage escalation or the use of combination therapy.
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Affiliation(s)
- William Hope
- Antimicrobial Pharmacodynamics and Therapeutics, University of Liverpool, Liverpool Health Partners, Liverpool, United Kingdom
- Royal Liverpool Broadgreen University Hospital Trust, Liverpool Health Partners, Liverpool, United Kingdom
| | - Neil R H Stone
- Antimicrobial Pharmacodynamics and Therapeutics, University of Liverpool, Liverpool Health Partners, Liverpool, United Kingdom
- Institute of Infection and Immunity, St. George's, University of London, London, United Kingdom
| | - Adam Johnson
- Antimicrobial Pharmacodynamics and Therapeutics, University of Liverpool, Liverpool Health Partners, Liverpool, United Kingdom
| | - Laura McEntee
- Antimicrobial Pharmacodynamics and Therapeutics, University of Liverpool, Liverpool Health Partners, Liverpool, United Kingdom
| | - Nicola Farrington
- Antimicrobial Pharmacodynamics and Therapeutics, University of Liverpool, Liverpool Health Partners, Liverpool, United Kingdom
| | - Anahi Santoro-Castelazo
- Antimicrobial Pharmacodynamics and Therapeutics, University of Liverpool, Liverpool Health Partners, Liverpool, United Kingdom
| | - Xuan Liu
- Centre for Genomics Research, University of Liverpool, Liverpool, United Kingdom
| | - Anita Lucaci
- Centre for Genomics Research, University of Liverpool, Liverpool, United Kingdom
| | - Margaret Hughes
- Centre for Genomics Research, University of Liverpool, Liverpool, United Kingdom
| | | | - Charles Giamberardino
- Division of Infectious Diseases and International Health, Duke University School of Medicine, Durham, North Carolina, USA
| | - Sayoki Mfinanga
- National Institute of Medical Research, Dar es Salaam, Tanzania
| | - Thomas S Harrison
- Institute of Infection and Immunity, St. George's, University of London, London, United Kingdom
| | - John R Perfect
- Division of Infectious Diseases and International Health, Duke University School of Medicine, Durham, North Carolina, USA
| | - Tihana Bicanic
- Institute of Infection and Immunity, St. George's, University of London, London, United Kingdom
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8
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Chesdachai S, Rajasingham R, Nicol MR, Meya DB, Bongomin F, Abassi M, Skipper C, Kwizera R, Rhein J, Boulware DR. Minimum Inhibitory Concentration Distribution of Fluconazole against Cryptococcus Species and the Fluconazole Exposure Prediction Model. Open Forum Infect Dis 2019; 6:5550889. [PMID: 31420668 PMCID: PMC6767974 DOI: 10.1093/ofid/ofz369] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Fluconazole is lifesaving for treatment and prevention of cryptococcosis; however, optimal dosing is unknown. Initial fluconazole doses of 100mg to 2000mg/day have been used. Prevalence of fluconazole non-susceptible Cryptococcus is increasing over time, risking the efficacy of long-established standard dosing. Based on current minimum inhibitory concentration (MIC) distribution, we modeled fluconazole concentration and area under the curve (AUC) relative to MIC to propose a rational fluconazole dosing strategy. METHODS First, we conducted a systematic review using MEDLINE database for reports of fluconazole MIC distribution against clinical Cryptococcus isolates. Second, we utilized fluconazole concentrations from 92 Ugandans who received fluconazole 800mg/day coupled with fluconazole's known pharmacokinetics to predict plasma fluconazole concentrations for doses ranging from 100mg to 2000mg via linear regression. Third, the fluconazole AUC above MIC ratio were calculated using Monte Carlo simulation and using the MIC distribution elucidated during the systemic review. RESULTS We summarized 21 studies with 11,049 clinical Cryptococcus isolates. MICs were normally distributed with geometric mean of 3.4 μg/mL, median (MIC50) of 4 μg/mL, and 90th percentile (MIC90) of 16 μg/mL. The median MIC50 trended upwards from 4 μg/mL in 2000-2012 to 8 μg/mL in 2014-2018. Predicted sub-therapeutic fluconazole concentrations (below MIC) would occur in 40% with 100mg, 21% with 200mg, and 9% with 400mg. AUC/MIC ratio >100 would occur in 53% for 400mg, 74% for 800mg, 83% for 1200mg, and 88% for 1600mg. CONCLUSIONS Currently recommended fluconazole doses may be inadequate for cryptococcosis. Further clinical studies are needed for rational fluconazole dose selection.
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Affiliation(s)
| | - Radha Rajasingham
- Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Melanie R Nicol
- College of Pharmacy, Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN, USA
| | - David B Meya
- Infectious Diseases Institute, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Felix Bongomin
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Gulu University, Gulu, Uganda
| | - Mahsa Abassi
- Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Caleb Skipper
- Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Richard Kwizera
- Infectious Diseases Institute, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Joshua Rhein
- Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - David R Boulware
- Department of Medicine, University of Minnesota, Minneapolis, MN, USA
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9
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Gerhart JG, Watt KM, Edginton A, Wade KC, Salerno SN, Benjamin DK, Smith PB, Hornik CP, Cohen-Wolkowiez M, Duara S, Ross A, Shattuck K, Stewart DL, Neu N, Gonzalez D. Physiologically-Based Pharmacokinetic Modeling of Fluconazole Using Plasma and Cerebrospinal Fluid Samples From Preterm and Term Infants. CPT-PHARMACOMETRICS & SYSTEMS PHARMACOLOGY 2019; 8:500-510. [PMID: 31087536 PMCID: PMC6656941 DOI: 10.1002/psp4.12414] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 04/02/2019] [Indexed: 12/16/2022]
Abstract
Fluconazole is used to treat hematogenous Candida meningoencephalitis in preterm and term infants. To characterize plasma and central nervous system exposure, an adult fluconazole physiologically‐based pharmacokinetic (PBPK) model was scaled to infants, accounting for age dependencies in glomerular filtration and metabolism. The model was optimized using 760 plasma samples from 166 infants (median postmenstrual age (range) 28 weeks (24–50)) and 27 cerebrospinal fluid (CSF) samples from 22 infants (postmenstrual age 28 weeks (24–33)). Simulations evaluated achievement of the surrogate efficacy target of area under the unbound concentration‐time curve ≥ 400 mg • hour/L over the dosing interval in plasma and CSF using dosing guidelines. Average fold error of predicted concentrations was 0.73 and 1.14 for plasma and CSF, respectively. Target attainment in plasma and CSF was reached faster after incorporating a loading dose of 25 mg/kg. PBPK modeling can be useful in exploring CNS kinetics of drugs in children.
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Affiliation(s)
- Jacqueline G Gerhart
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Kevin M Watt
- Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Andrea Edginton
- School of Pharmacy, University of Waterloo, Waterloo, Ontario, Canada
| | - Kelly C Wade
- Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Sara N Salerno
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Daniel K Benjamin
- Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - P Brian Smith
- Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Christoph P Hornik
- Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Michael Cohen-Wolkowiez
- Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Shahnaz Duara
- Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Ashley Ross
- University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Karen Shattuck
- Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas, USA
| | - Dan L Stewart
- Department of Pediatrics, University of Louisville, Louisville, Kentucky, USA
| | - Natalie Neu
- Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - Daniel Gonzalez
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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