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Abdelgawad N, Wasserman S, Abdelwahab MT, Davis A, Stek C, Wiesner L, Black J, Meintjes G, Wilkinson RJ, Denti P. Linezolid Population Pharmacokinetic Model in Plasma and Cerebrospinal Fluid Among Patients With Tuberculosis Meningitis. J Infect Dis 2024; 229:1200-1208. [PMID: 37740554 PMCID: PMC11011161 DOI: 10.1093/infdis/jiad413] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 09/09/2023] [Accepted: 09/20/2023] [Indexed: 09/24/2023] Open
Abstract
BACKGROUND Linezolid is evaluated in novel treatment regimens for tuberculous meningitis (TBM). Linezolid pharmacokinetics have not been characterized in this population, particularly in cerebrospinal fluid (CSF), as well as, following its co-administration with high-dose rifampicin. We aimed to characterize linezolid plasma and CSF pharmacokinetics in adults with TBM. METHODS In the LASER-TBM pharmacokinetic substudy, the intervention groups received high-dose rifampicin (35 mg/kg) plus 1200 mg/day of linezolid for 28 days, which was then reduced to 600 mg/day. Plasma sampling was done on day 3 (intensive) and day 28 (sparse). A lumbar CSF sample was obtained on both visits. RESULTS Thirty participants contributed 247 plasma and 28 CSF observations. Their median age and weight were 40 years (range, 27-56) and 58 kg (range, 30-96). Plasma pharmacokinetics was described by a 1-compartment model with first-order absorption and saturable elimination. Maximal clearance was 7.25 L/h, and the Michaelis-Menten constant was 27.2 mg/L. Rifampicin cotreatment duration did not affect linezolid pharmacokinetics. CSF-plasma partitioning correlated with CSF total protein up to 1.2 g/L, where the partition coefficient reached a maximal value of 37%. The plasma-CSF equilibration half-life was ∼3.5 hours. CONCLUSIONS Linezolid was readily detected in CSF despite high-dose rifampicin coadministration. These findings support continued clinical evaluation of linezolid plus high-dose rifampicin for the treatment of TBM in adults. Clinical Trials Registration. ClinicalTrials.gov (NCT03927313).
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Affiliation(s)
- Noha Abdelgawad
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, South Africa
| | - Sean Wasserman
- Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
- Institute for Infection and Immunity, St George's University of London, United Kingdom
| | - Mahmoud Tareq Abdelwahab
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, South Africa
| | - Angharad Davis
- Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
- The Francis Crick Institute, London, United Kingdom
- Faculty of Life Sciences, University College London, United Kingdom
| | - Cari Stek
- Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
| | - Lubbe Wiesner
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, South Africa
| | - John Black
- Department of Medicine, Walter Sisulu University, Mthatha, South Africa
| | - Graeme Meintjes
- Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
- Department of Medicine, University of Cape Town, South Africa
| | - Robert J Wilkinson
- Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, University of Cape Town, South Africa
- The Francis Crick Institute, London, United Kingdom
- Department of Infectious Diseases, Imperial College London, United Kingdom
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, South Africa
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Bock M, Van Hasselt JGC, Schwartz F, Wang H, Høiby N, Fuursted K, Ihlemann N, Gill S, Christiansen U, Bruun NE, Elming H, Povlsen JA, Køber L, Høfsten DE, Fosbøl EL, Pries-Heje MM, Christensen JJ, Rosenvinge FS, Torp-Pedersen C, Helweg-Larsen J, Tønder N, Iversen K, Bundgaard H, Moser C. Rifampicin reduces plasma concentration of linezolid in patients with infective endocarditis. J Antimicrob Chemother 2023; 78:2840-2848. [PMID: 37823408 DOI: 10.1093/jac/dkad316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 09/25/2023] [Indexed: 10/13/2023] Open
Abstract
BACKGROUND Linezolid in combination with rifampicin has been used in treatment of infective endocarditis especially for patients infected with staphylococci. OBJECTIVES Because rifampicin has been reported to reduce the plasma concentration of linezolid, the present study aimed to characterize the population pharmacokinetics of linezolid for the purpose of quantifying an effect of rifampicin cotreatment. In addition, the possibility of compensation by dosage adjustments was evaluated. PATIENTS AND METHODS Pharmacokinetic measurements were performed in 62 patients treated with linezolid for left-sided infective endocarditis in the Partial Oral Endocarditis Treatment (POET) trial. Fifteen patients were cotreated with rifampicin. A total of 437 linezolid plasma concentrations were obtained. The pharmacokinetic data were adequately described by a one-compartment model with first-order absorption and first-order elimination. RESULTS We demonstrated a substantial increase of linezolid clearance by 150% (95% CI: 78%-251%), when combined with rifampicin. The final model was evaluated by goodness-of-fit plots showing an acceptable fit, and a visual predictive check validated the model. Model-based dosing simulations showed that rifampicin cotreatment decreased the PTA of linezolid from 94.3% to 34.9% and from 52.7% to 3.5% for MICs of 2 mg/L and 4 mg/L, respectively. CONCLUSIONS A substantial interaction between linezolid and rifampicin was detected in patients with infective endocarditis, and the interaction was stronger than previously reported. Model-based simulations showed that increasing the linezolid dose might compensate without increasing the risk of adverse effects to the same degree.
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Affiliation(s)
- Magnus Bock
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Johan G C Van Hasselt
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Franziska Schwartz
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Hengzhuang Wang
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Niels Høiby
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Kurt Fuursted
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Nikolaj Ihlemann
- Department of Cardiology, Bispebjerg Hospital, Copenhagen, Denmark
| | - Sabine Gill
- Department of Cardiology, Odense University Hospital, Odense, Denmark
| | | | - Niels Eske Bruun
- Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
- Department of Cardiology, Zealand University Hospital, Roskilde, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Hanne Elming
- Department of Cardiology, Zealand University Hospital, Roskilde, Denmark
| | - Jonas A Povlsen
- Department of Cardiology, Aarhus University Hospital, Aarhus N, Denmark
| | - Lars Køber
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
- Department of Cardiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Dan E Høfsten
- Department of Cardiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Emil L Fosbøl
- Department of Cardiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Mia M Pries-Heje
- Department of Cardiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Jens Jørgen Christensen
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
- The Regional Department of Clinical Microbiology, Region Zealand, Slagelse, Denmark
| | - Flemming S Rosenvinge
- Department of Clinical Microbiology, Odense University Hospital, Odense, Denmark
- Research Unit of Clinical Microbiology, University of Southern Denmark, Odense, Denmark
| | - Christian Torp-Pedersen
- Department of Cardiology, Nordsjællands Hospital, Hillerød, Denmark
- Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Jannik Helweg-Larsen
- Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Niels Tønder
- Department of Cardiology, Nordsjællands Hospital, Hillerød, Denmark
| | - Kasper Iversen
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
- Department of Emergency Medicine, Copenhagen University Hospital, Herlev-Gentofte, Copenhagen, Denmark
| | - Henning Bundgaard
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
- Department of Cardiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Claus Moser
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
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Abdelgawad N, Wasserman S, Abdelwahab MT, Davis A, Stek C, Wiesner L, Black J, Meintjes G, Wilkinson RJ, Denti P. Linezolid population pharmacokinetic model in plasma and cerebrospinal fluid among patients with tuberculosis meningitis. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.04.06.23288230. [PMID: 37066148 PMCID: PMC10104225 DOI: 10.1101/2023.04.06.23288230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Background Linezolid is being evaluated in novel treatment regimens for tuberculous meningitis (TBM). The pharmacokinetics of linezolid have not been characterized in this population, particularly in cerebrospinal fluid (CSF) where exposures may be affected by changes in protein concentration and rifampicin co-administration. Methods This was a sub-study of a phase 2 clinical trial of intensified antibiotic therapy for adults with HIV-associated TBM. Participants in the intervention groups received high-dose rifampicin (35 mg/kg) plus linezolid 1200 mg daily for 28 days followed by 600 mg daily until day 56. Plasma was intensively sampled, and lumbar CSF was collected at a single timepoint in a randomly allocated sampling window, within 3 days after enrolment. Sparse plasma and CSF samples were also obtained on day 28. Linezolid concentrations were analyzed using non-linear mixed effects modelling. Results 30 participants contributed 247 plasma and 28 CSF linezolid observations. Plasma PK was best described by a one-compartment model with first-order absorption and saturable elimination. The typical value of maximal clearance was 7.25 L/h. Duration of rifampicin co-treatment (compared on day 3 versus day 28) did not affect linezolid pharmacokinetics. Partitioning between plasma and CSF correlated with CSF total protein concentration up to 1.2 g/L where the partition coefficient reached a maximal value of 37%. The equilibration half-life between plasma and CSF was estimated at ∼3.5 hours. Conclusion Linezolid was readily detected in CSF despite co-administration of the potent inducer rifampicin at high doses. These findings support continued clinical evaluation of linezolid plus high-dose rifampicin for the treatment of TBM in adults.
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Influence of Antibiotics on Functionality and Viability of Liver Cells In Vitro. Curr Issues Mol Biol 2022; 44:4639-4657. [PMID: 36286032 PMCID: PMC9600611 DOI: 10.3390/cimb44100317] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 09/17/2022] [Accepted: 09/22/2022] [Indexed: 11/22/2022] Open
Abstract
(1) Antibiotics are an important weapon in the fight against serious bacterial infections and are considered a common cause of drug-induced liver injury (DILI). The hepatotoxicity of many drugs, including antibiotics, is poorly analyzed in human in vitro models. (2) A standardized assay with a human hepatoma cell line was used to test the hepatotoxicity of various concentrations (Cmax, 5× Cmax, and 10× Cmax) of antibiotics. In an ICU, the most frequently prescribed antibiotics, ampicillin, cefepime, cefuroxime, levofloxacin, linezolid, meropenem, rifampicin, tigecycline, and vancomycin, were incubated with HepG2/C3A cells for 6 days. Cell viability (XTT assay, LDH release, and vitality), albumin synthesis, and cytochrome 1A2 activity were determined in cells. (3) In vitro, vancomycin, rifampicin, and tigecycline showed moderate hepatotoxic potential. The antibiotics ampicillin, cefepime, cefuroxime, levofloxacin, linezolid, and meropenem were associated with mild hepatotoxic reactions in test cells incubated with the testes Cmax concentration. Rifampicin and cefuroxime showed significantly negative effects on the viability of test cells. (4) Further in vitro studies and global pharmacovigilance reports should be conducted to reveal underlying mechanism of the hepatotoxic action of vancomycin, rifampicin, tigecycline, and cefuroxime, as well as the clinical relevance of these findings.
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5
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Lin B, Hu Y, Xu P, Xu T, Chen C, He L, Zhou M, Chen Z, Zhang C, Yu X, Fang L, Zhu J, Ji Y, Lin Q, Cao H, Dai Y, Lu X, Shi C, Li L, Wang C, Li X, Fang Q, Miao J, Zhu Z, Lin G, Zhan H, Lv S, Zhu Y, Cai X, Ying Y, Chen M, Xu Q, Zhang Y, Xu Y, Federico P, Jiang S, Dai H. Expert consensus statement on therapeutic drug monitoring and individualization of linezolid. Front Public Health 2022; 10:967311. [PMID: 36033811 PMCID: PMC9399604 DOI: 10.3389/fpubh.2022.967311] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Accepted: 07/19/2022] [Indexed: 01/24/2023] Open
Abstract
Linezolid is an oxazolidinone antibacterial drug, and its therapeutic drug monitoring and individualized treatment have been challenged since its approval. With the in-depth clinical research of linezolid, we have changed our attitude toward its therapeutic drug monitoring and our view of individualized treatment. On the basis of summarizing the existing clinical studies, and based on the practical experience of each expert in their respective professional fields, we have formed this expert consensus. Our team of specialists is a multidisciplinary team that includes pharmacotherapists, clinical pharmacology specialists, critical care medicine specialists, respiratory specialists, infectious disease specialists, emergency medicine specialists and more. We are committed to the safe and effective use of linezolid in patients in need, and the promotion of its therapeutic drug monitoring.
