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Bilal M, Ullah S, Jaehde U, Trueck C, Zaremba D, Wachall B, Wargenau M, Scheidel B, Wiesen MHJ, Gazzaz M, Chen C, Büsker S, Fuhr U, Taubert M, Dokos C. Assessment of body mass-related covariates for rifampicin pharmacokinetics in healthy Caucasian volunteers. Eur J Clin Pharmacol 2024; 80:1271-1283. [PMID: 38722350 PMCID: PMC11303472 DOI: 10.1007/s00228-024-03697-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 04/29/2024] [Indexed: 08/07/2024]
Abstract
PURPOSE Currently, body weight-based dosing of rifampicin is recommended. But lately, fat-free mass (FFM) was reported to be superior to body weight (BW). The present evaluation aimed to assess the influence of body mass-related covariates on rifampicin's pharmacokinetics (PK) parameters in more detail using non-linear mixed effects modeling (NLMEM). METHODS Twenty-four healthy Caucasian volunteers were enrolled in a bioequivalence study, each receiving a test and a reference tablet of 600 mg of rifampicin separated by a wash-out period of at least 9 days. Monolix version 2023R1 was used for NLMEM. Monte Carlo simulations (MCS) were performed to visualize the relationship of body size descriptors to the exposure to rifampicin. RESULTS A one-compartment model with nonlinear (Michaelis-Menten) elimination and zero-order absorption kinetics with a lag time best described the data. The covariate model including fat-free mass (FFM) on volume of distribution (V/F) and on maximum elimination rate (Vmax/F) lowered the objective function value (OFV) by 56.4. The second-best covariate model of sex on V/F and Vmax/F and BW on V/F reduced the OFV by 51.2. The decrease in unexplained inter-individual variability on Vmax/F in both covariate models was similar. For a given dose, MCS showed lower exposure to rifampicin with higher FFM and accordingly in males compared to females with the same BW and body height. CONCLUSION Our results indicate that beyond BW, body composition as reflected by FFM could also be relevant for optimized dosing of rifampicin. This assumption needs to be studied further in patients treated with rifampicin.
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Affiliation(s)
- Muhammad Bilal
- Department I of Pharmacology, Center for Pharmacology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.
- Department of Clinical Pharmacy, Institute of Pharmacy, University of Bonn, Bonn, Germany.
| | - Sami Ullah
- Department I of Pharmacology, Center for Pharmacology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Ulrich Jaehde
- Department of Clinical Pharmacy, Institute of Pharmacy, University of Bonn, Bonn, Germany
| | - Christina Trueck
- Department I of Pharmacology, Center for Pharmacology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Dario Zaremba
- Department I of Pharmacology, Center for Pharmacology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Bertil Wachall
- InfectoPharm Arzneimittel Und Consilium GmbH, 64646, Heppenheim, Germany
| | | | | | - Martin H J Wiesen
- Pharmacology at the Laboratory Diagnostics Centre, Faculty of Medicine, University Hospital Cologne, University of Cologne, Therapeutic Drug Monitoring, Cologne, Germany
| | - Malaz Gazzaz
- Pharmaceutical Practices Department, College of Pharmacy, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Chunli Chen
- Department I of Pharmacology, Center for Pharmacology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Heilongjiang Key Laboratory for Animal Disease Control and Pharmaceutical Development, College of Veterinary Medicine, Northeast Agricultural University, 600 Changjiang Road, Xiangfang District, Harbin, 150030, People's Republic of China
| | - Sören Büsker
- Department I of Pharmacology, Center for Pharmacology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Uwe Fuhr
- Department I of Pharmacology, Center for Pharmacology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Max Taubert
- Department I of Pharmacology, Center for Pharmacology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Charalambos Dokos
- Department I of Pharmacology, Center for Pharmacology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
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Verma R, da Silva KE, Rockwood N, Wasmann RE, Yende N, Song T, Kim E, Denti P, Wilkinson RJ, Andrews JR. A Nanopore Sequencing-based Pharmacogenomic Panel to Personalize Tuberculosis Drug Dosing. Am J Respir Crit Care Med 2024; 209:1486-1496. [PMID: 38647526 PMCID: PMC11208962 DOI: 10.1164/rccm.202309-1583oc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 03/04/2024] [Indexed: 04/25/2024] Open
Abstract
Rationale: Standardized dosing of antitubercular drugs leads to variable plasma drug levels, which are associated with adverse drug reactions, delayed treatment response, and relapse. Mutations in genes affecting drug metabolism explain considerable interindividual pharmacokinetic variability; however, pharmacogenomic assays that predict metabolism of antitubercular drugs have been lacking. Objectives: We sought to develop a Nanopore sequencing panel and validate its performance in patients with active tuberculosis (TB) to personalize treatment dosing. Methods: We developed a Nanopore sequencing panel targeting 15 SNPs in five genes affecting the metabolism of antitubercular drugs. For validation, we sequenced DNA samples (n = 48) from the 1,000 Genomes Project and compared the variant calling accuracy with that of Illumina genome sequencing. We then sequenced DNA samples from patients with active TB (n = 100) from South Africa on a MinION Mk1C and evaluated the relationship between genotypes and pharmacokinetic parameters for isoniazid (INH) and rifampin (RIF). Measurements and Main Results: The pharmacogenomic panel achieved 100% concordance with Illumina sequencing in variant identification for the samples from the 1,000 Genomes Project. In the clinical cohort, coverage was more than 100× for 1,498 of 1,500 (99.8%) amplicons across the 100 samples. Thirty-three percent, 47%, and 20% of participants were identified as slow, intermediate, and rapid INH acetylators, respectively. INH clearance was 2.2 times higher among intermediate acetylators and 3.8 times higher among rapid acetylators, compared with slow acetylators (P < 0.0001). RIF clearance was 17.3% (2.50-29.9) lower in individuals with homozygous AADAC rs1803155 G→A substitutions (P = 0.0015). Conclusions: Targeted sequencing can enable the detection of polymorphisms that influence TB drug metabolism on a low-cost, portable instrument to personalize dosing for TB treatment or prevention.
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Affiliation(s)
- Renu Verma
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California
- Manipal Academy of Higher Education, Manipal, India
- Institute of Bioinformatics, International Tech Park, Bangalore, India
| | - Kesia Esther da Silva
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California
| | - Neesha Rockwood
- Wellcome Center for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine and Department Medicine
- Department of Infectious Diseases, Imperial College, London, United Kingdom
- Department of Medical Microbiology and Immunology, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka; and
| | - Roeland E. Wasmann
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Nombuso Yende
- Department of Pathology and Institute of Infectious Disease and Molecular Medicine, and
| | - Taeksun Song
- Department of Pathology and Institute of Infectious Disease and Molecular Medicine, and
| | - Eugene Kim
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Robert J. Wilkinson
- Wellcome Center for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine and Department Medicine
- Department of Infectious Diseases, Imperial College, London, United Kingdom
- Francis Crick Institute, London, United Kingdom
| | - Jason R. Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California
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Abdelgawad N, Chirehwa M, Schutz C, Barr D, Ward A, Janssen S, Burton R, Wilkinson RJ, Shey M, Wiesner L, McIlleron H, Maartens G, Meintjes G, Denti P. Pharmacokinetics of antitubercular drugs in patients hospitalized with HIV-associated tuberculosis: a population modeling analysis. Wellcome Open Res 2024; 7:72. [PMID: 37008250 PMCID: PMC10050909 DOI: 10.12688/wellcomeopenres.17660.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2024] [Indexed: 03/05/2024] Open
Abstract
Background Early mortality among hospitalized HIV-associated tuberculosis (TB/HIV) patients is high despite treatment. The pharmacokinetics of rifampicin, isoniazid, and pyrazinamide were investigated in hospitalized TB/HIV patients and a cohort of outpatients with TB (with or without HIV) to determine whether drug exposures differed between groups. Methods Standard first-line TB treatment was given daily as per national guidelines, which consisted of oral 4-drug fixed-dose combination tablets containing 150 mg rifampicin, 75 mg isoniazid, 400 mg pyrazinamide, and 275 mg ethambutol. Plasma samples were drawn on the 3rd day of treatment over eight hours post-dose. Rifampicin, isoniazid, and pyrazinamide in plasma were quantified and NONMEM ® was used to analyze the data. Results Data from 60 hospitalized patients (11 of whom died within 12 weeks of starting treatment) and 48 outpatients were available. Median (range) weight and age were 56 (35 - 88) kg, and 37 (19 - 77) years, respectively. Bioavailability and clearance of the three drugs were similar between TB/HIV hospitalized and TB outpatients. However, rifampicin's absorption was slower in hospitalized patients than in outpatients; mean absorption time was 49.9% and 154% more in hospitalized survivors and hospitalized deaths, respectively, than in outpatients. Higher levels of conjugated bilirubin correlated with lower rifampicin clearance. Isoniazid's clearance estimates were 25.5 L/h for fast metabolizers and 9.76 L/h for slow metabolizers. Pyrazinamide's clearance was more variable among hospitalized patients. The variability in clearance among patients was 1.70 and 3.56 times more for hospitalized survivors and hospitalized deaths, respectively, than outpatients. Conclusions We showed that the pharmacokinetics of first-line TB drugs are not substantially different between hospitalized TB/HIV patients and TB (with or without HIV) outpatients. Hospitalized patients do not seem to be underexposed compared to their outpatient counterparts, as well as hospitalized patients who survived vs who died within 12 weeks of hospitalization.
