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Moore KT, Zannikos PN, Masters JC, Willmann S, Shen J, Frost C. The Importance of Assessing Drug Pharmacokinetics and Pharmacodynamics in the Obese Population During Drug Development. J Clin Pharmacol 2023; 63 Suppl 2:S78-S84. [PMID: 37942912 DOI: 10.1002/jcph.2361] [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: 07/14/2023] [Accepted: 09/21/2023] [Indexed: 11/10/2023]
Abstract
Obesity remains a US national health crisis and a growing concern worldwide. Concerningly, individuals who are obese are at an increased risk for comorbid diseases that include, but are not limited to, hypertension, diabetes, cardiovascular disease, and cancer. Beyond the risk for developing these conditions, obesity may also impact the pharmacological activity of the therapies being used to treat them and other disease states. The pharmacokinetics (PK), pharmacodynamics (PD), safety, and efficacy of therapies, both currently marketed and under clinical development, may be directly impacted by the physiological alterations that occur secondary to the occurrence of chronic excess body weight. The increased prevalence of this disease should not be ignored. Both private and federal institutions involved in drug research and development should consider, as appropriate, a greater inclusion of individuals who are obese in clinical trials throughout the entirety of drug development, and leverage the available PK, PD, safety, and efficacy data to make more informed dosing recommendations.
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Affiliation(s)
- Kenneth T Moore
- Johnson & Johnson Innovative Medicine, Scientific Affairs, Titusville, NJ, USA
| | - Peter N Zannikos
- Johnson & Johnson Innovative Medicine, Clinical Pharmacology and Pharmacometrics, Titusville, NJ, USA
| | - Joanna C Masters
- Pfizer Worldwide Research, Development and Medical, Clinical Pharmacology and Bioanalytics, San Diego, CA, USA
| | - Stefan Willmann
- Bayer AG, Pharmaceuticals, Research & Development, Pharmacometrics/Modeling & Simulation, Wuppertal, Germany
| | - Jinshan Shen
- Relay Therapeutics, Clinical Pharmacology, Cambridge, MA, USA
| | - Charles Frost
- Bristol-Myers Squibb, Global Scientific and Regulatory Documentation, Princeton, NJ, USA
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2
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Research Progress of Population Pharmacokinetic of Metformin. BIOMED RESEARCH INTERNATIONAL 2022; 2022:4071111. [PMID: 36578804 PMCID: PMC9792241 DOI: 10.1155/2022/4071111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/21/2022] [Accepted: 12/03/2022] [Indexed: 12/23/2022]
Abstract
Metformin is commonly used as first-line treatment for T2DM (type2 diabetes mellitus). Owing to the high pharmacokinetic (PK) variability, several population pharmacokinetic (PPK) models have been developed for metformin to explore potential covariates that affect its pharmacokinetic variation. This comprehensive review summarized the published PPK studies of metformin, aimed to summarize PPK models of metformin. Most studies described metformin pharmacokinetics as a 2-compartment (2-CMT) model with 4 study describing its pharmacokinetics as 1-compartment (1-CMT). Studies on metformin PPK have shown that obesity, creatinine clearance (CLCr), gene polymorphism, degree of renal function damage, and pathological conditions all have a certain impact on the PK parameters of metformin. It is particularly important to formulate individualized dosing regimens. For future PPK studies of metformin, we believe that more attention should be paid to special populations.
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Syafhan NF, Donnelly R, Harper R, Harding J, Mulligan C, Hogg A, Scott M, Fleming G, Scullin C, Hawwa AF, Chen G, Parsons C, McElnay JC. Adherence to metformin in adults with type 2 diabetes: a combined method approach. J Pharm Policy Pract 2022; 15:61. [PMID: 36224634 PMCID: PMC9554867 DOI: 10.1186/s40545-022-00457-5] [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] [Received: 06/28/2022] [Accepted: 10/02/2022] [Indexed: 11/17/2022] Open
Abstract
Background Medication adherence, one of the most important aspects in the process of optimal medicines use, is unfortunately still a major challenge in modern healthcare, and further research is required into how adherence can be assessed and optimised. The aim of this study was to use a combined method approach of self-report and dried blood spot (DBS) sampling coupled with population pharmacokinetic (PopPK) modelling, to assess adherence to metformin in adult patients with type 2 diabetes. Further aims were to assess metformin exposure levels in patients, determine factors associated with non-adherence with prescribed metformin, and to explore the relationship between adherence and therapeutic outcomes. Methods A combined method approach was used to evaluate metformin adherence in patients with type 2 diabetes who had been prescribed metformin for a minimum period of 6 months. Patients were recruited from consultant-led diabetic outpatient clinics at three hospitals in Northern Ireland, UK. Data collection involved self-reported questionnaires [Medication Adherence Report Scale (MARS), Beliefs about Medicines Questionnaire and Centre for Epidemiologic Studies Depression Scale], direct measurement of metformin concentration in DBS samples, and researcher-led patient interviews. The DBS sampling approach was coupled with population pharmacokinetic (PopPK) modelling, which took account of patient characteristics, metformin dosage and type of formulation prescribed (immediate or sustained release). Results The proportion of patients considered to be adherent to their prescribed metformin, derived from self-reported MARS scores and metformin concentration in DBS samples, was 61.2% (74 out of 121 patients). The majority (n = 103, 85.1%) of recruited patients had metformin exposure levels that fell within the therapeutic range. However, 17 patients (14.1%) had low exposure to metformin and one patient (0.8%) had undetectable metformin level in their blood sample (non-exposure). Metformin self-administration and use of a purchased adherence pill box significantly increased the probability of a patient being classified as adherent based on logistic regression analysis. Both HbA1c and random glucose levels (representing poor glycaemic control) in the present research were, however, not statistically linked to non-adherence to metformin (P > 0.05). Conclusions A significant proportion of participating patients were not fully adherent with their therapy. DBS sampling together with the use of a published PopPK model was a useful, novel, direct, objective approach to estimate levels of adherence in adult patients with type 2 diabetes (61.2%). Supplementary Information The online version contains supplementary material available at 10.1186/s40545-022-00457-5.