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Affiliation(s)
- Bin Lin
- Department of Pharmacy, Changxing People's Hospital, Changxing Branch, Second Affiliated Hospital of Zhejiang University School of Medicine, Huzhou, China,Key Laboratory of Intelligent Pharmacy and Individualized Therapy of Huzhou, Huzhou, China
| | - Yangmin Hu
- Department of Pharmacy, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Ping Xu
- Department of Pharmacy, Ningbo First Hospital, Ningbo, China
| | - Tao Xu
- Department of Pharmacy, Ningbo First Hospital, Ningbo, China
| | - Chunyan Chen
- Department of Pharmacy, Ningbo First Hospital, Ningbo, China
| | - Le He
- Department of Pharmacy, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Mi Zhou
- Department of Pharmacy, Children's Hospital of Soochow University, Suzhou, China
| | - Zhangzhang Chen
- Department of Pharmacy, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Chunhong Zhang
- Department of Pharmacy, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Xuben Yu
- Department of Pharmacy, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Luo Fang
- Department of Pharmacy, The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, China
| | - Junfeng Zhu
- Department of Pharmacy, The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, China
| | - Yanlan Ji
- Department of Pharmacy, Deqing People's Hospital, Huzhou, China
| | - Qun Lin
- Department of Pharmacy, Tiantai People's Hospital, Taizhou, China
| | - Hengbin Cao
- Department of Clinical Pharmacy, Huzhou Central Hospital, Huzhou, China
| | - Youqin Dai
- Department of Pharmacy, Hwa Mei Hospital, University of Chinese Academy of Sciences, Ningbo, China
| | - Xiaoyan Lu
- Department of Pharmacy, Hwa Mei Hospital, University of Chinese Academy of Sciences, Ningbo, China
| | - Changcheng Shi
- Department of Clinical Pharmacy, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Li Li
- Department of Pharmacy, Zhejiang Hospital, Hangzhou, China
| | - Changjiang Wang
- Department of Pharmacy, The Second Affiliated Hospital of Jiaxing University, Jiaxing, China
| | - Xumei Li
- Department of Pharmacy, The Second Affiliated Hospital of Jiaxing University, Jiaxing, China
| | - Qiongyan Fang
- Department of Pharmacy, Zhoushan Hospital, Zhoushan, China
| | - Jing Miao
- Department of Pharmacy, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Zhengyi Zhu
- Department of Pharmacy, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Guangyong Lin
- Department of Pharmacy, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Haichao Zhan
- Department of Clinical Pharmacy, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, China
| | - Shiwen Lv
- Department of Clinical Pharmacy, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, China
| | - Yalan Zhu
- Department of Clinical Pharmacy, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, China
| | - Xinjun Cai
- Department of Pharmacy, Affiliated Hangzhou Chest Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yin Ying
- Department of Pharmacy, Tongde Hospital of Zhejiang Province, Hangzhou, China
| | - Meng Chen
- Department of Pharmacy, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, China
| | - Qiong Xu
- Department of Pharmacy, Putuo Hospital, Zhoushan, China
| | - Yiwen Zhang
- Clinical Pharmacy Center, Department of Pharmacy, Zhejiang Provincial People's Hospital, Affiliated People's Hospital, Hangzhou Medical College, Hangzhou, China
| | - Yubin Xu
- Department of Pharmacy, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, China
| | - Pea Federico
- Department of Medical and Surgical Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy,SSD Clinical Pharmacology, Department for Integrated Infectious Risk Management, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - Saiping Jiang
- Department of Clinical Pharmacy, First Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China,Saiping Jiang
| | - Haibin Dai
- Key Laboratory of Intelligent Pharmacy and Individualized Therapy of Huzhou, Huzhou, China,Department of Pharmacy, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China,*Correspondence: Haibin Dai
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Linezolid Pharmacokinetics/Pharmacodynamics-Based Optimal Dosing for Multidrug-Resistant Tuberculosis. Int J Antimicrob Agents 2022; 59:106589. [DOI: 10.1016/j.ijantimicag.2022.106589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 02/03/2022] [Accepted: 04/03/2022] [Indexed: 11/05/2022]
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MDR Tuberculosis Treatment. Medicina (B Aires) 2022; 58:medicina58020188. [PMID: 35208510 PMCID: PMC8878254 DOI: 10.3390/medicina58020188] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/13/2022] [Accepted: 01/15/2022] [Indexed: 11/17/2022] Open
Abstract
Multidrug-resistant (MDR) tuberculosis (TB), resistant to isoniazid and rifampicin, continues to be one of the most important threats to controlling the TB epidemic. Over the last few years, there have been promising pharmacological advances in the paradigm of MDR TB treatment: new and repurposed drugs have shown excellent bactericidal and sterilizing activity against Mycobacterium tuberculosis and several all-oral short regimens to treat MDR TB have shown promising results. The purpose of this comprehensive review is to summarize the most important drugs currently used to treat MDR TB, the recommended regimens to treat MDR TB, and we also summarize new insights into the treatment of patients with MDR TB.
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8
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Linezolid Population Pharmacokinetics in South African Adults with Drug-Resistant Tuberculosis. Antimicrob Agents Chemother 2021; 65:e0138121. [PMID: 34543098 DOI: 10.1128/aac.01381-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Linezolid is widely used for drug-resistant tuberculosis (DR-TB) but has a narrow therapeutic index. To inform dose optimization, we aimed to characterize the population pharmacokinetics of linezolid in South African participants with DR-TB and explore the effect of covariates, including HIV coinfection, on drug exposure. Data were obtained from pharmacokinetic substudies in a randomized controlled trial and an observational cohort study, both of which enrolled adults with drug-resistant pulmonary tuberculosis. Participants underwent intensive and sparse plasma sampling. We analyzed linezolid concentration data using nonlinear mixed-effects modeling and performed simulations to estimate attainment of putative efficacy and toxicity targets. A total of 124 participants provided 444 plasma samples; 116 were on the standard daily dose of 600 mg, while 19 had dose reduction to 300 mg due to adverse events. Sixty-one participants were female, 71 were HIV-positive, and their median weight was 56 kg (interquartile range [IQR], 50 to 63). In the final model, typical values for clearance and central volume were 3.57 liters/h and 40.2 liters, respectively. HIV coinfection had no significant effect on linezolid exposure. Simulations showed that 600-mg dosing achieved the efficacy target (area under the concentration-time curve for the free, unbound fraction of the drug [[Formula: see text] at a MIC level of 0.5 mg/liter) with 96% probability but had 56% probability of exceeding safety target ([Formula: see text]. The 300-mg dose did not achieve adequate efficacy exposures. Our model characterized population pharmacokinetics of linezolid in South African patients with DR-TB and supports the 600-mg daily dose with safety monitoring.
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9
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Tietjen AK, Kroemer N, Cattaneo D, Baldelli S, Wicha SG. Population pharmacokinetics and target attainment analysis of linezolid in multidrug-resistant tuberculosis patients. Br J Clin Pharmacol 2021; 88:1835-1844. [PMID: 34622478 DOI: 10.1111/bcp.15102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 08/31/2021] [Accepted: 09/22/2021] [Indexed: 01/02/2023] Open
Abstract
AIM This study investigates the pharmacokinetic/pharmacodynamic (PK/PD) target attainment of linezolid in patients infected with multidrug-resistant (MDR) tuberculosis (TB). METHODS A pharmacometric model was developed including 244 timed linezolid concentration samples from 39 patients employing NONMEM 7.4. The probability of target attainment (PTA, PK/PD target: unbound (f) area-under-the-concentration-time-curve (AUC)/minimal inhibitory concentration (MIC) of 119) as well as a region-specific cumulative fraction of response (CFR) were estimated for different dosing regimens. RESULTS A one-compartment model with linear elimination with a clearance (CL) of 7.69 L/h (interindividual variability 34.1%), a volume of distribution (Vd) of 45.2 L and an absorption constant (KA) of 0.679 h-1 (interoccasion variability 143.7%) allometric scaled by weight best described the PK of linezolid. The PTA at an MIC of 0.5 mg/L was 55% or 97% if patients receiving 300 or 600 mg twice daily, respectively. CFRs varied greatly among populations and geographic regions. A desirable global CFR of ≥90% was achieved if linezolid was administered at a dose of 600 mg twice daily but not at a dose of 300 mg twice daily. CONCLUSION This study showed that a dose of 300 mg twice daily of linezolid might not be sufficient to treat MDR-TB patients from a PK/PD perspective. Thus, it might be recommendable to start with a higher dose of 600 mg twice daily to ensure PK/PD target attainment. Hereby, therapeutic drug monitoring and MIC determination should be performed to control PK/PD target attainment as linezolid shows high variability in its PK in the TB population.
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Affiliation(s)
- Anna K Tietjen
- Department of Clinical Pharmacy, Institute of Pharmacy, University of Hamburg, Hamburg, Germany.,University of Lübeck, Lübeck, Germany
| | - Niklas Kroemer
- Department of Clinical Pharmacy, Institute of Pharmacy, University of Hamburg, Hamburg, Germany
| | - Dario Cattaneo
- Unit of Clinical Pharmacology, Department of Laboratory Medicine, Luigi Sacco University Hospital, Milan, Italy
| | - Sara Baldelli
- Unit of Clinical Pharmacology, Department of Laboratory Medicine, Luigi Sacco University Hospital, Milan, Italy
| | - Sebastian G Wicha
- Department of Clinical Pharmacy, Institute of Pharmacy, University of Hamburg, Hamburg, Germany
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10
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Imperial MZ, Nedelman JR, Conradie F, Savic RM. Proposed linezolid dosing strategies to minimize adverse events for treatment of extensively drug-resistant tuberculosis. Clin Infect Dis 2021; 74:1736-1747. [PMID: 34604901 PMCID: PMC9155613 DOI: 10.1093/cid/ciab699] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND We evaluated clinical trial data (Nix-TB, NCT02333799) to provide data-driven dosing recommendations to potentially minimize linezolid toxicity in patients with extensively drug-resistant tuberculosis. METHODS Based on 104 participants, a pharmacokinetic model and toxicodynamic models for peripheral neuropathy, hemoglobin, and platelets were developed. Simulations compared safety outcomes for daily linezolid of 1200 and 600 mg, with and without dose adjustments for toxicity. Severe neuropathy was based on symptom scores from the Brief Peripheral Neuropathy Screen. Severe anemia and thrombocytopenia were defined as ≥grade 3 adverse events according to the Division of Microbiology and Infectious Disease Adult Toxicity table. RESULTS Predicted individual concentration-time profiles were a major predictor in all three toxicodynamic models. Simulations showed higher percentages of patients with severe neuropathy (median: 19% (90%CI: 17-22%) vs 5% (4-7%)) and severe anemia (15% (12-17%) vs 1% (0-2%)) between 1200 and 600 mg daily linezolid. No differences in severe thrombocytopenia were observed (median: <1% for both daily doses). Generally, neuropathy occurred after 3 to 6 months of treatment and, with protocol-specified management, reversed within 15 months after onset. Simulations indicated that a >10% decrease from pretreatment in hemoglobin level after 4 weeks of treatment would have maximum sensitivity (82%) and specificity (84%) for predicting severe anemia. Reducing dose from 1200 to 600 mg triggered by this marker may prevent 60% (90%CI: 45-72) of severe anemia. CONCLUSIONS Simple neuropathy symptom and hemoglobin monitoring may guide linezolid dosing to avoid toxicities, but prospective testing is needed to confirm benefit-to-risk ratio.
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Affiliation(s)
- Marjorie Z Imperial
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy, University of California, San Francisco, CA, USA
| | | | - Francesca Conradie
- Clinical HIV Research Unit, University of Witwatersrand, Johannesburg, South Africa
| | - Rada M Savic
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy, University of California, San Francisco, CA, USA
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11
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Nyang'wa BT, Kloprogge F, Moore DAJ, Bustinduy A, Motta I, Berry C, Davies GR. Population pharmacokinetics and pharmacodynamics of investigational regimens' drugs in the TB-PRACTECAL clinical trial (the PRACTECAL-PKPD study): a prospective nested study protocol in a randomised controlled trial. BMJ Open 2021; 11:e047185. [PMID: 34489274 PMCID: PMC8422304 DOI: 10.1136/bmjopen-2020-047185] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
INTRODUCTION Drug-resistant tuberculosis (TB) remains a global health threat, with little over 50% of patients successfully treated. Novel regimens like the ones being studied in the TB-PRACTECAL trial are urgently needed. Understanding anti-TB drug exposures could explain the success or failure of these trial regimens. We aim to study the relationship between the patients' exposure to anti-TB drugs in TB-PRACTECAL investigational regimens and their treatment outcomes. METHODS AND ANALYSIS Adults with multidrug-resistant TB randomised to investigational regimens in TB-PRACTECAL will be recruited to a nested pharmacokinetic-pharmacodynamic (PKPD) study. Venous blood samples will be collected at 0, 2 and 23 hours postdose on day 1 and 0, 6.5 and 23 hours postdose during week 8 to quantify drug concentrations in plasma. Trough samples will be collected during week 12, 16, 20 and 24 visits. Opportunistic samples will be collected during weeks 32 and 72. Drug concentrations will be quantified using liquid chromatography-tandem mass spectrometry. Sputum samples will be collected at baseline, monthly to week 24 and then every 2 months to week 108 for MICs and bacillary load quantification. Full blood count, urea and electrolytes, liver function tests, lipase, ECGs and ophthalmology examinations will be conducted at least monthly during treatment.PK and PKPD models will be developed for each drug with nonlinear mixed effects methods. Optimal dosing will be investigated using Monte-Carlo simulations. ETHICS AND DISSEMINATION The study has been approved by the Médecins sans Frontières (MSF) Ethics Review Board, the LSHTM Ethics Committee, the Belarus RSPCPT ethics committee and PharmaEthics and the University of Witwatersrand Human Research ethics committee in South Africa. Written informed consent will be obtained from all participants. The study results will be shared with public health authorities, presented at scientific conferences and published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER NCT04081077; Pre-results.