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Affiliation(s)
- Noha Abdelgawad
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Maxwell Chirehwa
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Charlotte Schutz
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
- Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - David Barr
- Wellcome Trust Liverpool Glasgow Centre for Global Health Research, University of Liverpool, Liverpool, L3 5QA, UK
| | - Amy Ward
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
- Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Saskia Janssen
- Amsterdam University Medical Centre, University of Amsterdam, Amsterdam, 19268, The Netherlands
| | - Rosie Burton
- Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
- Khayelitsha Hospital, Department of Medicine, Khayelitsha, 7784, South Africa
| | - Robert J. Wilkinson
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
- Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
- Department of Infectious Diseases, Imperial College London, London, W12 0NN, UK
- The Francis Crick Institute, London, NW1 1AT, UK
| | - Muki Shey
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Lubbe Wiesner
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Helen McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Gary Maartens
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Graeme Meintjes
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
- Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
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Hoa PQ, Kim HK, Jang TW, Seo H, Oh JY, Kim HC, Shin AY, Min J, Jayanti RP, Hung TM, Anh NK, Ahn S, Long NP, Cho YS, Shin JG. Population pharmacokinetic model of rifampicin for personalized tuberculosis pharmacotherapy: Effects of SLCO1B1 polymorphisms on drug exposure. Int J Antimicrob Agents 2024; 63:107034. [PMID: 37977236 DOI: 10.1016/j.ijantimicag.2023.107034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 09/27/2023] [Accepted: 11/09/2023] [Indexed: 11/19/2023]
Abstract
BACKGROUND Rifampicin (RIF) exhibits high pharmacokinetic (PK) variability among individuals; a low plasma concentration might result in unfavorable treatment outcomes and drug resistance. This study evaluated the contributions of non- and genetic factors to the interindividual variability of RIF exposure, then suggested initial doses for patients with different weight bands. METHODS This multicenter prospective cohort study in Korea analyzed demographic and clinical data, the solute carrier organic anion transporter family member 1B1 (SLCO1B1) genotypes, and RIF concentrations. Population PK modeling and simulations were conducted using nonlinear mixed-effect modeling. RESULTS In total, 879 tuberculosis (TB) patients were divided into a training dataset (510 patients) and a test dataset (359 patients). A one-compartment model with allometric scaling for effect of body size best described the RIF PKs. The apparent clearance (CL/F) was 16.6% higher among patients in the SLCO1B1 rs4149056 wild-type group than among patients in variant group, significantly decreasing RIF exposure in the wild-type group. The developed model showed better predictive performance compared with previously reported models. We also suggested that patients with body weights of <40 kg, 40-55 kg, 55-70 kg, and >70 kg patients receive RIF doses of 450, 600, 750, and 1050 mg/day, respectively. CONCLUSIONS Total body weight and SLCO1B1 rs4149056 genotypes were the most significant covariates that affected RIF CL/F variability in Korean TB patients. We suggest initial doses of RIF based on World Health Organization weight-band classifications. The model may be implemented in treatment monitoring for TB patients.
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Affiliation(s)
- Pham Quang Hoa
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea; Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Hyun Kuk Kim
- Department of Internal Medicine, Division of Pulmonology, Inje University Haeundae Paik Hospital, Busan, Republic of Korea
| | - Tae Won Jang
- Department of Internal Medicine, Pulmonary Division, Kosin University Gospel Hospital, Busan, Republic of Korea
| | - Hyewon Seo
- Department of Internal Medicine, Division of Pulmonary Medicine, Kyungpook National University Hospital, Daegu, Republic of Korea
| | - Jee Youn Oh
- Department of Internal Medicine, Division of Pulmonology, Korea University Guro Hospital, Seoul, Republic of Korea
| | - Ho Cheol Kim
- Department of Internal Medicine, Gyeongsang National University Changwon Hospital, Gyeongsang National University School of Medicine, Changwon, Republic of Korea
| | - Ah Young Shin
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, Incheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jinsoo Min
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Rannissa Puspita Jayanti
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea; Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Tran Minh Hung
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea; Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Nguyen Ky Anh
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea; Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Sangzin Ahn
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea; Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Nguyen Phuoc Long
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea; Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Yong-Soon Cho
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea; Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea.
| | - Jae-Gook Shin
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea; Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea; Department of Clinical Pharmacology, Inje University Busan Paik Hospital, Busan, Republic of Korea.
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Asif M, Qusty NF, Alghamdi S. An Overview of Various Rifampicin Analogs against Mycobacterium tuberculosis and their Drug Interactions. Med Chem 2024; 20:268-292. [PMID: 37855280 DOI: 10.2174/0115734064260853230926080134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 07/14/2023] [Accepted: 08/12/2023] [Indexed: 10/20/2023]
Abstract
The success of the TB control program is hampered by the major issue of drug-resistant tuberculosis (DR-TB). The situation has undoubtedly been made more difficult by the widespread and multidrug-resistant (XDR) strains of TB. The modification of existing anti-TB medications to produce derivatives that can function on resistant TB bacilli is one of the potential techniques to overcome drug resistance affordably and straightforwardly. In comparison to novel pharmaceuticals for drug research and progress, these may have a better half-life and greater bioavailability, be more efficient, and serve as inexpensive alternatives. Mycobacterium tuberculosis, which is drugsusceptible or drug-resistant, is effectively treated by several already prescribed medications and their derivatives. Due to this, the current review attempts to give a brief overview of the rifampicin derivatives that can overcome the parent drug's resistance and could, hence, act as useful substitutes. It has been found that one-third of the global population is affected by M. tuberculosis. The most common cause of infection-related death can range from latent TB to TB illness. Antibiotics in the rifamycin class, including rifampicin or rifampin (RIF), rifapentine (RPT), and others, have a special sterilizing effect on M. tuberculosis. We examine research focused on evaluating the safety, effectiveness, pharmacokinetics, pharmacodynamics, risk of medication interactions, and other characteristics of RIF analogs. Drug interactions are especially difficult with RIF because it must be taken every day for four months to treat latent TB infection. RIF continues to be the gold standard of treatment for drug-sensitive TB illness. RIF's safety profile is well known, and the two medicines' adverse reactions have varying degrees of frequency. The authorized once-weekly RPT regimen is insufficient, but greater dosages of either medication may reduce the amount of time needed to treat TB effectively.
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Affiliation(s)
- Mohammad Asif
- Department of Pharmaceutical Chemistry, Era College of Pharmacy, Era University, Lucknow, 226003, Uttar Pradesh, India
| | - Naeem F Qusty
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al‒Qura University, Makkah, 21955, Saudi Arabia
| | - Saad Alghamdi
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al‒Qura University, Makkah, 21955, Saudi Arabia
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Galileya LT, Wasmann RE, Chabala C, Rabie H, Lee J, Njahira Mukui I, Hesseling A, Zar H, Aarnoutse R, Turkova A, Gibb D, Cotton MF, McIlleron H, Denti P. Evaluating pediatric tuberculosis dosing guidelines: A model-based individual data pooled analysis. PLoS Med 2023; 20:e1004303. [PMID: 37988391 PMCID: PMC10662720 DOI: 10.1371/journal.pmed.1004303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 10/02/2023] [Indexed: 11/23/2023] Open
Abstract
BACKGROUND The current World Health Organization (WHO) pediatric tuberculosis dosing guidelines lead to suboptimal drug exposures. Identifying factors altering the exposure of these drugs in children is essential for dose optimization. Pediatric pharmacokinetic studies are usually small, leading to high variability and uncertainty in pharmacokinetic results between studies. We pooled data from large pharmacokinetic studies to identify key covariates influencing drug exposure to optimize tuberculosis dosing in children. METHODS AND FINDINGS We used nonlinear mixed-effects modeling to characterize the pharmacokinetics of rifampicin, isoniazid, and pyrazinamide, and investigated the association of human immunodeficiency virus (HIV), antiretroviral therapy (ART), drug formulation, age, and body size with their pharmacokinetics. Data from 387 children from South Africa, Zambia, Malawi, and India were available for analysis; 47% were female and 39% living with HIV (95% on ART). Median (range) age was 2.2 (0.2 to 15.0) years and weight 10.9 (3.2 to 59.3) kg. Body size (allometry) was used to scale clearance and volume of distribution of all 3 drugs. Age affected the bioavailability of rifampicin and isoniazid; at birth, children had 48.9% (95% confidence interval (CI) [36.0%, 61.8%]; p < 0.001) and 64.5% (95% CI [52.1%, 78.9%]; p < 0.001) of adult rifampicin and isoniazid bioavailability, respectively, and reached full adult bioavailability after 2 years of age for both drugs. Age also affected the clearance of all drugs (maturation), children reached 50% adult drug clearing capacity at around 3 months after birth and neared full maturation around 3 years of age. While HIV per se did not affect the pharmacokinetics of first-line tuberculosis drugs, rifampicin clearance was 22% lower (95% CI [13%, 28%]; p < 0.001) and pyrazinamide clearance was 49% higher (95% CI [39%, 57%]; p < 0.001) in children on lopinavir/ritonavir; isoniazid bioavailability was reduced by 39% (95% CI [32%, 45%]; p < 0.001) when simultaneously coadministered with lopinavir/ritonavir and was 37% lower (95% CI [22%, 52%]; p < 0.001) in children on efavirenz. Simulations of 2010 WHO-recommended pediatric tuberculosis doses revealed that, compared to adult values, rifampicin exposures are lower in most children, except those younger than 3 months, who experience relatively higher exposure for all drugs, due to immature clearance. Increasing the rifampicin doses in children older than 3 months by 75 mg for children weighing <25 kg and 150 mg for children weighing >25 kg could improve rifampicin exposures. Our analysis was limited by the differences in availability of covariates among the pooled studies. CONCLUSIONS Children older than 3 months have lower rifampicin exposures than adults and increasing their dose by 75 or 150 mg could improve therapy. Altered exposures in children with HIV is most likely caused by concomitant ART and not HIV per se. The importance of the drug-drug interactions with lopinavir/ritonavir and efavirenz should be evaluated further and considered in future dosing guidance. TRIAL REGISTRATION ClinicalTrials.gov registration numbers; NCT02348177, NCT01637558, ISRCTN63579542.