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Affiliation(s)
- Nadia Farhanah Syafhan
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Belfast, UK.,Department of Clinical Pharmacy, Faculty of Pharmacy, Universitas Indonesia, Depok, Indonesia
| | - Rosemary Donnelly
- Ulster Hospital, South Eastern Health and Social Care Trust, Belfast, UK
| | - Roy Harper
- Ulster Hospital, South Eastern Health and Social Care Trust, Belfast, UK
| | - Janet Harding
- Ulster Hospital, South Eastern Health and Social Care Trust, Belfast, UK
| | - Ciara Mulligan
- Ulster Hospital, South Eastern Health and Social Care Trust, Belfast, UK
| | - Anita Hogg
- Medicines Optimisation Innovation Centre, Northern Health Social Care Trust, Antrim, Northern Ireland, UK
| | - Michael Scott
- Medicines Optimisation Innovation Centre, Northern Health Social Care Trust, Antrim, Northern Ireland, UK
| | - Glenda Fleming
- Medicines Optimisation Innovation Centre, Northern Health Social Care Trust, Antrim, Northern Ireland, UK
| | - Claire Scullin
- Medicines Optimisation Innovation Centre, Northern Health Social Care Trust, Antrim, Northern Ireland, UK
| | - Ahmed F Hawwa
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Belfast, UK.,School of Biological Sciences. Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Gaoyun Chen
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Carole Parsons
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - James C McElnay
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Belfast, UK.
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4
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Zhang T, Krekels EHJ, Smit C, Knibbe CAJ. Drug pharmacokinetics in the obese population: challenging common assumptions on predictors of obesity-related parameter changes. Expert Opin Drug Metab Toxicol 2022; 18:657-674. [PMID: 36217846 DOI: 10.1080/17425255.2022.2132931] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Obesity is associated with many physiological changes. We review available evidence regarding five commonly accepted assumptions to a priori predict the impact of obesity on drug pharmacokinetics (PK). AREAS COVERED The investigated assumptions are: 1) lean body weight is the preferred descriptor of clearance and dose adjustments; 2) volume of distribution increases for lipophilic, but not for hydrophilic drugs; 3) CYP-3A4 activity is suppressed and UGT activity is increased, implying decreased and increased dose requirements for substrates of these enzyme systems, respectively; 4) glomerular filtration rate is enhanced, necessitating higher doses for drugs cleared through glomerular filtration; 5) drug dosing information from obese adults can be extrapolated to obese adolescents. EXPERT OPINION Available literature contradicts, or at least limits the generalizability, of all five assumptions. Clinical studies should focus on quantifying the impact of duration and severity of obesity on drug PK in adults and adolescents, and also include oral bioavailability and pharmacodynamics in these studies. Physiologically-based PK approaches can be used to predict PK changes for individual drugs, but can also be used to define in general terms based on patient characteristics and drug properties, when certain assumptions can or cannot be expected to be systematically accurate.