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Affiliation(s)
- Bern-Thomas Nyang'wa
- Manson Unit, Médecins Sans Frontières, London, UK
- Clinical research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Frank Kloprogge
- Institute for Global Health, University College London, London, UK
| | - David A J Moore
- Clinical research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Amaya Bustinduy
- Clinical research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Ilaria Motta
- Manson Unit, Médecins Sans Frontières, London, UK
| | | | - Geraint R Davies
- Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
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12
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Rao GG, Konicki R, Cattaneo D, Alffenaar JW, Marriott DJE, Neely M. Therapeutic Drug Monitoring Can Improve Linezolid Dosing Regimens in Current Clinical Practice: A Review of Linezolid Pharmacokinetics and Pharmacodynamics. Ther Drug Monit 2021; 42:83-92. [PMID: 31652190 DOI: 10.1097/ftd.0000000000000710] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Linezolid is an antibiotic used to treat infections caused by drug-resistant gram-positive organisms, including vancomycin-resistant Enterococcus faecium, multi-drug resistant Streptococcus pneumoniae, and methicillin-resistant Staphylococcus aureus. The adverse effects of linezolid can include thrombocytopenia and neuropathy, which are more prevalent with higher exposures and longer treatment durations. Although linezolid is traditionally administered at a standard 600 mg dose every 12 hours, the resulting exposure can vary greatly between patients and can lead to treatment failure or toxicity. The efficacy and toxicity of linezolid are determined by the exposure achieved in the patient; numerous clinical and population pharmacokinetics (popPK) studies have identified threshold measurements for both parameters. Several special populations with an increased need for linezolid dose adjustments have also been identified. Therapeutic Drug Monitoring (TDM) is a clinical strategy that assesses the response of an individual patient and helps adjust the dosing regimen to maximize efficacy while minimizing toxicity. Adaptive feedback control and model-informed precision dosing are additional strategies that use Bayesian algorithms and PK models to predict patient-specific drug exposure. TDM is a very useful tool for patient populations with sparse clinical data or known alterations in pharmacokinetics, including children, patients with renal insufficiency or those receiving renal replacement therapy, and patients taking co-medications known to interact with linezolid. As part of the clinical workflow, clinicians can use TDM with the thresholds summarized from the current literature to improve linezolid dosing for patients and maximize the probability of treatment success.
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Affiliation(s)
- Gauri G Rao
- UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina
| | - Robyn Konicki
- UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina
| | - Dario Cattaneo
- Unit of Clinical Pharmacology, Department of Laboratory Medicine, Luigi Sacco University Hospital, Milan, Italy
| | - Jan-Willem Alffenaar
- University of Sydney, Faculty of Medicine and Health, School of Pharmacy.,Westmead Hospital, Sydney, NSW, Australia.,Marie Bashir Institute of Infectious Diseases and Biosecurity, University of Sydney, Sydney, Australia
| | - Deborah J E Marriott
- Department of Clinical Microbiology and Infectious Diseases, St. Vincent's Hospital, Sydney, NSW, Australia
| | - Michael Neely
- Laboratory of Applied Pharmacokinetics and Bioinformatics, The Saban Research Institute, Children's Hospital Los Angeles; and.,Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, California
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13
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Pieterman ED, Keutzer L, van der Meijden A, van den Berg S, Wang H, Zimmerman MD, Simonsson USH, Bax HI, de Steenwinkel JEM. Superior efficacy of a bedaquiline, delamanid and linezolid combination regimen in a mouse-TB model. J Infect Dis 2021; 224:1039-1047. [PMID: 33502537 DOI: 10.1093/infdis/jiab043] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 01/21/2021] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND The treatment success rate of drug-resistant tuberculosis (DR-TB) is alarmingly low. Therefore, more effective and less complex regimens are urgently required. METHODS We compared the efficacy of an all oral DR-TB drug regimen consisting of bedaquiline (25 mg/kg), delamanid (2.5 mg/kg) and linezolid (100 mg/kg) (BDL) on the mycobacterial load in the lungs and spleen of TB infected mice during a treatment period of 24 weeks. This treatment was compared to the standard regimen of isoniazid, rifampicin, pyrazinamide and ethambutol (HRZE). Relapse was assessed 12 weeks post-treatment. Two logistic regression models were developed to compare the efficacy of both regimens. RESULTS Culture negativity in the lungs was achieved at 8 and 20 weeks of treatment with BDL and HRZE, respectively. After 14 weeks of treatment only one mouse relapsed in the BDL group, while in the HRZE group relapse was still observed at 24 weeks of treatment. Predictions from the final mathematical models showed that a 95% cure rate was reached after 20.5 and 28.5 weeks of treatment with BDL and HRZE, respectively. CONCLUSION The BDL regimen was observed to be more effective than HRZE and could be a valuable option for the treatment of DR-TB.
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Affiliation(s)
- Elise D Pieterman
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Lina Keutzer
- Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - Aart van der Meijden
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Sanne van den Berg
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Han Wang
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, USA
| | - Matthew D Zimmerman
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, USA
| | | | - Hannelore I Bax
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Internal Medicine, Section of Infectious Diseases, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Jurriaan E M de Steenwinkel
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, the Netherlands
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14
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Evaluation of Linezolid Pharmacokinetics in Critically Ill Obese Patients with Severe Skin and Soft Tissue Infections. Antimicrob Agents Chemother 2021; 65:AAC.01619-20. [PMID: 33257446 DOI: 10.1128/aac.01619-20] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 11/04/2020] [Indexed: 11/20/2022] Open
Abstract
Linezolid standard dosing is fixed at 600 mg every 12 h (q12h) for adults. Literature suggests critically ill, obese patients require higher doses. The study aim is 2-fold: (i) to describe linezolid pharmacokinetics (PK), and (ii) to evaluate if PK/pharmacodynamic (PD) target attainment is achieved with standard dosing in critically ill, obese patients with severe skin and soft tissue infections (SSTIs). Adult patients with a body mass index (BMI) of ≥30 kg/m2 and receiving intravenous (i.v.) linezolid from August 2018 to April 2019 were eligible for consent in this prospective study. Severe SSTIs were defined as necrotizing fasciitis, myonecrosis, or SSTI with sepsis syndrome. Four blood samples were collected at steady state at 1, 3, 5 h postinfusion and as a trough. Target attainment was defined as achieving area under the concentration-time curve from 0 to 24 h to MIC (AUC0-24h/MIC) of ≥100 h*mg/liter. Monte Carlo simulations were used to determine the probability of target attainment (PTA). Eleven patients were included in the study. The median BMI was 45.7 kg/m2, and median total body weight (TBW) was 136.0 kg. Seven patients received standard linezolid doses, and four received 600 mg q8h. A one-compartment model described linezolid PK. Based on AUC0-24h/MIC targets, for noncirrhotic patients at 140 kg, the PTA with standard linezolid doses was 100%, 98.8%, 34.1%, and 0% for MICs of 0.5, 1, 2, and 4 mg/liter, respectively. In conclusion, target attainment of ≥90% is not achieved with standard linezolid doses for noncirrhotic patients ≥140 kg with MICs of ≥2 mg/liter. This study adds to accumulating evidence that standard linezolid doses may not be adequate for all patients.
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15
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Developing New Drugs for Mycobacterium tuberculosis Therapy: What Information Do We Get from Preclinical Animal Models? Antimicrob Agents Chemother 2020; 64:AAC.01376-20. [PMID: 32958720 DOI: 10.1128/aac.01376-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/16/2020] [Indexed: 12/22/2022] Open
Abstract
Preclinical animal models of infection are employed to develop new agents but also to screen among molecules to rank them. There are often major differences between human pharmacokinetic (PK) profiles and those developed by animal models of infection, and these may lead to substantial differences in efficacy relative to that seen in humans. Linezolid is a repurposed agent employed to great effect for therapy of Mycobacterium tuberculosis In this study, we used the hollow-fiber infection model (HFIM) to evaluate the impact of different pharmacokinetic profiles of mice and nonhuman primates (NHP) versus humans on bacterial cell kill as well as resistance suppression. We examined both plasma and epithelial lining fluid (ELF) profiles. We examined simulated exposures equivalent to 600 mg and 900 mg daily of linezolid in humans. For both plasma and ELF exposures, the murine PK profile provided estimates of effect that were biased low relative to human and NHP PK profiles. Mathematical modeling identified a linkage between minimum concentrations (C min) and bacterial kill and peak concentrations (C peak) and resistance suppression, with the latter being supported by a prospective validation study. Finding new agents with novel mechanisms of action against M. tuberculosis is difficult. It would be a tragedy to discard a new agent because of a biased estimate of effect in a preclinical animal system. The HFIM provides a system to benchmark evaluation of new compounds in preclinical animal model systems against human PK effects (species scale-up estimates of PK), to safeguard against unwarranted rejection of promising new agents.
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16
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Population Pharmacokinetics of Linezolid in Tuberculosis Patients: Dosing Regimen Simulation and Target Attainment Analysis. Antimicrob Agents Chemother 2020; 64:AAC.01174-20. [PMID: 32778547 DOI: 10.1128/aac.01174-20] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/03/2020] [Indexed: 01/24/2023] Open
Abstract
The prolonged treatment duration for multidrug-resistant tuberculosis (MDR-TB) makes linezolid dosing difficult because of adverse effects associated with long-term use. We sought to find the optimal dosing regimen for linezolid across different MIC values. Pharmacokinetic (PK) data from TB patients were included from Brazil, Georgia, and two U.S. sites. Population PK modeling and simulation were performed. We used an fAUC (area under the unbound drug concentration-time curve)/MIC ratio of >119 as the PK/pharmacodynamic (PD) target and minimum (trough) concentrations of drug (C mins) of 2 and 7 mg/liter as thresholds for toxicity. The PK/PD breakpoint was defined as the highest MIC at which the probability of target attainment is >90%. A total of 104 patients with pulmonary TB were included, with a median age and weight of 37 years and 60 kg. Eighty-one percent had drug-resistant TB. The PK data were best described by a one-compartment model. The PK/PD breakpoint was 0.125 mg/liter for a total daily dose of 300 mg, while daily doses of 450 to 600 mg and 900 to 1,200 mg had PK/PD breakpoints of 0.25 and 0.50 mg/liter, respectively. The probability of achieving a C min of ≤2 mg/liter was higher when the dose was given at once than when dividing it into 2 doses. Linezolid at a daily dose of 300 mg may not be optimal. We predicted an excellent and comparable efficacy of linezolid using total daily doses of 900 and 1,200 mg for MICs of ≤0.5 mg/liter but with the potential for more toxicity than with 600 mg daily. The increase in C min was noticeable when the daily dose was divided and may incur greater toxicity.
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17
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Distribution of Linezolid in Tuberculosis Lesions in Patients with Spinal Multidrug-Resistant Tuberculosis. Antimicrob Agents Chemother 2020; 64:AAC.00450-20. [PMID: 32366717 DOI: 10.1128/aac.00450-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 04/28/2020] [Indexed: 01/15/2023] Open
Abstract
Linezolid has strong antimicrobial activity against the multidrug-resistant (MDR) strains of Mycobacterium tuberculosis Little is known about the distribution of linezolid in tuberculosis (TB) lesions in patients with MDR-TB. The aim of this study was to evaluate the distribution of linezolid in TB lesions in patients with spinal MDR-TB. Nine patients with spinal MDR-TB were enrolled prospectively from August 2019 to February 2020. The patients received a linezolid-containing anti-TB treatment regimen and needed surgery for the removal of TB lesions. During the operation, nine blood samples, eight diseased bone tissue samples, seven pus samples, and four granulation tissue samples were collected simultaneously and 2 h after the oral administration of 600 mg of linezolid. Linezolid concentrations in plasma, diseased bone tissue, pus, and granulation tissue samples were subjected to high-performance liquid chromatography-tandem mass spectrometry. At sample collection, the mean concentrations of linezolid in plasma, diseased bone tissue, pus, and granulation tissue samples of the nine patients were 11.14 ± 5.82, 5.94 ± 4.27, 11.09 ± 4.58, and 14.08 ± 10.61 mg/liter, respectively. The mean ratios of linezolid concentration in diseased bone/plasma, pus/plasma, and granulation/plasma were 53.84%, 91.69%, and 103.57%, respectively. The mean ratios of linezolid concentration in pus/plasma and granulation/plasma were higher than those in diseased bone/plasma, and the difference was statistically significant (t = -2.810, P = 0.015; t = -4.901, P = 0.001). In conclusion, linezolid had different concentration distributions in different types of TB-infected tissues in patients with spinal MDR-TB.