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Affiliation(s)
- Lufina Tsirizani Galileya
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
- Training and Research Unit of Excellence, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Roeland E. Wasmann
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Chishala Chabala
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
- Department of Pediatrics, University of Zambia, School of Medicine, Lusaka, Zambia
- University Teaching Hospitals-Children’s Hospital, Lusaka, Zambia
| | - Helena Rabie
- Department of Pediatrics and Child Health and Family Center for Research with Ubuntu, Stellenbosch University, Cape Town, South Africa
| | - Janice Lee
- Drugs for Neglected Diseases initiative, Geneva, Switzerland
| | | | - Anneke Hesseling
- Desmond Tutu TB Centre, Department of Pediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Heather Zar
- Department of Pediatrics and Child Health, Red Cross War Memorial Children’s Hospital, and SA-MRC Unit on Child & Adolescent Health, University of Cape Town, Cape Town, South Africa
| | - Rob Aarnoutse
- Radboud University Medical Center, Nijmegen, the Netherlands
| | - Anna Turkova
- Medical Research Council Clinical Trials Unit at University College London, Institute of Clinical Trials and Methodology, London, United Kingdom
| | - Diana Gibb
- Medical Research Council Clinical Trials Unit at University College London, Institute of Clinical Trials and Methodology, London, United Kingdom
| | - Mark F. Cotton
- Department of Pediatrics and Child Health and Family Center for Research with Ubuntu, Stellenbosch University, Cape Town, South Africa
| | - Helen McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
- Wellcome Centre for Infectious Diseases Research in Africa (CIDRI-Africa), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
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7
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Verma R, da Silva KE, Rockwood N, Wasmann RE, Yende N, Song T, Kim E, Denti P, Wilkinson RJ, Andrews JR. A Nanopore sequencing-based pharmacogenomic panel to personalize tuberculosis drug dosing. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.09.08.23295248. [PMID: 37732197 PMCID: PMC10508808 DOI: 10.1101/2023.09.08.23295248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
Rationale Standardized dosing of anti-tubercular (TB) drugs leads to variable plasma drug levels, which are associated with adverse drug reactions, delayed treatment response, and relapse. Mutations in genes affecting drug metabolism explain considerable interindividual pharmacokinetic variability; however, pharmacogenomic (PGx) assays that predict metabolism of anti-TB drugs have been lacking. Objectives To develop a Nanopore sequencing panel and validate its performance in active TB patients to personalize treatment dosing. Measurements and Main Results We developed a Nanopore sequencing panel targeting 15 single nucleotide polymorphisms (SNP) in 5 genes affecting the metabolism of isoniazid (INH), rifampin (RIF), linezolid and bedaquiline. For validation, we sequenced DNA samples (n=48) from the 1000 genomes project and compared variant calling accuracy with Illumina genome sequencing. We then sequenced DNA samples from patients with active TB (n=100) from South Africa on a MinION Mk1C and evaluated the relationship between genotypes and pharmacokinetic parameters for INH and RIF. Results The PGx panel achieved 100% concordance with Illumina sequencing in variant identification for the samples from the 1000 Genomes Project. In the clinical cohort, coverage was >100x for 1498/1500 (99.8%) amplicons across the 100 samples. One third (33%) of participants were identified as slow, 47% were intermediate and 20% were rapid isoniazid acetylators. Isoniazid clearance was significantly impacted by acetylator status (p<0.0001) with median (IQR) clearances of 11.2 L/h (9.3-13.4), 27.2 L/h (22.0-31.7), and 45.1 L/h (34.1-51.1) in slow, intermediate, and rapid acetylators. Rifampin clearance was 17.3% (2.50-29.9) lower in individuals with homozygous AADAC rs1803155 G>A substitutions (p=0.0015). Conclusion Targeted sequencing can enable detection of polymorphisms influencing TB drug metabolism on a low-cost, portable instrument to personalize dosing for TB treatment or prevention.
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Affiliation(s)
- Renu Verma
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, California, USA
- Institute of Bioinformatics, International Tech Park, Bangalore, India
- Manipal Academy of Higher Education (MAHE), Manipal, Karnataka, India
| | - Kesia Esther da Silva
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, California, USA
| | - Neesha Rockwood
- Center for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine and Dept. Medicine, University of Cape Town, Observatory 7925, South Africa
- Department of Infectious Diseases, Imperial College, London, W12 0NN, United Kingdom
- Department of Medical Microbiology and Immunology, Faculty of Medicine, University of Colombo, Sri Lanka
| | - Roeland E. Wasmann
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Nombuso Yende
- Department of Pathology and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Taeksun Song
- Department of Pathology and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Eugene Kim
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, California, USA
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Robert. J. Wilkinson
- Center for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine and Dept. Medicine, University of Cape Town, Observatory 7925, South Africa
- Department of Infectious Diseases, Imperial College, London, W12 0NN, United Kingdom
- Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Jason R. Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, California, USA
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Chen RH, Michael T, Kuhlin J, Schön T, Stocker S, Alffenaar JWC. Is there a need to optimise pyrazinamide doses in patients with tuberculosis? A systematic review. Int J Antimicrob Agents 2023; 62:106914. [PMID: 37419292 DOI: 10.1016/j.ijantimicag.2023.106914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 06/09/2023] [Accepted: 06/30/2023] [Indexed: 07/09/2023]
Abstract
Pyrazinamide (PZA) is a first-line antituberculosis drug with potent sterilising activity. Variability in drug exposure may translate into suboptimal treatment responses. This systematic review, conducted according to PRISMA guidelines, aimed to evaluate the concentration-effect relationship. In vitro/in vivo studies had to contain information on the infection model, PZA dose and concentration, and microbiological outcome. Human studies had to present information on PZA dose, measures of drug exposure and maximum concentration, and microbiological response parameter or overall treatment outcome. A total of 34 studies were assessed, including in vitro (n = 2), in vivo (n = 3) and clinical studies (n = 29). Intracellular and extracellular models demonstrated a direct correlation between PZA dose of 15-50 mg/kg/day and reduction in bacterial count between 0.50-27.7 log10 CFU/mL. Consistent with this, higher PZA doses (>150 mg/kg) were associated with a greater reduction in bacterial burden in BALB/c mice models. Human pharmacokinetic studies displayed a linear positive correlation between PZA dose (i.e. 21.4-35.7 mg/kg/day) and drug exposure (AUC range 220.6-514.5 mg·h/L). Additionally, human studies confirmed a dose-effect relationship, with an increased 2-month sputum culture conversion rate at AUC/MIC targets of 8.4-11.3 with higher exposure/susceptibility ratios leading to greater efficacy. A 5-fold variability in AUC was observed at PZA dose of 25 mg/kg. A direct concentration-effect relationship and increased treatment efficacy with higher PZA exposure to susceptibility ratios was observed. Taking into account variability in drug exposure and treatment response, further studies on dose optimisation are justified.
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Affiliation(s)
- Ricky Hao Chen
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Toni Michael
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Johanna Kuhlin
- Karolinska Institutet, Department of Medicine Solna, Division of Infectious Diseases, Stockholm, Sweden; Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Thomas Schön
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden; Department of Infectious Diseases, Linköping University Hospital, Linköping, Sweden; Department of Infectious Diseases, Kalmar County Hospital, Linköping University, Kalmar, Sweden
| | - Sophie Stocker
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia; Department of Clinical Pharmacology & Toxicology, St Vincent's Hospital, Sydney, NSW, Australia; School of Clinical Medicine, St Vincent's Healthcare Clinical Campus, Faculty of Medicine and Health, The University of New South Wales, Sydney, NSW, Australia; Sydney Institute for Infectious Diseases, University of Sydney, Sydney, NSW, Australia
| | - Jan-Willem C Alffenaar
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia; Westmead Hospital, Sydney, NSW, Australia; Sydney Institute for Infectious Diseases, University of Sydney, Sydney, NSW, Australia.