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Affiliation(s)
- Tan Zhang
- Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Elke H J Krekels
- Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Cornelis Smit
- Department of Clinical Pharmacy, Antonius Hospital Sneek, The Netherlands
| | - Catherijne A J Knibbe
- Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands.,Department of Clinical Pharmacy, St. Antonius Hospital Nieuwegein, The Netherlands
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Mohammadi Jouabadi S, Nekouei Shahraki M, Peymani P, Stricker BH, Ahmadizar F. Utilization of Pharmacokinetic/Pharmacodynamic Modeling in Pharmacoepidemiological Studies: A Systematic Review on Antiarrhythmic and Glucose-Lowering Medicines. Front Pharmacol 2022; 13:908538. [PMID: 35795566 PMCID: PMC9251370 DOI: 10.3389/fphar.2022.908538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 05/04/2022] [Indexed: 11/22/2022] Open
Abstract
Introduction: In human pharmacology, there are two important scientific branches: clinical pharmacology and pharmacoepidemiology. Pharmacokinetic/pharmacodynamic (PK/PD) modeling is important in preclinical studies and randomized control trials. However, it is rarely used in pharmacoepidemiological studies on the effectiveness and medication safety where the target population is heterogeneous and followed for longer periods. The objective of this literature review was to investigate how far PK/PD modeling is utilized in observational studies on glucose-lowering and antiarrhythmic drugs. Method: A systematic literature search of MEDLINE, Embase, and Web of Science was conducted from January 2010 to 21 February 2020. To calculate the utilization of PK/PD modeling in observational studies, we followed two search strategies. In the first strategy, we screened a 1% random set from 95,672 studies on glucose-lowering and antiarrhythmic drugs on inclusion criteria. In the second strategy, we evaluated the percentage of studies in which PK/PD modeling techniques were utilized. Subsequently, we divided the total number of included studies in the second search strategy by the total number of eligible studies in the first search strategy. Results: The comprehensive search of databases and the manual search of included references yielded a total of 29 studies included in the qualitative synthesis of our systematic review. Nearly all 29 studies had utilized a PK model, whereas only two studies developed a PD model to evaluate the effectiveness of medications. In total, 16 out of 29 studies (55.1%) used a PK/PD model in the observational setting to study effect modification. The utilization of PK/PD modeling in observational studies was calculated as 0.42%. Conclusion: PK/PD modeling techniques were substantially underutilized in observational studies of antiarrhythmic and glucose-lowering drugs during the past decade.
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Affiliation(s)
- Soroush Mohammadi Jouabadi
- Department of Epidemiology, Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, Netherlands
- Division of Pharmacology, Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Mitra Nekouei Shahraki
- Department of Epidemiology, Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Payam Peymani
- Department of Epidemiology, Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Bruno H. Stricker
- Department of Epidemiology, Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, Netherlands
- *Correspondence: Bruno H. Stricker,
| | - Fariba Ahmadizar
- Department of Epidemiology, Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, Netherlands
- Julius Global Health, University Medical Center Utrecht, Utrecht, Netherlands
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6
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Sutkowska E, Fortuna P, Wisniewski J, Sutkowska K, Hodurek P, Gamian A, Kaluza B. Low metformin dose and its therapeutic serum concentration in prediabetes. Sci Rep 2021; 11:11684. [PMID: 34083618 PMCID: PMC8175603 DOI: 10.1038/s41598-021-91174-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 05/10/2021] [Indexed: 11/17/2022] Open
Abstract
This prospective study aimed to analyze whether the patients with pre-diabetes (pre-DM) reach the TC (therapeutic concentration) of the metformin during repeated, low, constant drug dose. The guidelines do not recommend any metformin dose for this group of patients. Based on the previous study after a dose of 1700 mg/day the patients seem to reach the therapeutic drug concentration, which guarantees the glycemic effect. Twenty patients with new-diagnosed pre-DM were treated with a 1500 mg/day regimen of the metformin for 15 weeks. The serum concentration of the drug was assessed by liquid chromatography-mass spectrometry technique at 6 and 15 week of the treatment. The correlation of the serum metformin concentration with BMI (body mass index) and patients' weight was also performed. The mean metformin concentration was: 4.65 μmol/L (± 2.41) and 5.41 μmol/L (± 3.44) (p = 0.27) after 6 and 15 weeks of the treatment respectively. There was a positive correlation between the serum concentration of the metformin and body weight (but not BMI) in the 15th week of the therapy (p = 0.04)- the higher body weight the higher concentration of the metformin. Patients with pre-diabetes can be successfully treated with a low dose of metformin, to reach the drug's therapeutic concentration. Body weight can impact the metformin serum concentration during long-term treatment what should be taken into consideration when choosing the dose because of its pleiotropic effect e.g. on the cardiovascular system via reduction of the oxidative stress and would be not connected with the drug's hypoglycemic effect.ClinicalTrials.gov number: NCT03398356; date of first registration: 01/07/2018.
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Affiliation(s)
- Edyta Sutkowska
- Department and Division of Medical Rehabilitation, Wroclaw Medical University, Borowska 213, 50-556, Wrocław, Poland.
| | - Paulina Fortuna
- Department of Medical Biochemistry, Wroclaw Medical University, Wrocław, Poland
| | - Jerzy Wisniewski
- Department of Medical Biochemistry, Wroclaw Medical University, Wrocław, Poland
| | | | - Pawel Hodurek
- Department of Medical Biochemistry, Wroclaw Medical University, Wrocław, Poland
| | - Andrzej Gamian
- Department of Medical Biochemistry, Wroclaw Medical University, Wrocław, Poland
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland
| | - Bernadetta Kaluza
- Department of Internal Medicine, Endocrinology and Diabetology, Central Clinical Hospital of the Ministry of the Interior, Warsaw, Poland
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Pradhan S, Duffull SB, Wilson LC, Kuan IHS, Walker RJ, Putt TL, Schollum JBW, Wright DFB. Does the intact nephron hypothesis provide a reasonable model for metformin dosing in chronic kidney disease? Br J Clin Pharmacol 2021; 87:4868-4876. [PMID: 34004027 DOI: 10.1111/bcp.14919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 04/20/2021] [Accepted: 05/09/2021] [Indexed: 11/27/2022] Open
Abstract
This research explored the intact nephron hypothesis (INH) as a model for metformin dosing in patients with chronic kidney disease (CKD). The INH assumes that glomerular filtration rate (GFR) will account for all kidney drug handling even for drugs eliminated by tubular secretion like metformin. We conducted two studies: (1) a regression analysis to explore the relationship between metformin clearance and eGFR metrics, and (2) a joint population pharmacokinetic analysis to test the relationship between metformin renal clearance and gentamicin clearance. The relationship between metformin renal clearance and eGFR metrics and gentamicin clearance was found to be linear, suggesting that a proportional dose reduction based on GFR in patients with CKD is reasonable.