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18
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Linezolid Concentrations in Plasma and Subcutaneous Tissue are Reduced in Obese Patients, Resulting in a Higher Risk of Underdosing in Critically Ill Patients: A Controlled Clinical Pharmacokinetic Study. J Clin Med 2020; 9:jcm9041067. [PMID: 32283731 PMCID: PMC7230366 DOI: 10.3390/jcm9041067] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 03/27/2020] [Accepted: 04/07/2020] [Indexed: 01/11/2023] Open
Abstract
Background: Linezolid is used for the treatment of soft tissue infections in critically ill patients. However, data for characterizing the pharmacokinetics (PK) and assessing whether effective concentrations are reached at the target site are lacking. We hypothesized that current dosing regimens do not lead to effective concentrations in the plasma and interstitial fluid (ISF) of subcutaneous tissue in obese patients. Methods: As a controlled clinical model, critically ill obese and non-obese patients undergoing intra-abdominal surgery received 600 mg linezolid as a single infusion. Concentrations in the plasma and microdialysate from the ISF of subcutaneous tissue were determined up to 8 h after dosing. Pharmacokinetic analysis was performed by non-compartmental methods. As a therapeutic target, we used fAUC/MIC > 80. Results: Fifteen obese (BMI: 48.7 ± 11.2 kg/m2) and 15 non-obese (23.9 ± 2.1 kg/m2) patients were analyzed. AUC0–8 in ISF decreased by −1.69 mg*h/L (95% CI: −2.59 to −0.79, p < 0.001) for every 10 kg increase in weight. PK in obese patients were characterized by lower maximal plasma concentrations (median 3.8 vs. 8.3 mg/L, p < 0.001) and a higher volume of distribution (41.0 vs. 30.8 L, p < 0.001), and the therapeutic target was not reached for MIC ≥ 1 mg/L in ISF and ≥ 2 mg/L in plasma. Conclusions: Increasing the weight led to a decrease of linezolid concentrations in the plasma and subcutaneous tissue. The current dosing regimen does not seem to produce sufficient concentrations to kill bacteria with MIC ≥ 2 mg/L, especially as empirical antimicrobial therapy in critically ill obese patients.
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19
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Fourteen-Day Bactericidal Activity, Safety, and Pharmacokinetics of Linezolid in Adults with Drug-Sensitive Pulmonary Tuberculosis. Antimicrob Agents Chemother 2020; 64:AAC.02012-19. [PMID: 31988102 PMCID: PMC7179319 DOI: 10.1128/aac.02012-19] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 01/03/2020] [Indexed: 01/24/2023] Open
Abstract
Linezolid is increasingly used for the treatment of tuberculosis resistant to first-line agents, but the most effective dosing strategy is yet unknown. From November 2014 to November 2016, we randomized 114 drug-sensitive treatment-naive pulmonary tuberculosis patients from Cape Town, South Africa, to one of six 14-day treatment arms containing linezolid at 300 mg once daily (QD), 300 mg twice daily (BD), 600 mg QD, 600 mg BD, 1,200 mg QD, 1,200 mg three times per week (TIW), or a combination of isoniazid, rifampin, pyrazinamide, and ethambutol. Sixteen-hour sputum samples were collected overnight, and bactericidal activity was characterized by the daily percentage change in time to positivity (TTP) and the daily rate of change in log10(CFU). We also assessed the safety and pharmacokinetics of the study treatments. We found that bactericidal activity increased with increasing doses of linezolid. Based on the daily percentage change in TTP, activity was highest for 1,200 mg QD (4.5%; 95% Bayesian confidence interval [BCI], 3.3 to 5.6), followed by 600 mg BD (4.1%; BCI, 2.5 to 5.7), 600 mg QD (4.1%; BCI, 2.9 to 5.3), 300 mg BD (3.3%; BCI, 1.9 to 4.7), 300 mg QD (2.3%; BCI, 1.1 to 3.5), and 1,200 mg TIW (2.2%; BCI, 1.1 to 3.3). Similar results were seen with bactericidal activity characterized by the daily rate of change in CFU count. Antimycobacterial activity correlated positively with plasma drug exposure and percentage time over MIC. There were no unexpected adverse events. All linezolid doses showed bactericidal activity. For the same total daily dose, once-daily dosing proved to be at least as effective as a divided twice-daily dose. An intermittent dosing regimen, with 1,200 mg given three times weekly, showed the least activity. (This study has been registered at ClinicalTrials.gov under identifier NCT02279875.).
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Bolhuis MS, Akkerman OW, Sturkenboom MGG, Ghimire S, Srivastava S, Gumbo T, Alffenaar JWC. Linezolid-based Regimens for Multidrug-resistant Tuberculosis (TB): A Systematic Review to Establish or Revise the Current Recommended Dose for TB Treatment. Clin Infect Dis 2019; 67:S327-S335. [PMID: 30496467 DOI: 10.1093/cid/ciy625] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Linezolid has been successfully used for treatment of multidrug-resistant tuberculosis (MDR-TB). However, dose- and duration-related toxicity limit its use. Here, our aim was to search relevant pharmacokinetics (PK)/pharmacodynamics (PD) literature to identify the effective PK/PD index and to define the optimal daily dose and dosing frequency of linezolid in MDR-TB regimens. The systematic search resulted in 8 studies that met inclusion criteria. A significant PK variability was observed. Efficacy of linezolid seems to be driven by area under the concentration-time curve (AUC)/minimum inhibitory concentration (MIC). Literature is inconclusive about the preferred administration of a daily dose of 600 mg. To prevent development of drug resistance, an AUC/MIC ratio of 100 in the presence of a companion drug at relevant exposure is required. A daily dose of 600 mg seems appropriate to balance between efficacy and toxicity. Being a drug with a very narrow therapeutic window, linezolid treatment may benefit from a more personalized approach, that is, measuring actual MIC values and therapeutic drug monitoring.
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Affiliation(s)
- Mathieu S Bolhuis
- Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen
| | - Onno W Akkerman
- Pulmonary Diseases and Tuberculosis, University Medical Center Groningen, University of Groningen.,Tuberculosis Center Beatrixoord, University Medical Center Groningen, University of Groningen, Haren, The Netherlands
| | - Marieke G G Sturkenboom
- Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen
| | - Samiksha Ghimire
- Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Jan-Willem C Alffenaar
- Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen
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21
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Li Y, Huang H, Dong W, Lan T, Fan J, Wen S, Zhang T, Qin S, Guo A. Penetration of linezolid into bone tissue 24 h after administration in patients with multidrug-resistant spinal tuberculosis. PLoS One 2019; 14:e0223391. [PMID: 31581274 PMCID: PMC6776296 DOI: 10.1371/journal.pone.0223391] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 09/19/2019] [Indexed: 11/25/2022] Open
Abstract
Background Linezolid has shown strong antimicrobial activity against multidrug-resistant (MDR)/rifampin-resistant strains of Mycobacterium tuberculosis. Linezolid achieves clinical efficacy mainly through area under the concentration time curve/minimum inhibitory concentration ratio in the infected lesion site. Previous studies mainly focused on the relationship between linezolid concentrations in the blood and infected bone tissue when the blood drug concentration reached the peak 2 h after administration. However, we do not know whether linezolid can maintain the same bone/plasma ratio in infected bone tissue when the blood concentration reaches the trough level. Therefore, this study aimed to evaluate the penetrability of linezolid into bone tissue 24 h after administration in patients with MDR spinal tuberculosis (TB). Methods Nine MDR spinal TB patients, who received a treatment regimen including linezolid and underwent surgery, were enrolled prospectively from April 2017 to March 2019. Blood and diseased bone tissue specimens were collected simultaneously during operations 24 h after taking 600 mg of linezolid orally. Linezolid concentrations in plasma and diseased bone tissue specimens were determined by high-performance liquid chromatography–tandem mass spectrometry. Results Following a 600 mg oral administration of linezolid 24 h before surgery, median concentrations of linezolid in plasma and diseased bone tissue for the 9 patients were 1.98 mg/L (range 0.30–3.44 mg/L) and 0.60 mg/L (range 0.18–2.13 mg/L), respectively, at resection time. The median diseased bone/plasma linezolid concentration ratio was 0.48 (range 0.30–0.67). Pearson’s correlation analysis showed that linezolid concentrations in the plasma were positively related to those in diseased bone tissue (r = 0.949, p < 0.001). Conclusions After 24 h of medication, linezolid still had good penetrability into diseased bone tissue in patients with MDR spinal TB.
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Affiliation(s)
- Yuan Li
- Department of Orthopedics, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Department of Orthopedics, Beijing Chest Hospital, Capital Medical University, Beijing, China
| | - Hairong Huang
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing, China
| | - Weijie Dong
- Department of Orthopedics, Beijing Chest Hospital, Capital Medical University, Beijing, China
| | - Tinglong Lan
- Department of Orthopedics, Beijing Chest Hospital, Capital Medical University, Beijing, China
| | - Jun Fan
- Department of Orthopedics, Beijing Chest Hospital, Capital Medical University, Beijing, China
| | - Shu’an Wen
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing, China
| | - Tingting Zhang
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing, China
| | - Shibing Qin
- Department of Orthopedics, Beijing Chest Hospital, Capital Medical University, Beijing, China
- * E-mail: (AG); (SQ)
| | - Ai Guo
- Department of Orthopedics, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- * E-mail: (AG); (SQ)
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22
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Dose optimization of moxifloxacin and linezolid against tuberculosis using mathematical modeling and simulation. Int J Antimicrob Agents 2019; 53:275-283. [DOI: 10.1016/j.ijantimicag.2018.10.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 10/15/2018] [Accepted: 10/23/2018] [Indexed: 11/22/2022]
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Linezolid Pharmacokinetics in South African Patients with Drug-Resistant Tuberculosis and a High Prevalence of HIV Coinfection. Antimicrob Agents Chemother 2019; 63:AAC.02164-18. [PMID: 30617089 DOI: 10.1128/aac.02164-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 12/14/2018] [Indexed: 12/24/2022] Open
Abstract
The World Health Organization (WHO) recently recommended that linezolid be prioritized in treatment regimens for drug-resistant tuberculosis (TB), but there are limited data on its pharmacokinetics (PK) in patients with this disease. We conducted an observational study to explore covariate effects on linezolid PK and to estimate the probability of PK/pharmacodynamic target attainment in South African patients with drug-resistant TB. Consecutive adults on linezolid-based regimens were recruited in Cape Town and underwent intensive PK sampling at steady state. Noncompartmental analysis was performed. Thirty participants were included: 15 HIV positive, 26 on the initial dose of 600 mg daily, and 4 participants on 300 mg daily after dose reduction for linezolid-related toxicity. There was a negative correlation between body weight and exposure, with 17.4% (95% confidence interval [CI], 0.1 to 31.7) decrease in area under the concentration-time curve from 0 to 24 h (AUC0-24) per 10-kg weight increment after adjustment for other covariates. Age was an independent predictor of trough concentration, with an estimated 43.4% (95% CI, 5.9 to 94.2) increase per 10-year increment in age. The standard 600-mg dose achieved the efficacy target of free AUC/MIC of >119 at wild-type MIC values (≤0.5 mg/liter), but the probability of target attainment dropped to 61.5% (95% CI, 40.6 to 79.8) at the critical concentration of 1 mg/liter. When dosed at 600 mg daily, trough concentrations were above the toxicity threshold of 2 mg/liter in 57.7% (95% CI, 36.9 to 76.6). This confirms the narrow therapeutic index of linezolid, and alternative dosing strategies should be explored.