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9
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Kim R, Jayanti RP, Lee H, Kim HK, Kang J, Park IN, Kim J, Oh JY, Kim HW, Lee H, Ghim JL, Ahn S, Long NP, Cho YS, Shin JG. Development of a population pharmacokinetic model of pyrazinamide to guide personalized therapy: impacts of geriatric and diabetes mellitus on clearance. Front Pharmacol 2023; 14:1116226. [PMID: 37305528 PMCID: PMC10250603 DOI: 10.3389/fphar.2023.1116226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 04/19/2023] [Indexed: 06/13/2023] Open
Abstract
Objectives: This study was performed to develop a population pharmacokinetic model of pyrazinamide for Korean tuberculosis (TB) patients and to explore and identify the influence of demographic and clinical factors, especially geriatric diabetes mellitus (DM), on the pharmacokinetics (PK) of pyrazinamide (PZA). Methods: PZA concentrations at random post-dose points, demographic characteristics, and clinical information were collected in a multicenter prospective TB cohort study from 18 hospitals in Korea. Data obtained from 610 TB patients were divided into training and test datasets at a 4:1 ratio. A population PK model was developed using a nonlinear mixed-effects method. Results: A one-compartment model with allometric scaling for body size effect adequately described the PK of PZA. Geriatric patients with DM (age >70 years) were identified as a significant covariate, increasing the apparent clearance of PZA by 30% (geriatric patients with DM: 5.73 L/h; others: 4.50 L/h), thereby decreasing the area under the concentration-time curve from 0 to 24 h by a similar degree compared with other patients (geriatric patients with DM: 99.87 μg h/mL; others: 132.3 μg h/mL). Our model was externally evaluated using the test set and provided better predictive performance compared with the previously published model. Conclusion: The established population PK model sufficiently described the PK of PZA in Korean TB patients. Our model will be useful in therapeutic drug monitoring to provide dose optimization of PZA, particularly for geriatric patients with DM and TB.
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Affiliation(s)
- Ryunha Kim
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea
- Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Rannissa Puspita Jayanti
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea
- Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Hongyeul Lee
- Division of Pulmonary, Critical Care Medicine, Department of Internal Medicine, Inje University College of Medicine, Busan Paik Hospital, Busan, Republic of Korea
| | - Hyun-Kuk Kim
- Division of Pulmonology, Department of Internal Medicine, Inje University Haeundae Paik Hospital, Busan, Republic of Korea
| | - Jiyeon Kang
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Inje University Ilsan Paik Hospital, Goyang-si, Republic of Korea
| | - I-Nae Park
- Department of Internal Medicine, Inje University Seoul Paik Hospital, Inje University College of Medicine, Seoul, Republic of Korea
| | - Jehun Kim
- Pulmonary Division, Department of IM, Kosin University Gospel Hospital, Busan, Republic of Korea
| | - Jee Youn Oh
- Division of Pulmonology, Department of Internal Medicine, Korea University Guro Hospital, Seoul, Republic of Korea
| | - Hyung Woo Kim
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Incheon St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Incheon, Republic of Korea
| | - Heayon Lee
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Internal Medicine, Eunpyeong St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jong-Lyul Ghim
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea
- Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Sangzin Ahn
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea
- Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Nguyen Phuoc Long
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea
- Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Yong-Soon Cho
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea
- Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
| | - Jae-Gook Shin
- Center for Personalized Precision Medicine of Tuberculosis, Inje University College of Medicine, Busan, Republic of Korea
- Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan, Republic of Korea
- Department of Clinical Pharmacology, Inje University Busan Paik Hospital, Busan, Republic of Korea
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Li J, Cai X, Chen Y, Wang C, Jiao Z. Parametric population pharmacokinetics of isoniazid: a systematic review. Expert Rev Clin Pharmacol 2023; 16:467-489. [PMID: 36971782 DOI: 10.1080/17512433.2023.2196401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
INTRODUCTION Isoniazid (INH) plays an important role in prevention and treatment of tuberculosis (TB). However, large pharmacokinetic (PK) variations are observed in patients receiving standard INH dosages. Considering the influence of PK variations on INH efficacy or adverse reactions, we reviewed the population PK studies of INH and explored significant covariates that influence INH PK. METHODS The PubMed and Embase databases were systematically searched from their inception to 30 January 2023. PPK studies on INH using a parametric nonlinear mixed-effect approach were included in this review. The characteristics and identified significant covariates of the included studies were summarized. RESULTS Twenty-one studies conducted in adults, and seven in pediatrics were included. A two-compartment model with first-order absorption and elimination was the frequently used structural model for INH. NAT2 genotype, body size, and age were identified as significant covariates affecting INH PK variation. The median clearance (CL) value in the fast metabolizers was 2.55-fold higher than that in the slow metabolizers. Infants and children had higher CL per weight values than adults with the same metabolic phenotype. In pediatric patients, CL value increased with postnatal age. CONCLUSIONS Compared with slow metabolizers, the daily dose of INH should be increased by 200-600 mg in fast metabolizers. To achieve effective treatment, pediatric patients need a higher dose per kilogram than adults. Further PPK studies of anti-tuberculosis drugs are needed to comprehensively understand the covariates that affect their PK characteristics and to achieve accurate dose adjustments.
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Abdelgawad N, Chirehwa M, Schutz C, Barr D, Ward A, Janssen S, Burton R, Wilkinson RJ, Shey M, Wiesner L, McIlleron H, Maartens G, Meintjes G, Denti P. Pharmacokinetics of antitubercular drugs in patients hospitalized with HIV-associated tuberculosis: a population modeling analysis. Wellcome Open Res 2022; 7:72. [PMID: 37008250 PMCID: PMC10050909 DOI: 10.12688/wellcomeopenres.17660.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/03/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Early mortality among hospitalized HIV-associated tuberculosis (TB/HIV) patients is high despite treatment. The pharmacokinetics of rifampicin, isoniazid, and pyrazinamide were investigated in hospitalized TB/HIV patients and a cohort of outpatients with TB (with or without HIV) to determine whether drug exposures differed between groups. METHODS Standard first-line TB treatment was given daily as per national guidelines, which consisted of oral 4-drug fixed-dose combination tablets containing 150 mg rifampicin, 75 mg isoniazid, 400 mg pyrazinamide, and 275 mg ethambutol. Plasma samples were drawn on the 3rd day of treatment over eight hours post-dose. Rifampicin, isoniazid, and pyrazinamide in plasma were quantified and NONMEM ® was used to analyze the data. RESULTS Data from 60 hospitalized patients (11 of whom died within 12 weeks of starting treatment) and 48 outpatients were available. Median (range) weight and age were 56 (35 - 88) kg, and 37 (19 - 77) years, respectively. Bioavailability and clearance of the three drugs were similar between TB/HIV hospitalized and TB outpatients. However, rifampicin's absorption was slower in hospitalized patients than in outpatients; mean absorption time was 49.9% and 154% more in hospitalized survivors and hospitalized deaths, respectively, than in outpatients. Higher levels of conjugated bilirubin correlated with lower rifampicin clearance. Isoniazid's clearance estimates were 25.5 L/h for fast metabolizers and 9.76 L/h for slow metabolizers. Pyrazinamide's clearance was more variable among hospitalized patients. The variability in clearance among patients was 1.70 and 3.56 times more for hospitalized survivors and hospitalized deaths, respectively, than outpatients. Conclusion. We showed that the pharmacokinetics of first-line TB drugs are not substantially different between hospitalized TB/HIV patients and TB (with or without HIV) outpatients. Hospitalized patients do not seem to be underexposed compared to their outpatient counterparts, as well as hospitalized patients who survived vs who died within 12 weeks of hospitalization.
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Affiliation(s)
- Noha Abdelgawad
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Maxwell Chirehwa
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Charlotte Schutz
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
- Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - David Barr
- Wellcome Trust Liverpool Glasgow Centre for Global Health Research, University of Liverpool, Liverpool, L3 5QA, UK
| | - Amy Ward
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
- Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Saskia Janssen
- Amsterdam University Medical Centre, University of Amsterdam, Amsterdam, 19268, The Netherlands
| | - Rosie Burton
- Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
- Khayelitsha Hospital, Department of Medicine, Khayelitsha, 7784, South Africa
| | - Robert J. Wilkinson
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
- Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
- Department of Infectious Diseases, Imperial College London, London, W12 0NN, UK
- The Francis Crick Institute, London, NW1 1AT, UK
| | - Muki Shey
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Lubbe Wiesner
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Helen McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Gary Maartens
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Graeme Meintjes
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
- Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
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Population Pharmacokinetic Modelling and Limited Sampling Strategies for Therapeutic Drug Monitoring of Pyrazinamide in Patients with Tuberculosis. Antimicrob Agents Chemother 2022; 66:e0000322. [PMID: 35727060 DOI: 10.1128/aac.00003-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pyrazinamide is one of the first-line antituberculosis drugs. The efficacy of pyrazinamide is associated with the ratio of 24-h area under the concentration-time curve (AUC24) to MIC. The objective of this study was to develop and validate a limited sampling strategy (LSS) based on a population pharmacokinetic (popPK) model to predict AUC24. A popPK model was developed using an iterative two-stage Bayesian procedure and was externally validated. Using data from 20 treatment-naive adult tuberculosis (TB) patients, a one compartment model with transit absorption and first-order elimination best described pyrazinamide pharmacokinetics and fed state was the only significant covariate for absorption rate constant (ka). External validation, using data from 26 TB patients, showed that the popPK model predicted AUC24 with a slight underestimation of 2.1%. LSS were calculated using Monte Carlo simulation (n = 10,000). External validation showed LSS with time points 0 h, 2 h, and 6 h performed best with RMSE of 9.90% and bias of 0.06%. Food slowed absorption of pyrazinamide, but did not affect bioavailability, which may be advantageous in case of nausea or vomiting in which food can be used to diminish these effects. In this study, we successfully developed and validated a popPK model and LSS, using 0 h, 2 h, and 6 h postdose samples, that could be used to perform therapeutic drug monitoring (TDM) of pyrazinamide in TB patients.