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Affiliation(s)
- Sudeep Pradhan
- School of Pharmacy, University of Otago, Dunedin, New Zealand
| | | | - Luke C Wilson
- Department of Medicine, University of Otago, Dunedin, New Zealand
| | | | - Robert J Walker
- Department of Medicine, University of Otago, Dunedin, New Zealand
| | - Tracey L Putt
- Department of Medicine, University of Otago, Dunedin, New Zealand
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Harati R, Vandamme M, Blanchet B, Bardin C, Praz F, Hamoudi RA, Desbois-Mouthon C. Drug-Drug Interaction between Metformin and Sorafenib Alters Antitumor Effect in Hepatocellular Carcinoma Cells. Mol Pharmacol 2021; 100:32-45. [PMID: 33990407 DOI: 10.1124/molpharm.120.000223] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 04/09/2021] [Indexed: 01/21/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and is one of the leading causes of cancer-related deaths worldwide. The multitarget inhibitor sorafenib is a first-line treatment of patients with advanced unresectable HCC. Recent clinical studies have evidenced that patients treated with sorafenib together with the antidiabetic drug metformin have a survival disadvantage compared with patients receiving sorafenib only. Here, we examined whether a clinically relevant dose of metformin (50 mg/kg per day) could influence the antitumoral effects of sorafenib (15 mg/kg per day) in a subcutaneous xenograft model of human HCC growth using two different sequences of administration, i.e., concomitant versus sequential dosing regimens. We observed that the administration of metformin 6 hours prior to sorafenib was significantly less effective in inhibiting tumor growth (15.4% tumor growth inhibition) than concomitant administration of the two drugs (59.5% tumor growth inhibition). In vitro experiments confirmed that pretreatment of different human HCC cell lines with metformin reduced the effects of sorafenib on cell viability, proliferation, and signaling. Transcriptomic analysis confirmed significant differences between xenografted tumors obtained under the concomitant and the sequential dosing regimens. Taken together, these observations call into question the benefit of parallel use of metformin and sorafenib in patients with advanced HCC and diabetes, as the interaction between the two drugs could ultimately compromise patient survival. SIGNIFICANCE STATEMENT: When drugs are administered sequentially, metformin alters the antitumor effect of sorafenib, the reference treatment for advanced hepatocellular carcinoma, in a preclinical murine xenograft model of liver cancer progression as well as in hepatic cancer cell lines. Defective activation of the AMP-activated protein kinase pathway as well as major transcriptomic changes are associated with the loss of the antitumor effect. These results echo recent clinical work reporting a poorer prognosis for patients with liver cancer who were cotreated with metformin and sorafenib.
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Affiliation(s)
- Rania Harati
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Marc Vandamme
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Benoit Blanchet
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Christophe Bardin
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Françoise Praz
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Rifat Akram Hamoudi
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Christèle Desbois-Mouthon
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
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9
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Chen M, You G, Xie C, Yang R, Hu W, Zheng Z, Liu S, Ye L. Pharmacokinetics of metformin in collagen-induced arthritis rats. Biochem Pharmacol 2021; 185:114413. [PMID: 33434538 DOI: 10.1016/j.bcp.2021.114413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 01/05/2021] [Accepted: 01/06/2021] [Indexed: 12/22/2022]
Abstract
Due to the elevated presence of cytokines, the expressions of metabolic enzymes and drug transporters are altered in rheumatoid arthritis (RA). Given the high incidence of diabetes in patients with RA, the aim of the present study was to investigate the metformin pharmacokinetics of a single oral dose in rats with collagen-induced arthritis (CIA). Blood and urine samples were collected at different timepoints, and analyzed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Tissue samples were also collected to investigate the expression of metabolic enzymes and drug transporters by quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and western blot. The results indicated that the bioavailability of metformin was markedly decreased in the CIA rats. Moreover, metformin was not metabolized by enzymes of rat liver microsomes, suggesting that the decreased bioavailability of metformin was independent of the liver metabolism. In addition, the mRNA, protein expression level and activity of the renal organic cation transporter 2 (OCT2) was markedly increased, suggesting that the enhanced renal clearance of metformin in CIA rats may be due to the up-regulated activity of OCT2. In conclusion, our study suggested that the reduced bioavailability of metformin in CIA rats is possibly related to the up-regulated function of the renal protein OCT2.