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Ding RD, Zhang HJ. Effect of linezolid on serum PCT, ESR, and CRP in patients with pulmonary tuberculosis and pneumonia. Medicine (Baltimore) 2018; 97:e12177. [PMID: 30212947 PMCID: PMC6155971 DOI: 10.1097/md.0000000000012177] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 08/09/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The continuous development of drug-resistant tuberculosis in recent years has brought new attention to tuberculosis. linezolid is usually used to treat infection in patients with pulmonary tuberculosis and pneumonia, for it has good effects on Mycobacterium tuberculosis, and has strong antibacterial activity on the drug-resistant strain. This study aims to investigate the effects of linezolid on serum procalcitonin (PCT), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) in patients with pulmonary tuberculosis and pneumonia. METHODS Forty patients with pulmonary tuberculosis and pneumonia were divided into 2 groups: observation group (n = 20), patients treated with linezolid; control group (n = 20), patients treated with moxifloxacin. At 14 days, one month and 3 months of treatment, changes in serum PCT, ESR, CRP, and bacterial eradication rate (negative conversion rate) were compared between the 2 groups, and the incidence of adverse reactions was compared. RESULTS Serum PCT, ESR, and CRP in the 2 groups were significantly lower after 14 days of treatment than before treatment (P < .05), the decrease was more significant in the observation group, and the differences in ESR and CRP were statistically significant (t = 2.199, 2.494, P < .05). Furthermore, the negative conversion rate was higher in the observation group, but the difference was not statistically significant (P > .05). At one month of treatment, serum PCT, ESR, and CRP were lower in the observation group, and the difference in CRP was statistically significant (t = 3.274, P < .05). Furthermore, the negative conversion rate was slightly higher in the observation group, but the difference was not statistically significant (P > .05). At 3 months of treatment, differences in PCT, ESR, and CRP were not statistically significant, and the negative conversion rate was the same between the 2 groups. Furthermore, the incidence of adverse reactions was higher in the observation group, but all were mild, and the differences between these 2 groups were not statistically significant (P > .05). CONCLUSION In the treatment of tuberculosis and pneumonia, linezolid can improve serum PCT, ESR, and CRP levels, and eradicate bacteria. However, adverse reactions should be strictly monitored to ensure its safety.
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Lyons MA. Modeling and Simulation of Pretomanid Pharmacokinetics in Pulmonary Tuberculosis Patients. Antimicrob Agents Chemother 2018; 62:e02359-17. [PMID: 29661865 PMCID: PMC6021621 DOI: 10.1128/aac.02359-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 04/09/2018] [Indexed: 01/28/2023] Open
Abstract
Pretomanid is a nitroimidazole antibiotic in late-phase clinical testing as a component of several novel antituberculosis (anti-TB) regimens. A population pharmacokinetic model for pretomanid was constructed using a Bayesian analysis of data from two phase 2 studies, PA-824-CL-007 and PA-824-CL-010, conducted with adult (median age, 27 years) patients in Cape Town, South Africa, with newly diagnosed pulmonary TB. Combined, these studies included 63 males and 59 females administered once-daily oral pretomanid doses of 50, 100, 150, 200, 600, 1,000, or 1,200 mg for 14 days. The observed pretomanid plasma concentration-time profiles for all tested doses were described by a one-compartment model with first-order absorption and elimination and a sigmoidal bioavailability dependent on dose, time, and the predose fed state. Allometric scaling with body weight (normalized to 70 kg) was used for volume of distribution and clearance, with the scaling exponents equal to 1 and 3/4, respectively. The posterior population geometric means for the clearance and volume of distribution allometric constants were 4.8 ± 0.2 liters/h and 130 ± 5 liters, respectively, and the posterior population geometric mean for the half-maximum-effect dose for the reduction of bioavailability was 450 ± 50 mg. Interindividual variability, described by the percent coefficient of variation, was 32% ± 3% for clearance, 17% ± 4% for the volume of distribution, and 74% ± 9% for the half-maximum-effect dose. This model provides a dose-exposure relationship for pretomanid in adult TB patients with potential applications to dose selection in individuals and to further clinical testing of novel pretomanid-containing anti-TB regimens.
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Affiliation(s)
- Michael A Lyons
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
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Lange C, Alghamdi WA, Al-Shaer MH, Brighenti S, Diacon AH, DiNardo AR, Grobbel HP, Gröschel MI, von Groote-Bidlingmaier F, Hauptmann M, Heyckendorf J, Köhler N, Kohl TA, Merker M, Niemann S, Peloquin CA, Reimann M, Schaible UE, Schaub D, Schleusener V, Thye T, Schön T. Perspectives for personalized therapy for patients with multidrug-resistant tuberculosis. J Intern Med 2018; 284:163-188. [PMID: 29806961 DOI: 10.1111/joim.12780] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
According to the World Health Organization (WHO), tuberculosis is the leading cause of death attributed to a single microbial pathogen worldwide. In addition to the large number of patients affected by tuberculosis, the emergence of Mycobacterium tuberculosis drug-resistance is complicating tuberculosis control in many high-burden countries. During the past 5 years, the global number of patients identified with multidrug-resistant tuberculosis (MDR-TB), defined as bacillary resistance at least against rifampicin and isoniazid, the two most active drugs in a treatment regimen, has increased by more than 20% annually. Today we experience a historical peak in the number of patients affected by MDR-TB. The management of MDR-TB is characterized by delayed diagnosis, uncertainty of the extent of bacillary drug-resistance, imprecise standardized drug regimens and dosages, very long duration of therapy and high frequency of adverse events which all translate into a poor prognosis for many of the affected patients. Major scientific and technological advances in recent years provide new perspectives through treatment regimens tailor-made to individual needs. Where available, such personalized treatment has major implications on the treatment outcomes of patients with MDR-TB. The challenge now is to bring these adances to those patients that need them most.
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Affiliation(s)
- C Lange
- Clinical Infectious Diseases, Research Center Borstel, Borstel, Germany
- Tuberculosis Unit, German Center for Infection Research (DZIF), Borstel, Germany
- International Health/Infectious Diseases, University of Lübeck, Lübeck, Germany
- Department of Medicine, Karolinska Institute, Stockholm, Sweden
| | - W A Alghamdi
- Department of Pharmacotherapy and Translational Research, Infectious Disease Pharmacokinetics Laboratory, College of Pharmacy, University of Florida, Gainesville, FL, USA
| | - M H Al-Shaer
- Department of Pharmacotherapy and Translational Research, Infectious Disease Pharmacokinetics Laboratory, College of Pharmacy, University of Florida, Gainesville, FL, USA
| | - S Brighenti
- Department of Medicine, Center for Infectious Medicine (CIM), Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - A H Diacon
- Task Applied Science, Bellville, South Africa
- Division of Physiology, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - A R DiNardo
- Section of Global and Immigrant Health, Baylor College of Medicine, Houston, TX, USA
| | - H P Grobbel
- Clinical Infectious Diseases, Research Center Borstel, Borstel, Germany
- Tuberculosis Unit, German Center for Infection Research (DZIF), Borstel, Germany
- International Health/Infectious Diseases, University of Lübeck, Lübeck, Germany
| | - M I Gröschel
- Department of Pumonary Diseases & Tuberculosis, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
- Molecular and Experimental Mycobacteriology, National Reference Center for Mycobacteria, Research Center Borstel, Borstel, Germany
| | | | - M Hauptmann
- Tuberculosis Unit, German Center for Infection Research (DZIF), Borstel, Germany
- Cellular Microbiology, Research Center Borstel, Borstel, Germany
| | - J Heyckendorf
- Clinical Infectious Diseases, Research Center Borstel, Borstel, Germany
- Tuberculosis Unit, German Center for Infection Research (DZIF), Borstel, Germany
- International Health/Infectious Diseases, University of Lübeck, Lübeck, Germany
| | - N Köhler
- Clinical Infectious Diseases, Research Center Borstel, Borstel, Germany
- Tuberculosis Unit, German Center for Infection Research (DZIF), Borstel, Germany
- International Health/Infectious Diseases, University of Lübeck, Lübeck, Germany
| | - T A Kohl
- Molecular and Experimental Mycobacteriology, National Reference Center for Mycobacteria, Research Center Borstel, Borstel, Germany
| | - M Merker
- Molecular and Experimental Mycobacteriology, National Reference Center for Mycobacteria, Research Center Borstel, Borstel, Germany
| | - S Niemann
- Tuberculosis Unit, German Center for Infection Research (DZIF), Borstel, Germany
- Molecular and Experimental Mycobacteriology, National Reference Center for Mycobacteria, Research Center Borstel, Borstel, Germany
| | - C A Peloquin
- Department of Pharmacotherapy and Translational Research, Infectious Disease Pharmacokinetics Laboratory, College of Pharmacy, University of Florida, Gainesville, FL, USA
| | - M Reimann
- Clinical Infectious Diseases, Research Center Borstel, Borstel, Germany
- Tuberculosis Unit, German Center for Infection Research (DZIF), Borstel, Germany
- International Health/Infectious Diseases, University of Lübeck, Lübeck, Germany
| | - U E Schaible
- Tuberculosis Unit, German Center for Infection Research (DZIF), Borstel, Germany
- Cellular Microbiology, Research Center Borstel, Borstel, Germany
- Biochemical Microbiology & Immunochemistry, University of Lübeck, Lübeck, Germany
- LRA INFECTIONS'21, Borstel, Germany
| | - D Schaub
- Clinical Infectious Diseases, Research Center Borstel, Borstel, Germany
- Tuberculosis Unit, German Center for Infection Research (DZIF), Borstel, Germany
- International Health/Infectious Diseases, University of Lübeck, Lübeck, Germany
| | - V Schleusener
- Molecular and Experimental Mycobacteriology, National Reference Center for Mycobacteria, Research Center Borstel, Borstel, Germany
| | - T Thye
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - T Schön
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
- Department of Clinical Microbiology and Infectious Diseases, Kalmar County Hospital, Linköping University, Linköping, Sweden
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Population Pharmacokinetics of AZD-5847 in Adults with Pulmonary Tuberculosis. Antimicrob Agents Chemother 2017; 61:AAC.01066-17. [PMID: 28739794 DOI: 10.1128/aac.01066-17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 07/14/2017] [Indexed: 01/15/2023] Open
Abstract
AZD-5847 is a new oxazolidinone derivative under development for the treatment of tuberculosis (TB). Here we describe the population pharmacokinetics (PK) of AZD-5847 in patients with tuberculosis based on a recently completed phase II study. The study included 60 patients with drug-susceptible TB. Patients were randomized to four dosages (500 mg once daily, 1,200 mg once daily, 500 mg twice daily, and 800 mg twice daily). Patients were intensively sampled on days 1 and 14. AZD-5847 pharmacokinetics were best described with a two-compartment model with lag time (Tlag) for absorption. AZD-5847 bioavailability was nonlinear and plateaued at 800 mg. We performed deterministic simulation to compare the PK/pharmacodynamics (PD) of AZD-5847, linezolid, and sutezolid. AZD-5847 PK/PD in terms of both area under the concentration-time curve for the free, unbound fraction (fAUC)/MIC and time the free concentration was above the MIC (fT>MIC) were less favorable than those for linezolid and sutezolid. This could help explain the poor bactericidal activity of AZD-5847 in the recent phase II study.
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Wasserman S, Meintjes G, Maartens G. Linezolid in the treatment of drug-resistant tuberculosis: the challenge of its narrow therapeutic index. Expert Rev Anti Infect Ther 2016; 14:901-15. [PMID: 27532292 DOI: 10.1080/14787210.2016.1225498] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
INTRODUCTION Linezolid is an oxazolidinone with potent activity against M tuberculosis, and improves culture conversion and cure rates when added to treatment regimens for drug resistant tuberculosis. However, linezolid has a narrow therapeutic window, and the optimal dosing strategy that minimizes the substantial toxicity associated with linezolid's prolonged use in tuberculosis treatment has not been determined, limiting the potential impact of this anti-mycobacterial agent. AREAS COVERED This paper aims to review and summarize the current knowledge on linezolid for the treatment of drug-resistant tuberculosis. The focus is on the pharmacokinetic-pharmacodynamic determinants of linezolid's efficacy and toxicity in tuberculosis, and how this relates to defining an optimal dose. Mechanisms of linezolid toxicity and resistance, and the potential role of therapeutic drug monitoring are also covered. Expert commentary: Prospective pharmacokinetic-pharmacodynamic studies are required to define optimal therapeutic targets and to inform improved linezolid dosing strategies for drug-resistant tuberculosis.