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13
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The Effect of Rifampicin on Darunavir, Ritonavir, and Dolutegravir Exposure within Peripheral Blood Mononuclear Cells: a Dose Escalation Study. Antimicrob Agents Chemother 2022; 66:e0013622. [PMID: 35583344 PMCID: PMC9211429 DOI: 10.1128/aac.00136-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ritonavir-boosted darunavir (DRV/r) and dolutegravir (DTG) are affected by induction of metabolizing enzymes and efflux transporters caused by rifampicin (RIF). This complicates the treatment of people living with HIV (PLWH) diagnosed with tuberculosis. Recent data showed that doubling DRV/r dose did not compensate for this effect, and hepatic safety was unsatisfactory. We aimed to evaluate the pharmacokinetics of DRV, ritonavir (RTV), and DTG in the presence and absence of RIF in peripheral blood mononuclear cells (PBMCs). PLWH were enrolled in a dose-escalation crossover study with 6 treatment periods of 7 days. Participants started with DRV/r 800/100 mg once daily (QD), RIF and DTG were added before the RTV dose was doubled, and then they received DRV/r 800/100 twice daily (BD) and then 1,600/200 QD or vice versa. Finally, RIF was withdrawn. Plasma and intra-PBMC drug concentrations were measured through validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. Seventeen participants were enrolled but only 4 completed all study phases due to high incidence of liver toxicity. Intra-PBMC DRV trough serum concentration (Ctrough) after the addition of RIF dropped from a median (interquartile range [IQR]) starting value of 261 ng/mL (158 to 577) to 112 ng/mL (18 to 820) and 31 ng/mL (12 to 331) for 800/100 BD and 1,600/200 QD DRV/r doses, respectively. The DRV intra-PBMC/plasma ratio increased significantly (P = 0.003). DTG and RIF intra-PBMC concentrations were in accordance with previous reports in the absence of RIF or DRV/r. This study showed a differential impact of enzyme and/or transporter induction on DRV/r concentrations in plasma and PBMCs, highlighting the usefulness of studying intra-PBMC pharmacokinetics with drug-drug interactions. (This study has been registered at ClinicalTrials.gov under registration no. NCT03892161.)
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14
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Nardotto GHB, Bollela VR, Rocha A, Della Pasqua O, Lanchote VL. No implication of HIV coinfection on the plasma exposure to rifampicin, pyrazinamide, and ethambutol in tuberculosis patients. Clin Transl Sci 2021; 15:514-523. [PMID: 34670022 PMCID: PMC8841449 DOI: 10.1111/cts.13169] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 08/31/2021] [Accepted: 09/05/2021] [Indexed: 11/28/2022] Open
Abstract
There are contrasting findings regarding the effect of HIV on the pharmacokinetics of first‐line anti‐tubercular drugs (FLATDs) due to a lack of prospective controlled clinical studies, including patients with tuberculosis (TB) and patients with TB living with HIV. This study aims to assess the effect of HIV coinfection and antiviral therapy on the plasma exposure to FLATDs in patients with TB. HIV negative (TB‐HIV− group; n = 15) and HIV positive (TB‐HIV+ group; n = 18) adult patients with TB were enrolled during the second month of FLATDs treatment. All TB‐HIV+ patients were on treatment with lamivudine, tenofovir (or zidovudine), and raltegravir (or efavirenz). Serial blood sampling was collected over 24 h and FLATDs pharmacokinetic parameters were evaluated using noncompartmental methods. In the TB‐HIV+ patients, dose‐normalized plasma exposure area under the curve from zero to 24 h (nAUC0–24; geometric mean and 95% confidence interval [CI]) values at steady‐state to rifampicin, pyrazinamide, and ethambutol were 18.38 (95% CI 13.74–24.59), 238.21 (95% CI 191.09–296.95), and 18.33 (95% CI 14.56–23.09) µg∙h/ml, respectively. Similar plasma exposure was found in the TB‐HIV− patients. The geometric mean and 90% CI of the ratios between TB‐HIV− and TB‐HIV+ groups suggest no significant pharmacokinetic interaction between the selected antivirals and FLATDs. Likewise, HIV coinfection itself does not appear to have any effect on the plasma exposure to FLATDs.
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Affiliation(s)
| | - Valdes Roberto Bollela
- Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Adriana Rocha
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Oscar Della Pasqua
- Clinical Pharmacology & Therapeutics Group, School of Pharmacy - University College London, London, UK
| | - Vera Lucia Lanchote
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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15
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Denti P, Wasmann RE, van Rie A, Winckler J, Bekker A, Rabie H, Hesseling AC, van der Laan LE, Gonzalez-Martinez C, Zar HJ, Davies G, Wiesner L, Svensson EM, McIlleron HM. Optimizing dosing and fixed-dose combinations of rifampicin, isoniazid, and pyrazinamide in pediatric patients with tuberculosis: a prospective population pharmacokinetic study. Clin Infect Dis 2021; 75:141-151. [PMID: 34665866 DOI: 10.1093/cid/ciab908] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND In 2010, the WHO revised dosing guidelines for treatment of childhood tuberculosis. Our aim was to investigate first-line antituberculosis drug exposures under these guidelines, explore dose optimization using the current dispersible fixed-dose combination (FDC) table of rifampicin/isoniazid/pyrazinamide; 75/50/150 mg , and suggest a new FDC with revised weight-bands. METHODS Children with drug-susceptible tuberculosis in Malawi and South Africa underwent pharmacokinetic sampling while receiving first-line tuberculosis drugs as single formulations according the 2010 WHO recommended doses. Nonlinear mixed-effects modelling and simulation was used to design the optimal FDC and weight-band dosing strategy for achieving the pharmacokinetic targets based on literature-derived adult AUC0-24h for rifampicin (38.7-72.9) isoniazid (11.6-26.3) and pyrazinamide (233-429 mg∙h/L). RESULTS 180 children (42% female; 13.9% HIV-infected; median [range] age 1.9 [0.22-12] years; weight 10.7 [3.20-28.8] kg) were administered 1, 2, 3, or 4 FDC tablets (rifampicin/isoniazid/pyrazinamide 75/50/150 mg) daily for 4-8, 8-12, 12-16, and 16-25 kg weight-bands, respectively. Rifampicin exposure (for weight and age) was up to 50% lower than in adults. Increasing the tablet number resulted in adequate rifampicin but relatively high isoniazid and pyrazinamide exposures. Administering 1, 2, 3, or 4 optimized FDC tablets (rifampicin/isoniazid/pyrazinamide 120/35/130 mg) to children <6, 6-13, 13-20 and 20-25 kg, and 0.5 tablet in <3-month-olds with immature metabolism, improved exposures to all three drugs. CONCLUSION Current pediatric FDC doses resulted in low rifampicin exposures. Optimal dosing of all drugs cannot be achieved with the current FDCs. We propose a new FDC formulation and revised weight-bands.
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Affiliation(s)
- Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Roeland E Wasmann
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Annelies van Rie
- Family Medicine and Population Health, Faculty of Medicine, University of Antwerp, Antwerp, Belgium
| | - Jana Winckler
- Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Adrie Bekker
- Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Helena Rabie
- Department of Paediatrics and Child Health and FAMily Centre for Research with Ubuntu (FAMCRU) Stellenbosch University and Tygerberg Hospital, Cape Town, South Africa
| | - Anneke C Hesseling
- Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Louvina E van der Laan
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa.,Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Carmen Gonzalez-Martinez
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi/Liverpool School of Tropical Medicine
| | - Heather J Zar
- Department of Paediatrics and Child Health, Red Cross War Memorial Children's Hospital, and SA-MRC Unit on Child & Adolescent Health, University of Cape Town, South Africa
| | - Gerry Davies
- Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom.,Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Lubbe Wiesner
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Elin M Svensson
- Department of Pharmacy, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Pharmacy, Uppsala University, Uppsala, Sweden
| | - Helen M McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa.,Wellcome Centre for Infectious Diseases Research in Africa (CIDRI-Africa), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
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16
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Sturkenboom MGG, Märtson AG, Svensson EM, Sloan DJ, Dooley KE, van den Elsen SHJ, Denti P, Peloquin CA, Aarnoutse RE, Alffenaar JWC. Population Pharmacokinetics and Bayesian Dose Adjustment to Advance TDM of Anti-TB Drugs. Clin Pharmacokinet 2021; 60:685-710. [PMID: 33674941 PMCID: PMC7935699 DOI: 10.1007/s40262-021-00997-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2021] [Indexed: 02/07/2023]
Abstract
Tuberculosis (TB) is still the number one cause of death due to an infectious disease. Pharmacokinetics and pharmacodynamics of anti-TB drugs are key in the optimization of TB treatment and help to prevent slow response to treatment, acquired drug resistance, and adverse drug effects. The aim of this review was to provide an update on the pharmacokinetics and pharmacodynamics of anti-TB drugs and to show how population pharmacokinetics and Bayesian dose adjustment can be used to optimize treatment. We cover aspects on preclinical, clinical, and population pharmacokinetics of different drugs used for drug-susceptible TB and multidrug-resistant TB. Moreover, we include available data to support therapeutic drug monitoring of these drugs and known pharmacokinetic and pharmacodynamic targets that can be used for optimization of therapy. We have identified a wide range of population pharmacokinetic models for first- and second-line drugs used for TB, which included models built on NONMEM, Pmetrics, ADAPT, MWPharm, Monolix, Phoenix, and NPEM2 software. The first population models were built for isoniazid and rifampicin; however, in recent years, more data have emerged for both new anti-TB drugs, but also for defining targets of older anti-TB drugs. Since the introduction of therapeutic drug monitoring for TB over 3 decades ago, further development of therapeutic drug monitoring in TB next steps will again depend on academic and clinical initiatives. We recommend close collaboration between researchers and the World Health Organization to provide important guideline updates regarding therapeutic drug monitoring and pharmacokinetics/pharmacodynamics.