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Affiliation(s)
- Minghao Chen
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China; Department of Pharmacy, The First Affiliated Hospital of Jinan University (Guangzhou Overseas Chinese Hospital), Guangzhou 510630, China
| | - Guoquan You
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Cong Xie
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Ruopeng Yang
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Wanyu Hu
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Zhijie Zheng
- Clinical Pharmacology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China
| | - Shuwen Liu
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China; State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Southern Medical University, Guangzhou 510515, China.
| | - Ling Ye
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China.
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10
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Li L, Guan Z, Li R, Zhao W, Hao G, Yan Y, Xu Y, Liao L, Wang H, Gao L, Wu K, Gao Y, Li Y. Population pharmacokinetics and dosing optimization of metformin in Chinese patients with type 2 diabetes mellitus. Medicine (Baltimore) 2020; 99:e23212. [PMID: 33181704 PMCID: PMC7668473 DOI: 10.1097/md.0000000000023212] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Approximately 35% of patients fail to attain ideal initial blood glucose control under metformin monotherapy. The objective of this observational study is to simulate the optimal protocol of metformin according to the different renal function.The population pharmacokinetics of metformin was performed in 125 subjects with type 2 diabetes mellitus. Plasma concentrations of metformin were quantified by high-performance liquid chromatography. A population pharmacokinetic model of metformin was developed using NONMEN (version 7.2, Icon Development Solutions, USA). Monte Carlo simulation was used to simulate the concentration-time profiles for doses of metformin for 1000 times at different stages of renal function.The mean population pharmacokinetic parameters were apparent clearance 53.0 L/h, apparent volume of distribution 438 L, absorption rate constant 1.4 hour and lag-time 0.91 hour. Covariate analyses revealed that estimated glomerular filtration rate (eGFR) and bodyweight as individual factors influencing the apparent oral clearance: CL/F = 53.0 × ( bodyweight/75) × (eGFR/102.5)EXP(0.1797). The results of the simulation showed that patients should be prescribed metformin 2550 mg/d (t.i.d.) vs 3000 mg/d (b.i.d.) as the minimum doses for patients with augmented renal clearance.eGFR had a significant impact on metformin pharmacokinetics. Patients administered metformin twice a day require higher total daily doses than those with a regimen of 3 times a day at each stage of kidney function.
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Affiliation(s)
- Ling Li
- School of Pharmaceutical Sciences, Shandong University
| | - Ziwan Guan
- School of Pharmaceutical Sciences, Shandong University
| | - Rui Li
- School of Pharmaceutical Sciences, Shandong University
| | - Wei Zhao
- School of Pharmaceutical Sciences, Shandong University
| | - Guoxiang Hao
- School of Pharmaceutical Sciences, Shandong University
| | - Yan Yan
- School of Pharmaceutical Sciences, Shandong University
| | - Yuedong Xu
- Shandong Provincial Qianfoshan Hospital, the First Hospital Affiliated with Shandong First Medical University, Jinan
| | - Lin Liao
- Shandong Provincial Qianfoshan Hospital, the First Hospital Affiliated with Shandong First Medical University, Jinan
| | - Huanjun Wang
- Shandong Provincial Qianfoshan Hospital, the First Hospital Affiliated with Shandong First Medical University, Jinan
| | - Li Gao
- School of Pharmaceutical Sciences, Shandong University
- Shandong Provincial Qianfoshan Hospital, the First Hospital Affiliated with Shandong First Medical University, Jinan
| | - Kunrong Wu
- School of Pharmaceutical Sciences, Shandong University
| | - Yuxia Gao
- Department of Pharmacy, Shengli Hospital of Shengli Oilfield, Dongying, Shandong, China
| | - Yan Li
- School of Pharmaceutical Sciences, Shandong University
- Shandong Provincial Qianfoshan Hospital, the First Hospital Affiliated with Shandong First Medical University, Jinan
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11
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Dosage adjustment in obese children, even for common drugs, is largely unclear and a treat-to-effect approach may work best. DRUGS & THERAPY PERSPECTIVES 2020. [DOI: 10.1007/s40267-020-00734-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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12
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Krekels EHJ, Knibbe CAJ. Pharmacokinetics and Pharmacodynamics of Drugs in Obese Pediatric Patients: How to Map Uncharted Clinical Territories. Handb Exp Pharmacol 2020; 261:231-255. [PMID: 31598838 DOI: 10.1007/164_2019_250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Clinicians are increasingly faced with challenges regarding the pharmacological treatment of obese pediatric patients. To provide guidance for these treatments, a better understanding of the impact of obesity on pharmacological processes in children is needed. Results on pharmacological studies in adults show however ambiguous patterns regarding the impact of obesity on ADME processes or on drug pharmacodynamics. Additionally, based on the limited research performed in obese pediatric patients, it becomes clear that findings from obese adults cannot be expected to always translate directly to similar findings in obese children. To improve knowledge on drug pharmacology in obese pediatric patients, studies should focus on quantifying the impact of maturation, obesity, and other relevant variables on primary pharmacological parameters and on disentangling systemic (renal and/or hepatic) and presystemic (gut and/or first-pass hepatic) clearance. For this, data is required from well-designed clinical trials that include patients with not only a wide range in age but also a range in excess body weight, upon oral and intravenous dosing. Population modelling approaches are ideally suitable for this purpose and can also be used to link the pharmacokinetics to pharmacodynamics and to derive drug dosing regimens. Generalizability of research findings can be achieved by including mechanistic aspects in the data analysis, for instance, using either extrapolation approaches in population modelling or by applying physiologically based modelling principles. It is imperative that more and smarter studies are performed in obese pediatric patients to provide safe and effective treatment for this special patient population.