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Affiliation(s)
- Sean Wasserman
- a Division of Infectious Diseases and HIV Medicine, Department of Medicine , University of Cape Town , Cape Town , South Africa
| | - Graeme Meintjes
- a Division of Infectious Diseases and HIV Medicine, Department of Medicine , University of Cape Town , Cape Town , South Africa.,b Clinical Infectious Diseases Research Initiative, Institute of Infectious Diseases and Molecular Medicine, Faculty of Health Sciences , University of Cape Town , Cape Town , South Africa
| | - Gary Maartens
- c Division of Clinical Pharmacology, Department of Medicine , University of Cape Town , Cape Town , South Africa
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Contribution of Oxazolidinones to the Efficacy of Novel Regimens Containing Bedaquiline and Pretomanid in a Mouse Model of Tuberculosis. Antimicrob Agents Chemother 2015; 60:270-7. [PMID: 26503656 DOI: 10.1128/aac.01691-15] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 10/16/2015] [Indexed: 11/20/2022] Open
Abstract
New regimens based on two or more novel agents are sought to shorten or simplify treatment of tuberculosis (TB). Pretomanid (PMD) is a nitroimidazole in phase 3 trials that has significant bactericidal activity alone and in combination with bedaquiline (BDQ) and/or pyrazinamide (PZA). We previously showed that the novel combination of BDQ+PMD plus the oxazolidinone sutezolid (SZD) had sterilizing activity superior to that of the first-line regimen in a murine model of TB. The present experiments compared the activity of different oxazolidinones in combination with BDQ+PMD with or without PZA in the same model. The 3-drug regimen of BDQ+PMD plus linezolid (LZD) had sterilizing activity approaching that of BDQ+PMD+SZD and superior to that of the first-line regimen. The addition of PZA further enhanced activity. Reducing the duration of LZD to 1 month did not significantly affect the activity of the regimen. Halving the LZD dose or replacing LZD with RWJ-416457 modestly reduced activity over the first month but not after 2 months. AZD5847 and tedizolid also increased the bactericidal activity of BDQ+PMD, but they were less effective than the other oxazolidinones. These results provide optimism for safe, short-course oral regimens for drug-resistant TB that may also be superior to the current first-line regimen for drug-susceptible TB.
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Maartens G, Benson CA. Linezolid for Treating Tuberculosis: A Delicate Balancing Act. EBioMedicine 2015; 2:1568-9. [PMID: 26870767 PMCID: PMC4740312 DOI: 10.1016/j.ebiom.2015.10.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 10/10/2015] [Indexed: 01/12/2023] Open
Affiliation(s)
- Gary Maartens
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, South Africa
| | - Constance A Benson
- Division of Infectious Diseases, School of Medicine, University of California San Diego, USA
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Jeong BH, Jeon K, Park HY, Kwon OJ, Lee KS, Kim HK, Choi YS, Kim J, Huh HJ, Lee NY, Koh WJ. Outcomes of pulmonary MDR-TB: impacts of fluoroquinolone resistance and linezolid treatment. J Antimicrob Chemother 2015. [DOI: 10.1093/jac/dkv215] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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Coleman MT, Chen RY, Lee M, Lin PL, Dodd LE, Maiello P, Via LE, Kim Y, Marriner G, Dartois V, Scanga C, Janssen C, Wang J, Klein E, Cho SN, Barry CE, Flynn JL. PET/CT imaging reveals a therapeutic response to oxazolidinones in macaques and humans with tuberculosis. Sci Transl Med 2014; 6:265ra167. [PMID: 25473035 PMCID: PMC6413515 DOI: 10.1126/scitranslmed.3009500] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Oxazolidinone antibiotics such as linezolid have shown significant therapeutic effects in patients with extensively drug-resistant (XDR) tuberculosis (TB) despite modest effects in rodents and no demonstrable early bactericidal activity in human phase 2 trials. We show that monotherapy with either linezolid or AZD5847, a second-generation oxazolidinone, reduced bacterial load at necropsy in Mycobacterium tuberculosis-infected cynomolgus macaques with active TB. This effect coincided with a decline in 2-deoxy-2-[(18)F]-fluoro-d-glucose positron emission tomography (FDG PET) imaging avidity in the lungs of these animals and with reductions in pulmonary pathology measured by serial computed tomography (CT) scans over 2 months of monotherapy. In a parallel phase 2 clinical study of linezolid in patients infected with XDR-TB, we also collected PET/CT imaging data from subjects receiving linezolid that had been added to their failing treatment regimens. Quantitative comparisons of PET/CT imaging changes in these human subjects were similar in magnitude to those observed in macaques, demonstrating that the therapeutic effect of these oxazolidinones can be reproduced in this model of experimental chemotherapy. PET/CT imaging may be useful as an early quantitative measure of drug efficacy against TB in human patients.
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Affiliation(s)
- M Teresa Coleman
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA
| | - Ray Y Chen
- Tuberculosis Research Section, Laboratory of Clinical Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Myungsun Lee
- International Tuberculosis Research Center, Changwon 631-710, Republic of Korea
| | - Philana Ling Lin
- Department of Pediatrics, Children's Hospital of Pittsburgh of the University of Pittsburgh Medical Center, Pittsburgh, PA 15260, USA
| | - Lori E Dodd
- Biostatistics Research Branch, NIAID, NIH, Bethesda, MD 20892, USA
| | - Pauline Maiello
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA
| | - Laura E Via
- Tuberculosis Research Section, Laboratory of Clinical Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Youngran Kim
- International Tuberculosis Research Center, Changwon 631-710, Republic of Korea
| | - Gwendolyn Marriner
- Tuberculosis Research Section, Laboratory of Clinical Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Veronique Dartois
- Public Health Research Institute Center, Rutgers New Jersey Medical School, Newark, NJ 07103, USA
| | - Charles Scanga
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA
| | - Christopher Janssen
- Division of Laboratory Animal Resources, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Jing Wang
- Clinical Research Directorate/Clinical Monitoring Research Program, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21701, USA
| | - Edwin Klein
- Division of Laboratory Animal Resources, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Sang Nae Cho
- International Tuberculosis Research Center, Changwon 631-710, Republic of Korea. Department of Microbiology, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea
| | - Clifton E Barry
- Tuberculosis Research Section, Laboratory of Clinical Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA. Institute of Infectious Disease and Molecular Medicine, and the Department of Clinical Laboratory Sciences, Faculty of Health Sciences, University of Cape Town, Rondebosch 7701, South Africa.
| | - JoAnne L Flynn
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA.
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Poce G, Cocozza M, Consalvi S, Biava M. SAR analysis of new anti-TB drugs currently in pre-clinical and clinical development. Eur J Med Chem 2014; 86:335-51. [PMID: 25173852 DOI: 10.1016/j.ejmech.2014.08.066] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 07/22/2014] [Accepted: 08/25/2014] [Indexed: 12/14/2022]
Abstract
Despite enormous efforts have been made in the hunt for new drugs, tuberculosis (TB) still remains the first bacterial cause of mortality worldwide, causing an estimated 8.6 million new cases and 1.3 million deaths in 2012. Multi-drug resistant-TB strains no longer respond to first-line drugs and are inexorably spreading with an estimated 650,000 cases as well as extensively-drug resistant-TB strains, which are resistant to any fluoroquinolone and at least one of the second-line drugs, with 60,000 cases. Thus the discovery and development of new medicines is a major keystone for tuberculosis treatment and control. After decades of dormancy in the field of TB drug development, recent efforts from various groups have generated a promising TB drug pipeline. Several new therapeutic agents are concurrently studied in clinical trials together with much activity in the hittolead and lead optimization stages. In this article we will review the recent advances in TB drug discovery with a special focus on structure activity relationship studies of the most advanced compound classes.
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Affiliation(s)
- Giovanna Poce
- Dipartimento di Chimica e Tecnologie del Farmaco, Università "La Sapienza", Piazzale Aldo Moro 5, I-00185 Roma, Italy
| | - Martina Cocozza
- Dipartimento di Chimica e Tecnologie del Farmaco, Università "La Sapienza", Piazzale Aldo Moro 5, I-00185 Roma, Italy
| | - Sara Consalvi
- Dipartimento di Chimica e Tecnologie del Farmaco, Università "La Sapienza", Piazzale Aldo Moro 5, I-00185 Roma, Italy
| | - Mariangela Biava
- Dipartimento di Chimica e Tecnologie del Farmaco, Università "La Sapienza", Piazzale Aldo Moro 5, I-00185 Roma, Italy.
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Risk factors for linezolid-associated thrombocytopenia in adult patients. Infection 2014; 42:1007-12. [PMID: 25119433 PMCID: PMC4226929 DOI: 10.1007/s15010-014-0674-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 07/28/2014] [Indexed: 12/21/2022]
Abstract
Objectives Thrombocytopenia (TP) is a common adverse effect of linezolid (LZD). However, risk factors for LZD-associated TP have been reported in Western patients with relatively heavy body weight. The aim of this study was to determine the risk factors for LZD-associated TP in Asian population. Materials and methods A retrospective cohort study was conducted among 101 consecutive patients who received LZD therapy (1,200 mg/day) between July 2003 and December 2013 at a tertiary referral hospital in Tokyo, Japan. The patients with obvious other causes for TP were excluded. The information of target infectious disease, patients’ age, gender, body weight, body mass index, baseline serum creatinine (SCr), baseline platelet count, and treatment duration was collected retrospectively. TP was defined as ≥50 % decrease in platelet count from baseline. Bi- and multi-variate analyses were performed. Results A total of 101 patients were included (mean age [SD] 64 [18]; male gender [%], 57 [56]). Median duration [range] of LZD therapy was 14 days [1–67]. LZD-associated TP was identified in 42 patients (42 %). For TP, adjusted odds ratio (OR) [95 % CI] of daily per kg dose (DPKD) and SCr was 1.14 [1.05–1.26] and 1.51 [1.01–2.50], respectively. Conclusions Higher DPKD and elevated SCr are significantly associated with LZD-associated TP. These findings suggest that daily dose of LZD should be adjusted using body weight, as typically done in pediatrics, in adults as well. Renal function also should be considered for dose adjustment.
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Drusano GL, Neely M, Van Guilder M, Schumitzky A, Brown D, Fikes S, Peloquin C, Louie A. Analysis of combination drug therapy to develop regimens with shortened duration of treatment for tuberculosis. PLoS One 2014; 9:e101311. [PMID: 25003557 PMCID: PMC4086932 DOI: 10.1371/journal.pone.0101311] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 06/05/2014] [Indexed: 11/28/2022] Open
Abstract
Rationale Tuberculosis remains a worldwide problem, particularly with the advent of multi-drug resistance. Shortening therapy duration for Mycobacterium tuberculosis is a major goal, requiring generation of optimal kill rate and resistance-suppression. Combination therapy is required to attain the goal of shorter therapy. Objectives Our objective was to identify a method for identifying optimal combination chemotherapy. We developed a mathematical model for attaining this end. This is accomplished by identifying drug effect interaction (synergy, additivity, antagonism) for susceptible organisms and subpopulations resistant to each drug in the combination. Methods We studied the combination of linezolid plus rifampin in our hollow fiber infection model. We generated a fully parametric drug effect interaction mathematical model. The results were subjected to Monte Carlo simulation to extend the findings to a population of patients by accounting for between-patient variability in drug pharmacokinetics. Results All monotherapy allowed emergence of resistance over the first two weeks of the experiment. In combination, the interaction was additive for each population (susceptible and resistant). For a 600 mg/600 mg daily regimen of linezolid plus rifampin, we demonstrated that >50% of simulated subjects had eradicated the susceptible population by day 27 with the remaining organisms resistant to one or the other drug. Only 4% of patients had complete organism eradication by experiment end. Discussion These data strongly suggest that in order to achieve the goal of shortening therapy, the original regimen may need to be changed at one month to a regimen of two completely new agents with resistance mechanisms independent of the initial regimen. This hypothesis which arose from the analysis is immediately testable in a clinical trial.