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Affiliation(s)
- Marieke G G Sturkenboom
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Anne-Grete Märtson
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Elin M Svensson
- Department of Pharmacy, Uppsala University, Uppsala, Sweden.,Department of Pharmacy, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Derek J Sloan
- Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.,Liverpool School of Tropical Medicine, Liverpool, UK.,School of Medicine, University of St Andrews, St Andrews, UK
| | - Kelly E Dooley
- Department of Medicine, Center for Tuberculosis Research, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Simone H J van den Elsen
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.,Department of Clinical Pharmacy, Hospital Group Twente, Almelo, Hengelo, the Netherlands
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Charles A Peloquin
- Department of Pharmacotherapy and Translational Research, College of Pharmacy, University of Florida, Gainesville, FL, USA
| | - Rob E Aarnoutse
- Department of Pharmacy, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Jan-Willem C Alffenaar
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands. .,Faculty of Medicine and Health, School of Pharmacy, The University of Sydney, Pharmacy Building (A15), Sydney, NSW, 2006, Australia. .,Westmead Hospital, Westmead, NSW, Australia. .,Marie Bashir Institute of Infectious Diseases and Biosecurity, University of Sydney, Sydney, NSW, Australia.
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17
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Chirehwa MT, Court R, de Kock M, Wiesner L, de Vries N, Harding J, Gumbo T, Maartens G, Warren R, Denti P, McIlleron H. Population Pharmacokinetics of Cycloserine and Pharmacokinetic/Pharmacodynamic Target Attainment in Multidrug-Resistant Tuberculosis Patients Dosed with Terizidone. Antimicrob Agents Chemother 2020; 64:e01381-20. [PMID: 32816738 PMCID: PMC7577169 DOI: 10.1128/aac.01381-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 08/13/2020] [Indexed: 11/20/2022] Open
Abstract
Cycloserine is a WHO group B drug for the treatment of multidrug-resistant tuberculosis (TB). Pharmacokinetic/pharmacodynamic data for cycloserine when dosed as terizidone are sparse. The aim of this analysis was to describe the population pharmacokinetics of cycloserine when administered as terizidone and predict the doses of terizidone attaining cycloserine exposures associated with efficacy. The plasma cycloserine level was measured 2 to 6 weeks after treatment initiation in patients hospitalized for second-line tuberculosis treatment. The pretreatment MICs of cycloserine were determined for the clinical isolates. We enrolled 132 participants with rifampicin-resistant TB; 79 were HIV positive. The median pretreatment MIC was 16 mg/liter. A one-compartment disposition model with two clearance pathways, nonrenal (0.35 liters/h) and renal (0.43 liters/h), described cycloserine pharmacokinetics well. Nonrenal clearance and the volume of distribution were allometrically scaled using fat-free mass. Smoking increased nonrenal clearance by 41%. Simulations showed that with daily doses of terizidone (750 mg and 1,000 mg for patients weighing ≤45 kg and >45 kg, respectively), the probability of maintaining the plasma cycloserine concentration above the MIC for more than 30% of the dosing interval (30% T>MIC) (which is associated with a 1.0-log10-CFU/ml kill in vitro) exceeded 90% at MIC values of ≤16 mg/liter, but the proportion of patients achieving 100% T>MIC (which is associated with the prevention of resistance) was more than 90% only at MICs of ≤8 mg/liter. Based on a target derived in vitro, the WHO-recommended doses of terizidone are effective for cycloserine MICs of ≤8 mg/liter, and higher doses are required to prevent the development of resistance.
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Affiliation(s)
- Maxwell T Chirehwa
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Richard Court
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Mariana de Kock
- NRF-DSI Centre of Excellence in Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Stellenbosch University, Cape Town, South Africa
| | - Lubbe Wiesner
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | | | | | | | - Gary Maartens
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
- Wellcome Centre for Infectious Diseases Research in Africa (CIDRI-Africa), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Rob Warren
- NRF-DSI Centre of Excellence in Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Stellenbosch University, Cape Town, South Africa
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Helen McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
- Wellcome Centre for Infectious Diseases Research in Africa (CIDRI-Africa), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
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18
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Muliaditan M, Della Pasqua O. How long will treatment guidelines for TB continue to overlook variability in drug exposure? J Antimicrob Chemother 2020; 74:3274-3280. [PMID: 31360999 DOI: 10.1093/jac/dkz319] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 06/23/2019] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Despite wide clinical acceptance, the use of weight-banded dosing regimens for the treatment of TB in adults has been defined on an empirical basis. The potential impact of known covariate factors on exposure to different drugs has not been taken into account. OBJECTIVES To evaluate the effect of demographic factors on the exposure to standard of care drugs after weight-banded dosing, as currently recommended by TB treatment guidelines. In addition, we aim to identify alternative dosing regimens that ensure comparable systemic exposure across the overall patient population. METHODS Clinical trial simulations were performed to assess the differences in systemic exposure in a cohort of virtual patients. Secondary pharmacokinetic parameters were used to evaluate the adequacy of each regimen along with the percentage of patients achieving predefined thresholds. RESULTS Our results show that patients weighing less than 40 kg are underexposed relative to patients with higher body weight. The opposite trend was observed following a crude weight band-based dosing regimen with 50 kg as the cut-off point. Simulations indicate that a fixed-dose regimen based on three (<40 kg), four (40-70 kg) or five (>70 kg) tablets of 150 mg rifampicin, 75 mg isoniazid, 400 mg pyrazinamide and 275 mg ethambutol reduces variability in exposure, increasing the overall probability of favourable long-term outcome across the population. CONCLUSIONS These findings suggest the need to revisit current guidelines for the dose of standard of care drugs for TB treatment in adults. The proposed fixed-dose regimen should be considered in future clinical trials.
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Affiliation(s)
- Morris Muliaditan
- Clinical Pharmacology & Therapeutics Group, University College London, London, UK
| | - Oscar Della Pasqua
- Clinical Pharmacology & Therapeutics Group, University College London, London, UK.,Clinical Pharmacology Modelling and Simulation, GlaxoSmithKline, Uxbridge, UK
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19
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A Systematic Review on the Effect of HIV Infection on the Pharmacokinetics of First-Line Tuberculosis Drugs. Clin Pharmacokinet 2020; 58:747-766. [PMID: 30406475 PMCID: PMC7019645 DOI: 10.1007/s40262-018-0716-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Introduction Contrasting findings have been published regarding the effect of human immunodeficiency virus (HIV) on tuberculosis (TB) drug pharmacokinetics (PK). Objectives The aim of this systematic review was to investigate the effect of HIV infection on the PK of the first-line TB drugs (FLDs) rifampicin, isoniazid, pyrazinamide and ethambutol by assessing all published literature. Methods Searches were performed in MEDLINE (through PubMed) and EMBASE to find original studies evaluating the effect of HIV infection on the PK of FLDs. The included studies were assessed for bias and clinical relevance. PK data were extracted to provide insight into the difference of FLD PK between HIV-positive and HIV-negative TB patients. This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and its protocol was registered at PROSPERO (registration number CRD42017067250). Results Overall, 27 studies were eligible for inclusion. The available studies provide a heterogeneous dataset from which consistent results could not be obtained. In both HIV-positive and HIV-negative TB groups, rifampicin (13 of 15) and ethambutol (4 of 8) peak concentration (Cmax) often did not achieve the minimum reference values. More than half of the studies (11 of 20) that included both HIV-positive and HIV-negative TB groups showed statistically significantly altered FLD area under the concentration–time curve and/or Cmax for at least one FLD. Conclusions HIV infection may be one of several factors that reduce FLD exposure. We could not make general recommendations with respect to the role of dosing. There is a need for consistent and homogeneous studies to be conducted.