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Affiliation(s)
- Elke H J Krekels
- Division of Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Catherijne A J Knibbe
- Division of Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands.
- Department of Clinical Pharmacy, St. Antonius Hospital, Nieuwegein, The Netherlands.
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13
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Kyler KE, Wagner J, Hosey-Cojocari C, Watt K, Shakhnovich V. Drug Dose Selection in Pediatric Obesity: Available Information for the Most Commonly Prescribed Drugs to Children. Paediatr Drugs 2019; 21:357-369. [PMID: 31432433 PMCID: PMC7681556 DOI: 10.1007/s40272-019-00352-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Obesity rates continue to rise in children, and little guidance exists regarding the need for adjustment away from total body weight-based doses for those prescribing drugs to this population of children. A majority of drugs prescribed to children with obesity result in either sub-therapeutic or supra-therapeutic concentrations, placing these children at risk for treatment failure and drug toxicities. In this review, we highlight available obesity-specific pharmacokinetic and dosing information for the most frequently prescribed drugs to children in the inpatient and outpatient clinical settings. We also comment on available dosing recommendations for drugs prescribed to treat common pediatric obesity-related comorbidities. This review highlights that there is no safe or proven 'rule of thumb,' for dosing drugs for children with obesity, and a striking lack of pharmacokinetic data to support the creation of dosing guidelines for children with obesity for the most commonly prescribed drugs. It is important that those prescribing for children with obesity are aware of these gaps in knowledge and of potential drug treatment failure or adverse events related to drug toxicity as a result of these knowledge gaps. Until more data are available, we recommend close monitoring of drug response and adverse events in children with obesity receiving commonly prescribed drugs.
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Affiliation(s)
- Kathryn E Kyler
- Children's Mercy Kansas City, 2401 Gillham Rd., Kansas City, MO, 64108, USA.
- University of Missouri Kansas City School of Medicine, Kansas City, MO, USA.
| | - Jonathan Wagner
- Children's Mercy Kansas City, 2401 Gillham Rd., Kansas City, MO, 64108, USA
- University of Missouri Kansas City School of Medicine, Kansas City, MO, USA
| | | | - Kevin Watt
- Duke University Medical Center, Durham, NC, USA
| | - Valentina Shakhnovich
- Children's Mercy Kansas City, 2401 Gillham Rd., Kansas City, MO, 64108, USA
- University of Missouri Kansas City School of Medicine, Kansas City, MO, USA
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14
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Scherf-Clavel M, Albert E, Zieher S, Valotis A, Hickethier T, Högger P. Dried blood spot testing for estimation of renal function and analysis of metformin and sitagliptin concentrations in diabetic patients: a cross-sectional study. Eur J Clin Pharmacol 2019; 75:809-816. [PMID: 30706085 DOI: 10.1007/s00228-019-02637-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 01/21/2019] [Indexed: 12/20/2022]
Abstract
PURPOSE Dried blot spot (DBS) analysis of drugs or clinical parameters offers many advantages. We investigated the feasibility of using DBS for analysis of anti-diabetic drugs concomitantly with the estimated creatinine clearance (Clcrea). METHODS The cross-sectional study involved physicians in an enabling analysis with 70 diabetic patients and community pharmacists in a field investigation with 84 participants. All 154 DBS samples were analyzed for creatinine, metformin, and sitagliptin. RESULTS The diabetic patients revealed of a wide range of age (32-88 years), BMI values (19.8-54.7 kg/m2), and extent of polypharmacotherapy (1-21 drugs). A correlation factor to convert capillary blood creatinine from DBS into plasma concentrations was determined. Patients' Clcrea ranged from 21.6-155.9 mL/min. The results indicated statistically significant correlations (p < 0.05) between the use of two or three particular drug classes (diuretics, NSAIDs, renin-angiotensin system blockers) and a decreased renal function. DBS concentrations of metformin ranged between 0.23-4.99 μg/mL. The estimated elimination half-life (t ½) of metformin was 11.9 h in patients with a ClCrea higher than 60 mL/min and 18.5 h for diabetics with lower ClCrea. Sitagliptin capillary blood concentrations ranged between 11.12-995.6 ng/mL. Calculated t ½ of sitagliptin were 8.4 h and 13.0 h in patients with a ClCrea above and below 60 mL/min, respectively. CONCLUSIONS DBS allow for the analysis of concentrations of predominantly renally eliminated drugs and community pharmacists can provide a valuable contribution to DBS sampling.