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Affiliation(s)
- George L. Drusano
- Institute for Therapeutic Innovation, College of Medicine, University of Florida, Lake Nona, Florida, United States of America
- * E-mail:
| | - Michael Neely
- Laboratory of Applied Pharmacokinetics, School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Michael Van Guilder
- Laboratory of Applied Pharmacokinetics, School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Alan Schumitzky
- Laboratory of Applied Pharmacokinetics, School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - David Brown
- Institute for Therapeutic Innovation, College of Medicine, University of Florida, Lake Nona, Florida, United States of America
| | - Steven Fikes
- Institute for Therapeutic Innovation, College of Medicine, University of Florida, Lake Nona, Florida, United States of America
| | - Charles Peloquin
- Infectious Diseases PK Laboratory, College of Pharmacy, University of Florida, Gainesville, Florida, United States of America
| | - Arnold Louie
- Institute for Therapeutic Innovation, College of Medicine, University of Florida, Lake Nona, Florida, United States of America
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Lange C, Abubakar I, Alffenaar JWC, Bothamley G, Caminero JA, Carvalho ACC, Chang KC, Codecasa L, Correia A, Crudu V, Davies P, Dedicoat M, Drobniewski F, Duarte R, Ehlers C, Erkens C, Goletti D, Günther G, Ibraim E, Kampmann B, Kuksa L, de Lange W, van Leth F, van Lunzen J, Matteelli A, Menzies D, Monedero I, Richter E, Rüsch-Gerdes S, Sandgren A, Scardigli A, Skrahina A, Tortoli E, Volchenkov G, Wagner D, van der Werf MJ, Williams B, Yew WW, Zellweger JP, Cirillo DM. Management of patients with multidrug-resistant/extensively drug-resistant tuberculosis in Europe: a TBNET consensus statement. Eur Respir J 2014; 44:23-63. [PMID: 24659544 PMCID: PMC4076529 DOI: 10.1183/09031936.00188313] [Citation(s) in RCA: 189] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) substantially challenges TB control, especially in the European Region of the World Health Organization, where the highest prevalence of MDR/XDR cases is reported. The current management of patients with MDR/XDR-TB is extremely complex for medical, social and public health systems. The treatment with currently available anti-TB therapies to achieve relapse-free cure is long and undermined by a high frequency of adverse drug events, suboptimal treatment adherence, high costs and low treatment success rates. Availability of optimal management for patients with MDR/XDR-TB is limited even in the European Region. In the absence of a preventive vaccine, more effective diagnostic tools and novel therapeutic interventions the control of MDR/XDR-TB will be extremely difficult. Despite recent scientific advances in MDR/XDR-TB care, decisions for the management of patients with MDR/XDR-TB and their contacts often rely on expert opinions, rather than on clinical evidence. This document summarises the current knowledge on the prevention, diagnosis and treatment of adults and children with MDR/XDR-TB and their contacts, and provides expert consensus recommendations on questions where scientific evidence is still lacking. TBNET consensus statement on the management of patients with MDR/XDR-TB has been released in theEur Respir Jhttp://ow.ly/uizRD
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Affiliation(s)
- Christoph Lange
- For the authors' affiliations see the Acknowledgements section
| | | | | | | | - Jose A Caminero
- For the authors' affiliations see the Acknowledgements section
| | | | - Kwok-Chiu Chang
- For the authors' affiliations see the Acknowledgements section
| | - Luigi Codecasa
- For the authors' affiliations see the Acknowledgements section
| | - Ana Correia
- For the authors' affiliations see the Acknowledgements section
| | - Valeriu Crudu
- For the authors' affiliations see the Acknowledgements section
| | - Peter Davies
- For the authors' affiliations see the Acknowledgements section
| | - Martin Dedicoat
- For the authors' affiliations see the Acknowledgements section
| | | | - Raquel Duarte
- For the authors' affiliations see the Acknowledgements section
| | - Cordula Ehlers
- For the authors' affiliations see the Acknowledgements section
| | - Connie Erkens
- For the authors' affiliations see the Acknowledgements section
| | - Delia Goletti
- For the authors' affiliations see the Acknowledgements section
| | - Gunar Günther
- For the authors' affiliations see the Acknowledgements section
| | - Elmira Ibraim
- For the authors' affiliations see the Acknowledgements section
| | - Beate Kampmann
- For the authors' affiliations see the Acknowledgements section
| | - Liga Kuksa
- For the authors' affiliations see the Acknowledgements section
| | - Wiel de Lange
- For the authors' affiliations see the Acknowledgements section
| | - Frank van Leth
- For the authors' affiliations see the Acknowledgements section
| | - Jan van Lunzen
- For the authors' affiliations see the Acknowledgements section
| | | | - Dick Menzies
- For the authors' affiliations see the Acknowledgements section
| | | | - Elvira Richter
- For the authors' affiliations see the Acknowledgements section
| | | | | | - Anna Scardigli
- For the authors' affiliations see the Acknowledgements section
| | - Alena Skrahina
- For the authors' affiliations see the Acknowledgements section
| | - Enrico Tortoli
- For the authors' affiliations see the Acknowledgements section
| | | | - Dirk Wagner
- For the authors' affiliations see the Acknowledgements section
| | | | - Bhanu Williams
- For the authors' affiliations see the Acknowledgements section
| | - Wing-Wai Yew
- For the authors' affiliations see the Acknowledgements section
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Garcia-Prats AJ, Rose PC, Hesseling AC, Schaaf HS. Linezolid for the treatment of drug-resistant tuberculosis in children: A review and recommendations. Tuberculosis (Edinb) 2014; 94:93-104. [DOI: 10.1016/j.tube.2013.10.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 10/11/2013] [Accepted: 10/20/2013] [Indexed: 11/30/2022]
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The emergence of linezolid resistance among Enterococci in intestinal microbiota of treated patients is unrelated to individual pharmacokinetic characteristics. Antimicrob Agents Chemother 2014; 58:2681-7. [PMID: 24566182 DOI: 10.1128/aac.02251-13] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Linezolid is an antimicrobial agent for the treatment of multiresistant Gram-positive infections. We assessed the impact of linezolid on the microbiota and the emergence of resistance and investigated its relationship with plasma pharmacokinetics of the antibiotic. Twenty-eight patients were treated for the first time with linezolid administered orally (n = 17) or parenterally (n = 11) at 600 mg twice a day. Linezolid plasma pharmacokinetic analysis was performed on day 7. Colonization by fecal enterococci, pharyngeal streptococci, and nasal staphylococci were assessed using selective media with or without supplemental linezolid. The resistance to linezolid was characterized. The treatment led to a decrease of enterococci, staphylococci, and streptococci in the fecal (P = 0.03), nasal, and pharyngeal (P < 0.01) microbiotas. The appearance of resistant strains was observed only in enterococci from the fecal microbiota between the 7th and 21st days of treatment in four patients (14.3%). The resistance was mainly due for the first time to the mutation G2447T in the 23S rRNA gene. No pharmacokinetic parameters were significantly different between the patients, regardless of the appearance of resistance. The emergence of linezolid resistance during treatment was observed only in the intestinal microbiota and unrelated to pharmacokinetic parameters. However, colonization by Gram-positive bacteria was reduced as a result of treatment in all microbiotas.
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Nukui Y, Hatakeyama S, Okamoto K, Yamamoto T, Hisaka A, Suzuki H, Yata N, Yotsuyanagi H, Moriya K. High plasma linezolid concentration and impaired renal function affect development of linezolid-induced thrombocytopenia. J Antimicrob Chemother 2013; 68:2128-33. [DOI: 10.1093/jac/dkt133] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Vu DH, Bolhuis MS, Koster RA, Greijdanus B, de Lange WCM, van Altena R, Brouwers JRBJ, Uges DRA, Alffenaar JWC. Dried blood spot analysis for therapeutic drug monitoring of linezolid in patients with multidrug-resistant tuberculosis. Antimicrob Agents Chemother 2012; 56:5758-63. [PMID: 22926568 PMCID: PMC3486591 DOI: 10.1128/aac.01054-12] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 08/18/2012] [Indexed: 11/20/2022] Open
Abstract
Linezolid is a promising antimicrobial agent for the treatment of multidrug-resistant tuberculosis (MDR-TB), but its use is limited by toxicity. Therapeutic drug monitoring (TDM) may help to minimize toxicity while adequate drug exposure is maintained. Conventional plasma sampling and monitoring might be hindered in many parts of the world by logistical problems that may be solved by dried blood spot (DBS) sampling. The aim of this study was to develop and validate a novel method for TDM of linezolid in MDR-TB patients using DBS sampling. Plasma, venous DBS, and capillary DBS specimens were obtained simultaneously from eight patients receiving linezolid. A DBS sampling method was developed and clinically validated by comparing DBS with plasma results using Passing-Bablok regression and Bland-Altman analysis. This study showed that DBS analysis was reproducible and robust. Accuracy and between- and within-day precision values from three validations presented as bias and coefficient of variation (CV) were less than 17.2% for the lower limit of quantification and less than 7.8% for other levels. The method showed a high recovery of approximately 95% and a low matrix effect of less than 8.7%. DBS specimens were stable at 37°C for 2 months and at 50°C for 1 week. The ratio of the concentration of linezolid in DBS samples to that in plasma was 1.2 (95% confidence interval [CI], 1.12 to 1.27). Linezolid exposure calculated from concentrations DBS samples and plasma showed good agreement. In conclusion, DBS analysis of linezolid is a promising tool to optimize linezolid treatment in MDR-TB patients. An easy sampling procedure and high sample stability may facilitate TDM, even in underdeveloped countries with limited resources and where conventional plasma sampling is not feasible.
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Affiliation(s)
- D. H. Vu
- University of Groningen, Department of Pharmacotherapy and Pharmaceutical Care, Groningen, The Netherlands
- University of Groningen, University Medical Center Groningen, Department of Hospital and Clinical Pharmacy, Groningen, The Netherlands
- Hanoi University of Pharmacy, Hanoi, Vietnam
| | - M. S. Bolhuis
- University of Groningen, University Medical Center Groningen, Department of Hospital and Clinical Pharmacy, Groningen, The Netherlands
| | - R. A. Koster
- University of Groningen, University Medical Center Groningen, Department of Hospital and Clinical Pharmacy, Groningen, The Netherlands
| | - B. Greijdanus
- University of Groningen, University Medical Center Groningen, Department of Hospital and Clinical Pharmacy, Groningen, The Netherlands
| | - W. C. M. de Lange
- University of Groningen, University Medical Center Groningen, Tuberculosis Center Beatrixoord, Haren, The Netherlands
| | - R. van Altena
- University of Groningen, University Medical Center Groningen, Tuberculosis Center Beatrixoord, Haren, The Netherlands
| | - J. R. B. J. Brouwers
- University of Groningen, Department of Pharmacotherapy and Pharmaceutical Care, Groningen, The Netherlands
| | - D. R. A. Uges
- University of Groningen, University Medical Center Groningen, Department of Hospital and Clinical Pharmacy, Groningen, The Netherlands
| | - J. W. C. Alffenaar
- University of Groningen, University Medical Center Groningen, Department of Hospital and Clinical Pharmacy, Groningen, The Netherlands
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Lee M, Lee J, Carroll MW, Choi H, Min S, Song T, Via LE, Goldfeder LC, Kang E, Jin B, Park H, Kwak H, Kim H, Jeon HS, Jeong I, Joh JS, Chen RY, Olivier KN, Shaw PA, Follmann D, Song SD, Lee JK, Lee D, Kim CT, Dartois V, Park SK, Cho SN, Barry CE. Linezolid for treatment of chronic extensively drug-resistant tuberculosis. N Engl J Med 2012; 367:1508-18. [PMID: 23075177 PMCID: PMC3814175 DOI: 10.1056/nejmoa1201964] [Citation(s) in RCA: 410] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Linezolid has antimycobacterial activity in vitro and is increasingly used for patients with highly drug-resistant tuberculosis. METHODS We enrolled 41 patients who had sputum-culture-positive extensively drug-resistant (XDR) tuberculosis and who had not had a response to any available chemotherapeutic option during the previous 6 months. Patients were randomly assigned to linezolid therapy that started immediately or after 2 months, at a dose of 600 mg per day, without a change in their background regimen. The primary end point was the time to sputum-culture conversion on solid medium, with data censored 4 months after study entry. After confirmed sputum-smear conversion or 4 months (whichever came first), patients underwent a second randomization to continued linezolid therapy at a dose of 600 mg per day or 300 mg per day for at least an additional 18 months, with careful toxicity monitoring. RESULTS By 4 months, 15 of the 19 patients (79%) in the immediate-start group and 7 of the 20 (35%) in the delayed-start group had culture conversion (P=0.001). Most patients (34 of 39 [87%]) had a negative sputum culture within 6 months after linezolid had been added to their drug regimen. Of the 38 patients with exposure to linezolid, 31 (82%) had clinically significant adverse events that were possibly or probably related to linezolid, including 3 patients who discontinued therapy. Patients who received 300 mg per day after the second randomization had fewer adverse events than those who continued taking 600 mg per day. Thirteen patients completed therapy and have not had a relapse. Four cases of acquired resistance to linezolid have been observed. CONCLUSIONS Linezolid is effective at achieving culture conversion among patients with treatment-refractory XDR pulmonary tuberculosis, but patients must be monitored carefully for adverse events. (Funded by the National Institute of Allergy and Infectious Diseases and the Ministry of Health and Welfare, South Korea; ClinicalTrials.gov number, NCT00727844.).