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Population Pharmacokinetics of Isoniazid, Pyrazinamide, and Ethambutol in Pregnant South African Women with Tuberculosis and HIV. Antimicrob Agents Chemother 2020; 64:AAC.01978-19. [PMID: 31844002 DOI: 10.1128/aac.01978-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 12/05/2019] [Indexed: 11/20/2022] Open
Abstract
Tuberculosis is an important cause of maternal morbidity, but little is known about the effects of pregnancy on antituberculosis drug concentrations. We developed population pharmacokinetic models to describe drug dispositions of isoniazid, pyrazinamide, and ethambutol in pregnant women with tuberculosis and HIV. HIV-positive pregnant women with tuberculosis receiving standard first-line tuberculosis treatment and participating in Tshepiso, a prospective cohort study in Soweto, South Africa, underwent sparse pharmacokinetic sampling at >36 weeks of gestation and 7 weeks postpartum. The effects of pregnancy on the pharmacokinetics of isoniazid, pyrazinamide, and ethambutol were investigated via population pharmacokinetic modeling. Isoniazid, pyrazinamide, and ethambutol concentrations were available for 29, 18, and 18 women, respectively. Their median weight was 66 kg while pregnant and 64 kg postpartum. No significant differences were observed in drug clearance, volume of distribution, or bioavailability during and after pregnancy. The model-estimated isoniazid, pyrazinamide, and ethambutol area under the concentration-time curve from 0 to 24 h (AUC0-24) medians were, respectively, 6.88, 419, and 16.5 mg · h/liter during pregnancy versus 5.01, 407, and 19.0 mg · h/liter postpartum. The model-estimated maximum concentration (C max) medians for isoniazid, pyrazinamide, and ethambutol were, respectively, 1.39, 35.9, and 1.82 mg/liter during pregnancy versus 1.43, 34.5, and 2.11 mg/liter postpartum. A posteriori power calculations determined that our analysis was powered 91.8%, 59.2%, and 90.1% at a P of <0.01 to detect a 40% decrease in the AUCs of isoniazid, pyrazinamide, and ethambutol, respectively. Pregnancy does not appear to cause relevant changes in the exposure to isoniazid, pyrazinamide, and ethambutol. Additional studies of antituberculosis drugs in pregnancy are needed.
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21
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Lamont EA, Baughn AD. Impact of the host environment on the antitubercular action of pyrazinamide. EBioMedicine 2019; 49:374-380. [PMID: 31669220 PMCID: PMC6945238 DOI: 10.1016/j.ebiom.2019.10.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 10/01/2019] [Accepted: 10/01/2019] [Indexed: 01/05/2023] Open
Abstract
Pyrazinamide remains the only drug in the tuberculosis pharmacopeia to drastically shorten first-line therapy from nine to six months. Due to its unparalleled ability to sterilize non-replicating bacilli and reduce relapse rates, PZA is expected to be irreplaceable in future therapies against tuberculosis. While the molecular target of PZA is unclear, recent pharmacokinetic studies using small animal models and patient samples have highlighted the importance of host metabolism and immune responses in PZA efficacy. Delineating which host factors are important for PZA action will be integral to the design of next-generation therapies to shorten current TB drug regimens as well as to overcome treatment limitations in some patients. In this review, we discuss evidence for influence of the host environment on PZA activity, targets for PZA mechanism of action, recent studies in PZA pharmacokinetics, PZA antagonism and synergy with other first-line anti-TB drugs, and implications for future research.
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Affiliation(s)
- Elise A Lamont
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Anthony D Baughn
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN, 55455, USA.
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22
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Court R, Chirehwa MT, Wiesner L, Wright B, Smythe W, Kramer N, McIlleron H. Quality assurance of rifampicin-containing fixed-drug combinations in South Africa: dosing implications. Int J Tuberc Lung Dis 2019; 22:537-543. [PMID: 29663959 PMCID: PMC5905389 DOI: 10.5588/ijtld.17.0697] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING: Rifampicin (RMP) drives treatment response in drug-susceptible tuberculosis. Low RMP concentrations increase the risk of poor outcomes, and drug quality needs to be excluded as a contributor to low RMP exposure. OBJECTIVES AND DESIGN: We performed an open-label, three-way cross-over study of three licensed RMP-containing formulations widely used in South Africa to evaluate the bioavailability of RMP in a two-drug fixed-dose combination tablet (2FDC) and a four-drug FDC (4FDC) against a single-drug reference. RMP dosed at 600 mg was administered 2 weeks apart in random sequence. Plasma RMP concentrations were measured pre-dose and 1, 2, 3, 4, 6, 8 and 12 h post-dose. The area under the concentration-time curve (AUC0–12) of the FDCs was compared to the single drug reference. Simulations were used to predict the impact of our findings. RESULTS: Twenty healthy volunteers (median age 22.8 years, body mass index 24.2 kg/m2) completed the study. The AUC0–12 of the 4FDC/reference (geometric mean ratio [GMR] 78%, 90%CI 69–89) indicated an average 20% reduction in RMP bioavailability in the 4FDC. The 2FDC/reference (GMR 104%, 90%CI 97–111) was bioequivalent. Simulations suggested dose adjustments to compensate for the poor bioavailability of RMP with the 4FDC, and revised weight-band doses to prevent systematic underdosing of low-weight patients. CONCLUSION: Post-marketing surveillance of in vivo bioavailability of RMP and improved weight band-based dosing are recommended.
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Affiliation(s)
- R Court
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - M T Chirehwa
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - L Wiesner
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - B Wright
- Clinical Research Centre, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa, South Africa
| | - W Smythe
- Clinical Research Centre, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa, South Africa
| | - N Kramer
- Clinical Research Centre, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa, South Africa
| | - H McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
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Low Antituberculosis Drug Concentrations in HIV-Tuberculosis-Coinfected Adults with Low Body Weight: Is It Time To Update Dosing Guidelines? Antimicrob Agents Chemother 2019; 63:AAC.02174-18. [PMID: 30910890 DOI: 10.1128/aac.02174-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Accepted: 03/12/2019] [Indexed: 01/28/2023] Open
Abstract
Antituberculosis drugs display large pharmacokinetic variability, which may be influenced by several factors, including body size, genetic differences, and drug-drug interactions. We set out to determine these factors, quantify their effect, and determine the dose adjustments necessary for optimal drug concentrations. HIV-infected Ugandan adults with pulmonary tuberculosis treated according to international weight-based dosing guidelines underwent pharmacokinetic sampling (1, 2, and 4 h after drug intake) 2, 8, and 24 weeks after treatment initiation. Between May 2013 and November 2015, we enrolled 268 patients (148 males) with a median weight of 53.5 (interquartile range [IQR], 47.5 to 59.0) kg and a median age of 35 (IQR, 29 to 40) years. Population pharmacokinetic modeling was used to interpret the data and revealed that patients weighing <55 kg achieved lower concentrations than those in higher weight bands for all drugs in the regimen. The models predicted that this imbalance could be solved with a dose increment of one fixed-dose combination (FDC) tablet for the weight bands of 30 to 37 and 38 to 54 kg. Additionally, the concomitant use of efavirenz increased isoniazid clearance by 24.1%, while bioavailability and absorption of rifampin and isoniazid varied up to 30% in patients on different formulations. Current dosing guidelines lead to lower drug exposure in patients in the lower weight bands. Simply adding one FDC tablet to current weight band-based dosing would address these differences in exposure and possibly improve outcomes. Lower isoniazid exposures due to efavirenz deserve further attention, as does the quality of currently used drug formulations of anti-TB drugs. (This study has been registered at ClinicalTrials.gov under identifier NCT01782950.).
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Chirehwa MT, McIlleron H, Wiesner L, Affolabi D, Bah-Sow O, Merle C, Denti P. Effect of efavirenz-based antiretroviral therapy and high-dose rifampicin on the pharmacokinetics of isoniazid and acetyl-isoniazid. J Antimicrob Chemother 2019; 74:139-148. [PMID: 30239829 PMCID: PMC6293084 DOI: 10.1093/jac/dky378] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 08/17/2018] [Accepted: 08/24/2018] [Indexed: 02/03/2023] Open
Abstract
Objectives To describe the pharmacokinetics of isoniazid and acetyl-isoniazid in TB/HIV-coinfected patients, and assess the effects of efavirenz co-administration and a 50% increase in the dose of rifampicin on the pharmacokinetic parameters of isoniazid and acetyl-isoniazid. Methods TB/HIV-coinfected patients participating in the three-treatment-arm RAFA randomized controlled trial conducted in West Africa were recruited into the pharmacokinetics sub-study. Five serial blood samples were collected on a single visit between 4 and 8 weeks after initiation of antituberculosis treatment. Concentration-time data for isoniazid and acetyl-isoniazid were analysed using non-linear mixed-effects models. Results Isoniazid concentrations from 150 patients were available for analysis, and 79 of these (53%) also had concentrations of acetyl-isoniazid. Isoniazid pharmacokinetics was best described with a two-compartment disposition model with lagged first-order absorption and elimination using a semi-mechanistic model describing hepatic extraction. The model identified two elimination pathways, separating formation of acetyl-isoniazid from other routes of metabolism. The predicted AUC0-24 is reduced by 29% in patients who are fast acetylators of isoniazid and receiving efavirenz-based ART (6.73 versus 4.68 mg·h/L). In slow acetylators, efavirenz-based ART had no effect on isoniazid exposure (AUC0-24 = 17.5 mg·h/L). Conclusions Efavirenz-based ART affects the acetylation metabolic pathway amongst rapid acetylators, resulting in reduced exposure to isoniazid. Pharmacokinetics of isoniazid and acetyl-isoniazid were not influenced by the 50% increase in rifampicin dose.