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Affiliation(s)
- Maike Scherf-Clavel
- Institut für Pharmazie und Lebensmittelchemie, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Edwin Albert
- Gemeinschaftspraxis, Ärzte für Allgemeinmedizin, Diabetologie, Marktheidenfeld, Germany
| | - Stephan Zieher
- Gemeinschaftspraxis, Ärzte für Allgemeinmedizin, Diabetologie, Marktheidenfeld, Germany
| | - Anagnostis Valotis
- Stabsstelle Medizinsicherheit, Universitätsklinikum Würzburg, Würzburg, Germany
| | - Thomas Hickethier
- Stabsstelle Betriebsarzt, Universitätsklinikum Würzburg, Würzburg, Germany
| | - Petra Högger
- Institut für Pharmazie und Lebensmittelchemie, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
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15
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Chiew AL, Wright DFB, Roberts MS, Isbister GK. Response to 'Comment on ''Massive' metformin overdose' by Chiew et al.'. Br J Clin Pharmacol 2018; 84:2940-2941. [PMID: 30280392 PMCID: PMC6256012 DOI: 10.1111/bcp.13747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 08/13/2018] [Accepted: 08/17/2018] [Indexed: 11/30/2022] Open
Affiliation(s)
- Angela L. Chiew
- New South Wales Poisons Information CentreChildren's Hospital at WestmeadWestmeadNew South WalesAustralia
| | | | - Michael S. Roberts
- School of Pharmacy and Medical SciencesUniversity of South AustraliaAdelaideSouth AustraliaAustralia
- Translational Research Institute, Diamantina InstituteUniversity of QueenslandBrisbaneQueenslandAustralia
| | - Geoffrey K. Isbister
- New South Wales Poisons Information CentreChildren's Hospital at WestmeadWestmeadNew South WalesAustralia
- Clinical Toxicology Research GroupUniversity of NewcastleCallaghanNew South WalesAustralia
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16
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Stage TB, Wellhagen G, Christensen MMH, Guiastrennec B, Brøsen K, Kjellsson MC. Using a semi-mechanistic model to identify the main sources of variability of metformin pharmacokinetics. Basic Clin Pharmacol Toxicol 2018; 124:105-114. [DOI: 10.1111/bcpt.13139] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 09/18/2018] [Indexed: 12/19/2022]
Affiliation(s)
- Tore Bjerregaard Stage
- Clinical Pharmacology and Pharmacy; Department of Public Health; University of Southern Denmark; Odense Denmark
- Pharmacometrics Group; Department of Pharmaceutical Biosciences; Uppsala University; Uppsala Sweden
| | - Gustaf Wellhagen
- Pharmacometrics Group; Department of Pharmaceutical Biosciences; Uppsala University; Uppsala Sweden
| | | | - Benjamin Guiastrennec
- Pharmacometrics Group; Department of Pharmaceutical Biosciences; Uppsala University; Uppsala Sweden
| | - Kim Brøsen
- Clinical Pharmacology and Pharmacy; Department of Public Health; University of Southern Denmark; Odense Denmark
| | - Maria C. Kjellsson
- Pharmacometrics Group; Department of Pharmaceutical Biosciences; Uppsala University; Uppsala Sweden
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17
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Dissanayake AM, Wheldon MC, Hood CJ. Pharmacokinetics of metformin in patients with chronic kidney disease stage 4 and metformin-naïve type 2 diabetes. Pharmacol Res Perspect 2018; 6:e00424. [PMID: 30221006 PMCID: PMC6138239 DOI: 10.1002/prp2.424] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 07/09/2018] [Indexed: 01/10/2023] Open
Abstract
The pharmacokinetics of metformin therapy in patients with chronic kidney disease stage 4 (CKD-4) were studied using data from the largest Phase I consecutive cohort trial yet performed in this population. Eighteen metformin-naïve men and women with Type 2 Diabetes and creatinine clearance (CrCl) in the range 18-49 mL/min (eGFR 15-29 mL/min/1.73 m2) were allocated to daily immediate-release metformin of 250 mg, 500 mg, or 1000 mg. A first-dose profile and trough concentrations for 4 weeks were taken on all patients. Pharmacokinetic (PK) parameters were estimated by fitting a first-order compartment model with absorption in a peripheral compartment to concentrations measured 24 hours post-first dose. Single-dose PK parameters time to maximum concentration (tmax) and maximum concentration (Cmax) were consistent with previous observations in patients with normal renal function (healthy and diabetic), as was the association between CrCl and apparent total oral clearance (Cl/F). However, patients with a CrCl below 32 mL/min had trough concentrations that were consistently above the steady-state minimum implied by the population PK model. This suggests the model may not apply to patients with CrCl below 32 mL/min. Metformin in doses of 500-1000 mg/day could be taken by CKD-4 patients. However, the single-compartment model breaks down as CrCl declines below 32 mL/min suggesting that metformin levels should be monitored regularly in progressive stage 4 CKD.