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Affiliation(s)
- Myungsun Lee
- International Tuberculosis Research Center, Changwon, South Korea
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Field SK, Fisher D, Jarand JM, Cowie RL. New treatment options for multidrug-resistant tuberculosis. Ther Adv Respir Dis 2012; 6:255-68. [PMID: 22763676 DOI: 10.1177/1753465812452193] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Despite the development of effective treatments, tuberculosis (TB) remains a major health problem. TB continues to infect new victims and kills nearly 2 million people annually. The problem is much greater in resource-limited countries but is present worldwide. Inadequate public health resources, cost, the obligatory long treatment period, and adverse drug effects contribute to treatment failures and relapses. Drug-resistant Mycobacterium tuberculosis (MTB) strains arise spontaneously and are propagated by inadequate treatment. According to World Health Organization global data, 17% of MTB strains in new, previously untreated cases are resistant to at least one drug. Approximately, 3.3% of new MTB cases are resistant to both isoniazid and rifampin, also called multidrug resistant (MDR), and rates of MDR-TB are greater than 60% in previously treated patients in some countries. Approximately 5% of cases of MDR-TB are also resistant to fluoroquinolones and to injectable drugs, and are called extensively drug resistant (XDR). Recently, XDR strains have been isolated that are also resistant to all standard second-line anti-TB medications. Successful drug treatment of TB with complex resistance profiles is virtually impossible with currently available drugs. There is a desperate need for new compounds that cure strains resistant to currently available drugs and for drugs that are better tolerated and will shorten treatment regimens. In the short term, new strategies for the management of drug-resistant TB with currently available drugs are being explored. These include the use of high-dose isoniazid, substitution of rifabutin in a small proportion of rifampin-resistant cases, linezolid, fluoroquinolones, and phenothiazines. A number of novel drugs are undergoing clinical testing and will hopefully be available in the near future. These include the newer oxazolidinones, diarylquinolines, nitroimidazopyrans, ethenylenediamines, pyrroles, and benzothiazinones.
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Affiliation(s)
- Stephen K Field
- Health Science Centre, 3330 Hospital Dr. NW, Calgary, Alberta, Canada.
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Evaluation of standard- and high-dose daptomycin versus linezolid against vancomycin-resistant Enterococcus isolates in an in vitro pharmacokinetic/pharmacodynamic model with simulated endocardial vegetations. Antimicrob Agents Chemother 2012; 56:3174-80. [PMID: 22470111 DOI: 10.1128/aac.06439-11] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Daptomycin MICs for enterococci are typically 1- to 2-fold higher than those for Staphylococcus aureus, and there is an imminent need to establish the optimal dose for appropriate treatment of enterococcal infections. We investigated the bactericidal activity of daptomycin at various dose exposures compared to that of linezolid against vancomycin-resistant enterococcus (VRE) in an in vitro pharmacokinetic/pharmacodynamic model utilizing simulated endocardial vegetations over 96 h. Daptomycin at doses of 6, 8, 10, and 12 mg/kg of body weight/day and linezolid at a dose of 600 mg every 12 h were evaluated against two clinical vancomycin-resistant Enterococcus faecium strains (EFm11499 and 09-184D1051), one of which was linezolid resistant (09-184D1051), and one clinical vancomycin-resistant Enterococcus faecalis strain (EFs11496). Daptomycin MICs were 4, 2, and 0.5 μg/ml for EFm11499, 09-184D1051, and EFs11496, respectively. Bactericidal activity, defined as a ≥ 3 log(10) CFU/g reduction from the initial colony count, was demonstrated against all three isolates with all doses of daptomycin; however, bactericidal activity was not sustained with the daptomycin 6- and 8-mg/kg/day regimens. Linezolid was bacteriostatic against EFm11499 and displayed no appreciable activity against 09-184D1051 or EFs11496. Concentration-dependent killing was displayed with more sustained reduction in colony count (3.58 to 6.46 and 5.89 to 6.56 log(10) CFU/g) at 96 h for the simulated regimen of daptomycin at doses of 10 and 12 mg/kg/day, respectively (P ≤ 0.012). No E. faecium mutants with reduced susceptibility were recovered at any dosage regimen; however, the E. faecalis strain developed reduced daptomycin susceptibility with daptomycin at 6, 8, and 10 but not at 12 mg/kg/day. Daptomycin displayed a dose-dependent response against three VRE isolates, with high-dose daptomycin producing sustained bactericidal activity. Further research is warranted.
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Vidaillac C, Parra-Ruiz J, Winterfield P, Rybak MJ. In vitro pharmacokinetic/pharmacodynamic activity of NXL103 versus clindamycin and linezolid against clinical Staphylococcus aureus and Streptococcus pyogenes isolates. Int J Antimicrob Agents 2011; 38:301-6. [PMID: 21764263 DOI: 10.1016/j.ijantimicag.2011.04.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Revised: 04/22/2011] [Accepted: 04/27/2011] [Indexed: 01/22/2023]
Abstract
NXL103 (linopristin/flopristin, 30/70) is a novel oral streptogramin combination with activity against a large variety of multidrug-resistant Gram-positive pathogens. The objective of this study was to evaluate the in vitro activity of NXL103 in comparison with oral comparators (clindamycin and linezolid). Six clinical isolates [four meticillin-resistant Staphylococcus aureus (MRSA) and two Streptococcus pyogenes] were exposed for 48 h in an in vitro pharmacokinetic/pharmacodynamic (PK/PD) model at a starting inoculum of ca. 10(6) colony-forming units (CFU)/mL. Antimicrobial simulations included NXL103 500 mg every 12 h, linezolid 600 mg every 12 h and clindamycin 450 mg every 6 h. Bactericidal and static effects were defined as ≥3log(10) and <3log(10) CFU/mL kill from the starting inoculum, respectively. Experiments were performed in duplicate to ensure reproducibility, and differences between regimens were evaluated by analysis of variance (ANOVA) with Tukey's post-hoc test. NXL103 exhibited lower minimum inhibitory concentrations than comparators, with values ≤0.06 mg/L for S. pyogenes and 0.125-0.25 mg/L for MRSA isolates. In the PK/PD model, NXL103 demonstrated significantly better activity than linezolid and clindamycin (P<0.05), achieving sustained bactericidal activity within <2 h against S. pyogenes strains and between 7.3-32 h against MRSA isolates. In contrast, linezolid only exhibited a static effect, whereas clindamycin achieved 3log(10) kill at 6h against the unique clindamycin-susceptible S. pyogenes strain evaluated. In conclusion, at therapeutic concentrations NXL103 exhibits promising activity against both MRSA and S. pyogenes strains, including clindamycin-resistant organisms. Further in vitro and in vivo experiments are warranted to explore the therapeutic benefit of NXL103 for the treatment of Gram-positive skin and soft-tissue infections.
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Affiliation(s)
- Celine Vidaillac
- Anti-Infective Research Laboratory, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI 48201, USA
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In vitro pharmacokinetic/pharmacodynamic models in anti-infective drug development: focus on TB. Future Med Chem 2011; 2:1355-69. [PMID: 21359155 DOI: 10.4155/fmc.10.224] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
For rapid anti-tuberculosis (TB) drug development in vitro pharmacokinetic/pharmacodynamic (PK/PD) models are useful in evaluating the direct interaction between the drug and the bacteria, thereby guiding the selection of candidate compounds and the optimization of their dosing regimens. Utilizing in vivo drug-clearance profiles from animal and/or human studies and simulating them in an in vitro PK/PD model allows the in-depth characterization of antibiotic activity of new and existing antibacterials by generating time–kill data. These data capture the dynamic interplay between mycobacterial growth and changing drug concentration as encountered during prolonged drug therapy. This review focuses on important PK/PD parameters relevant to anti-TB drug development, provides an overview of in vitro PK/PD models used to evaluate the efficacy of agents against mycobacteria and discusses the related mathematical modeling approaches of time–kill data. Overall, it provides an introduction to in vitro PK/PD models and their application as critical tools in evaluating anti-TB drugs.
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Sasaki T, Takane H, Ogawa K, Isagawa S, Hirota T, Higuchi S, Horii T, Otsubo K, Ieiri I. Population pharmacokinetic and pharmacodynamic analysis of linezolid and a hematologic side effect, thrombocytopenia, in Japanese patients. Antimicrob Agents Chemother 2011; 55:1867-73. [PMID: 21357301 PMCID: PMC3088209 DOI: 10.1128/aac.01185-10] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Accepted: 02/13/2011] [Indexed: 12/12/2022] Open
Abstract
Linezolid is an antimicrobial agent to treat infections by Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus (MRSA). While effective, linezolid treatment frequently is associated with hematological side effects, especially thrombocytopenia. However, little is known about the mechanism of this side effect and the exposure-response relationship. The present population pharmacokinetic/pharmacodynamic (PPK/PD) study was undertaken to elucidate the factors that determine linezolid levels, the relationship between exposure to linezolid and a decrease in platelet counts, and appropriate dosage adjustments based on exposure levels. In total, 50 patients (135 plasma samples) were used for the PPK analysis. The PPK analysis revealed that renal function and severe liver cirrhosis (Child Pugh grade C) significantly affect the pharmacokinetics of linezolid according to the equation clearance (liter/h)=2.85×(creatinine clearance/60.9)0.618×0.472CIR (CIR indicates cirrhosis status; 0 for noncirrhosis, 1 for cirrhosis patients). Using 603 platelet counts from 45 patients, a PPK/PD analysis with a semimechanistic pharmacodynamic model described the relationship between linezolid exposure and platelet counts quantitatively, and the newly constructed model was validated using external data (776 platelet counts from 60 patients). Simulation indicated considerable risks in patients with insufficient renal function (creatinine clearance, ≤30 ml/min) or severe liver cirrhosis. For these patients, a reduced dosage (600 mg/day) would be recommended for sufficient efficacy (area under the concentration-time curve over 24 h in the steady state divided by the MIC, >100) and safety.
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Affiliation(s)
- Tomohiro Sasaki
- Department of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Hiroshi Takane
- Department of Hospital Pharmacy, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Katsuhiro Ogawa
- Department of Hospital Pharmacy, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Sayaka Isagawa
- Department of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Takeshi Hirota
- Department of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Shun Higuchi
- Department of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Toshinobu Horii
- Infection Control Division, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Kenji Otsubo
- Department of Hospital Pharmacy, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Ichiro Ieiri
- Department of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
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CREMADES ROSA, RODRÍGUEZ JUANCARLOS, GARCIA-PACHÓN EDUARDO, GALIANA ANTONIO, RUIZ-GARCÍA MONTSERRAT, LÓPEZ PILAR, ROYO GLORIA. Interaction between linezolid and Mycobacterium tuberculosis in an experimental in vitro model. APMIS 2011; 119:304-8. [DOI: 10.1111/j.1600-0463.2011.02735.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Novel daptomycin combinations against daptomycin-nonsusceptible methicillin-resistant Staphylococcus aureus in an in vitro model of simulated endocardial vegetations. Antimicrob Agents Chemother 2010; 54:5187-92. [PMID: 20921318 DOI: 10.1128/aac.00536-10] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Reduced susceptibility to daptomycin has been reported in patients with infections due to methicillin-resistant Staphylococcus aureus (MRSA). Although infections with daptomycin-nonsusceptible (DNS) MRSA are infrequent, optimal therapy of these strains has not been determined. We investigated the killing effects of novel antibiotic combinations with daptomycin (DAP) against two clinical DNS MRSA isolates (SA-684 and R6003) in a 72-h in vitro pharmacokinetic/pharmacodynamic (PK/PD) model with simulated endocardial vegetations (SEV). Simulated regimens included DAP at 6 mg/kg every 24 h (q24h) alone or in combination with trimethoprim-sulfamethoxazole (TMP/SMX) at 160/800 mg q12h, linezolid (LIN) at 600 mg q12h, cefepime (CEF) at 2 g q12h, and nafcillin (NAF) at 4 g q4h. Bactericidal activity was defined as a ≥3-log(10) CFU/g kill. Differences in CFU/g were evaluated between 4 and 72 h by analysis of variance with the Bonferroni post hoc test. DAP MICs were 4 and 2 mg/liter for SA-684 and R6003, respectively. In the PK/PD model, DAP alone was slowly bactericidal, achieving a 3-log(10) kill at 24 and 50 h for SA-684 and R6003, respectively. Against SA-684, DAP plus TMP/SMX, CEF, LIN, or NAF was bactericidal at 4, 4, 8, and 8 h, respectively, and maintained this activity for the 72-h study duration. DAP plus TMP/SMX or CEF exhibited superior killing than DAP alone against SA-684 between 4 and 72 h, and overall this was significant (P < 0.05). Against R6003, DAP plus TMP/SMX was bactericidal (8 h) and superior to DAP alone between 8 and 72 h (P < 0.001). The unique combination of DAP plus TMP/SMX was the most effective and rapidly bactericidal regimen against the two isolates tested and may provide a clinical option to treat DNS S. aureus infections.
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