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Affiliation(s)
- Maxwell T Chirehwa
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Helen McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Lubbe Wiesner
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Dissou Affolabi
- National Programme for Tuberculosis and Pulmonary Diseases, Cotonou, Benin
| | - Oumou Bah-Sow
- Service de Pneumo-Phtisiologie, Hopital Ignace Deen, Conakry, Guinea
| | - Corinne Merle
- London School of Hygiene & Tropical Medicine, London, UK
- UNICEF/UNDP/World Bank/WHO Special Programme on Research and Training in Tropical Diseases (TDR), Geneva, Switzerland
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
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McIlleron H, Chirehwa MT. Current research toward optimizing dosing of first-line antituberculosis treatment. Expert Rev Anti Infect Ther 2018; 17:27-38. [PMID: 30501530 PMCID: PMC6364307 DOI: 10.1080/14787210.2019.1555031] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Introduction: Drug concentrations in tuberculosis patients on standard regimens vary widely with clinically important consequences. Areas covered: We review the available literature identifying factors correlated with pharmacokinetic variability of antituberculosis drugs. Based on population pharmacokinetic models and the weight, height, and sex distributions in a large data base of African tuberculosis patients, we propose simplified weight-based doses of the available fixed dose combination(FDC) for adults with drug susceptible tuberculosis. Emerging studies will support optimized weight-based dosing for children. Other sources of important pharmacokinetic variability include genetic variants, drug-drug interactions, formulation quality, and methods of preparation and administration. Expert commentary: Optimized weight band-based dosing will result in more equitable distribution of drug exposures by weight. The use of high doses of isoniazid in patients with drug-resistant tuberculosis would be safer and more effective if a feasible test was developed to allow stratified dosing according to acetylator type. There is an urgent need for more suitable formulations of many second-line drugs for children. The adoption of new technologies and efficient FDC design may allow further advances for patients and treatment programs. Lastly, current efforts to ensure adequate quality of antituberculosis drug products are not preventing the use of substandard products to treat patients with tuberculosis.
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Affiliation(s)
- Helen McIlleron
- a Division of Clinical Pharmacology, Department of Medicine , University of Cape Town , Cape Town , South Africa
| | - Maxwell T Chirehwa
- a Division of Clinical Pharmacology, Department of Medicine , University of Cape Town , Cape Town , South Africa
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26
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Alfarisi O, Alghamdi WA, Al-Shaer MH, Dooley KE, Peloquin CA. Rifampin vs. rifapentine: what is the preferred rifamycin for tuberculosis? Expert Rev Clin Pharmacol 2017; 10:1027-1036. [PMID: 28803492 DOI: 10.1080/17512433.2017.1366311] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
INTRODUCTION One-third of the world's population is infected with Mycobacterium tuberculosis (M.tb.). Latent tuberculosis infection (LTBI) can progress to tuberculosis disease, the leading cause of death by infection. Rifamycin antibiotics, like rifampin and rifapentine, have unique sterilizing activity against M.tb. What are the advantages of each for LTBI or tuberculosis treatment? Areas covered: We review studies assessing the pharmacokinetics (PK), pharmacodynamics (PD), drug interaction risk, safety, and efficacy of rifampin and rifapentine and provide basis for comparing them. Expert commentary: Rifampin has shorter half-life, higher MIC against M.tb, lower protein binding, and better distribution into cavitary contents than rifapentine. Drug interactions for the two drugs maybe similar in magnitude. For LTBI, rifapentine is effective as convenient, once-weekly, 12-week course of treatment. Rifampin is also effective for LTBI, but must be given daily for four months, therefore, drug interactions are more problematic. For drug-sensitive tuberculosis disease, rifampin remains the standard of care. Safety profile of rifampin is better-described; adverse events differ somewhat for the two drugs. The registered once-weekly rifapentine regimen is inadequate, but higher doses of either drugs may shorten the treatment duration required for effective management of TB. Results of clinical trials evaluating high-dose rifamycin regimens are eagerly awaited.
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Affiliation(s)
- Omamah Alfarisi
- a Department of Medicine , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Wael A Alghamdi
- b Department of Pharmacotherapy and Translational Research , University of Florida, College of Pharmacy , Gainesville , FL , USA.,c Infectious Disease Pharmacokinetics Laboratory , University of Florida , Gainesville , FL , USA
| | - Mohammad H Al-Shaer
- b Department of Pharmacotherapy and Translational Research , University of Florida, College of Pharmacy , Gainesville , FL , USA.,c Infectious Disease Pharmacokinetics Laboratory , University of Florida , Gainesville , FL , USA
| | - Kelly E Dooley
- a Department of Medicine , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Charles A Peloquin
- b Department of Pharmacotherapy and Translational Research , University of Florida, College of Pharmacy , Gainesville , FL , USA.,c Infectious Disease Pharmacokinetics Laboratory , University of Florida , Gainesville , FL , USA
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Pharmacokinetics of Pyrazinamide and Optimal Dosing Regimens for Drug-Sensitive and -Resistant Tuberculosis. Antimicrob Agents Chemother 2017; 61:AAC.00490-17. [PMID: 28607022 DOI: 10.1128/aac.00490-17] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 05/24/2017] [Indexed: 11/20/2022] Open
Abstract
Pyrazinamide is used in the treatment of tuberculosis (TB) because its sterilizing effect against tubercle bacilli allows the shortening of treatment. It is part of standard treatment for drug-susceptible and drug-resistant TB, and it is being considered as a companion drug in novel regimens. The aim of this analysis was to characterize factors contributing to the variability in exposure and to evaluate drug exposures using alternative doses, thus providing evidence to support revised dosing recommendations for drug-susceptible and multidrug-resistant tuberculosis (MDR-TB). Pyrazinamide pharmacokinetic (PK) data from 61 HIV/TB-coinfected patients in South Africa were used in the analysis. The patients were administered weight-adjusted doses of pyrazinamide, rifampin, isoniazid, and ethambutol in fixed-dose combination tablets according to WHO guidelines and underwent intensive PK sampling on days 1, 8, 15, and 29. The data were interpreted using nonlinear mixed-effects modeling. PK profiles were best described using a one-compartment model with first-order elimination. Allometric scaling was applied to disposition parameters using fat-free mass. Clearance increased by 14% from the 1st day to the 29th day of treatment. More than 50% of patients with weight less than 55 kg achieved lower pyrazinamide exposures at steady state than the targeted area under the concentration-time curve from 0 to 24 h of 363 mg · h/liter. Among patients with drug-susceptible TB, adding 400 mg to the dose for those weighing 30 to 54 kg improved exposure. Average pyrazinamide exposure in different weight bands among patients with MDR-TB could be matched by administering 1,500 mg, 1,750 mg, and 2,000 mg to patients in the 33- to 50-kg, 51- to 70-kg, and greater than 70-kg weight bands, respectively.
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Rockwood N, Pasipanodya JG, Denti P, Sirgel F, Lesosky M, Gumbo T, Meintjes G, McIlleron H, Wilkinson RJ. Concentration-Dependent Antagonism and Culture Conversion in Pulmonary Tuberculosis. Clin Infect Dis 2017; 64:1350-1359. [PMID: 28205671 PMCID: PMC5411399 DOI: 10.1093/cid/cix158] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2016] [Accepted: 02/15/2017] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND There is scant evidence to support target drug exposures for optimal tuberculosis outcomes. We therefore assessed whether pharmacokinetic/pharmacodynamic (PK/PD) parameters could predict 2-month culture conversion. METHODS One hundred patients with pulmonary tuberculosis (65% human immunodeficiency virus coinfected) were intensively sampled to determine rifampicin, isoniazid, and pyrazinamide plasma concentrations after 7-8 weeks of therapy, and PK parameters determined using nonlinear mixed-effects models. Detailed clinical data and sputum for culture were collected at baseline, 2 months, and 5-6 months. Minimum inhibitory concentrations (MICs) were determined on baseline isolates. Multivariate logistic regression and the assumption-free multivariate adaptive regression splines (MARS) were used to identify clinical and PK/PD predictors of 2-month culture conversion. Potential PK/PD predictors included 0- to 24-hour area under the curve (AUC0-24), maximum concentration (Cmax), AUC0-24/MIC, Cmax/MIC, and percentage of time that concentrations persisted above the MIC (%TMIC). RESULTS Twenty-six percent of patients had Cmax of rifampicin <8 mg/L, pyrazinamide <35 mg/L, and isoniazid <3 mg/L. No relationship was found between PK exposures and 2-month culture conversion using multivariate logistic regression after adjusting for MIC. However, MARS identified negative interactions between isoniazid Cmax and rifampicin Cmax/MIC ratio on 2-month culture conversion. If isoniazid Cmax was <4.6 mg/L and rifampicin Cmax/MIC <28, the isoniazid concentration had an antagonistic effect on culture conversion. For patients with isoniazid Cmax >4.6 mg/L, higher isoniazid exposures were associated with improved rates of culture conversion. CONCLUSIONS PK/PD analyses using MARS identified isoniazid Cmax and rifampicin Cmax/MIC thresholds below which there is concentration-dependent antagonism that reduces 2-month sputum culture conversion.
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Affiliation(s)
- Neesha Rockwood
- Department of Medicine, Imperial College London, United Kingdom
- Wellcome Center for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town
| | - Frederick Sirgel
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical Tuberculosis Research/ South African Medical Research Foundation Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Health Sciences, Stellenbosch University, Tygerberg
| | - Maia Lesosky
- Wellcome Center for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
- Division of Epidemiology and Biostatistics, School of Public Health and Family Medicine, and
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
- Department of Medicine, University of Cape Town, South Africa; and
| | - Graeme Meintjes
- Department of Medicine, Imperial College London, United Kingdom
- Department of Medicine, University of Cape Town, South Africa; and
| | - Helen McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town
| | - Robert J Wilkinson
- Department of Medicine, Imperial College London, United Kingdom
- Wellcome Center 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; and
- Francis Crick Institute, London, United Kingdom
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