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Affiliation(s)
| | - Mark C. Wheldon
- Auckland University of TechnologyAucklandNew Zealand
- Middlemore Clinical TrialsMiddlemore HospitalAucklandNew Zealand
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18
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Ningrum VD, Ikawati Z, Sadewa AH, Ikhsan MR. Patient-factors associated with metformin steady-state levels in type 2 diabetes mellitus with therapeutic dosage. J Clin Transl Endocrinol 2018; 12:42-47. [PMID: 29892566 PMCID: PMC5992324 DOI: 10.1016/j.jcte.2018.05.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 05/07/2018] [Indexed: 01/08/2023] Open
Abstract
AIMS This prospective study aimed to analyze metformin steady-state concentration in repeated constant dosage and the influencing patient-factors as well as to correlate them with glycemic control. METHODS The validated HPLC-UV method was used to examine metformin steady-state concentration, while FBG and glycated albumin were used as the parameters of glycemic control during metformin administration. RESULTS A total of 82 type-2 diabetes patients were involved with 32.1% of them having metformin Cssmin and 84.1% having Cssmax of metformin within the recommended therapeutic range. One patient had metformin Css that exceeded minimum toxic concentration despite his normal renal function and administered therapeutic dosage of metformin. Higher Cssmax was found in patients with metformin monotherapy, while patients with longer duration of metformin use had significantly higher Cssmin. CONCLUSIONS Along with initial hyperglycemia and eGFR, metformin Cssmin became the only parameter that influenced FBG level (P < 0.05). Duration of previous metformin use should be considered in the strategy of optimizing metformin dosage. The type-2 diabetes patients with obesity are more suggested to take shorter interval of metformin administration (or possibly with sustained-release formulation) to keep Cssmin within the therapeutic range.
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Affiliation(s)
| | - Zullies Ikawati
- Faculty of Pharmacy, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
| | - Ahmad H. Sadewa
- Faculty of Medicine, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
| | - Mohammad R. Ikhsan
- Department of Internal Medicine, Dr. Sardjito General Hospital, Yogyakarta 55281, Indonesia
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19
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Smit C, De Hoogd S, Brüggemann RJM, Knibbe CAJ. Obesity and drug pharmacology: a review of the influence of obesity on pharmacokinetic and pharmacodynamic parameters. Expert Opin Drug Metab Toxicol 2018; 14:275-285. [PMID: 29431542 DOI: 10.1080/17425255.2018.1440287] [Citation(s) in RCA: 124] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
INTRODUCTION The rising prevalence of obesity confronts clinicians with dosing problems in the (extreme) overweight population. Obesity has a great impact on key organs that play a role in the pharmacokinetics (PK) and pharmacodynamics (PD) of drugs, however the ultimate impact of these changes on how to adapt the dose may not always be known. Areas covered: In this review, physiological changes associated with obesity are discussed. An overview is provided on the alterations in absorption, distribution, drug metabolism and clearance in (morbid) obesity focusing on general principles that can be extracted from pharmacokinetic studies. Also, relevant pharmacodynamic considerations in obesity are discussed. Expert opinion: Over the last two decades, increased knowledge is generated on PK and PD in obesity. Future research should focus on filling in the knowledge gaps that remain, especially in connecting obesity-related physiological changes with changes in PK and/or PD and vice versa. Ultimately, this knowledge can be used to develop physiologically based PK and PD models on the basis of quantitative systems pharmacology principles. Moreover, efforts should focus on thorough prospective evaluation of developed model-based doses with subsequent implementation of these dosing recommendations in clinical practice.
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Affiliation(s)
- Cornelis Smit
- a Department of Clinical Pharmacy , St. Antonius Hospital , Nieuwegein , The Netherlands.,b Division of Pharmacology , Leiden Academic Centre for Drug Research, Leiden University , Leiden , the Netherlands
| | - Sjoerd De Hoogd
- a Department of Clinical Pharmacy , St. Antonius Hospital , Nieuwegein , The Netherlands
| | - Roger J M Brüggemann
- c Department of Pharmacy , Radboud University Medical Center , Nijmegen , The Netherlands
| | - Catherijne A J Knibbe
- a Department of Clinical Pharmacy , St. Antonius Hospital , Nieuwegein , The Netherlands.,b Division of Pharmacology , Leiden Academic Centre for Drug Research, Leiden University , Leiden , the Netherlands
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20
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Sam WJ, Roza O, Hon YY, Alfaro RM, Calis KA, Reynolds JC, Yanovski JA. Effects of SLC22A1 Polymorphisms on Metformin-Induced Reductions in Adiposity and Metformin Pharmacokinetics in Obese Children With Insulin Resistance. J Clin Pharmacol 2016; 57:219-229. [PMID: 27407018 DOI: 10.1002/jcph.796] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 07/07/2016] [Accepted: 07/09/2016] [Indexed: 12/27/2022]
Abstract
Steady-state population pharmacokinetics of a noncommercial immediate-release metformin (hydrochloride) drug product were characterized in 28 severely obese children with insulin resistance. The concentration-time profiles with double peaks were well described by a 1-compartment model with 2 absorption sites. Mean population apparent clearance (CL/F) was 68.1 L/h, and mean apparent volume of distribution (V/F) was 28.8 L. Body weight was a covariate of CL/F and V/F. Estimated glomerular filtration rate was a significant covariate of CL/F (P < .001). SLC22A1 genotype did not significantly affect metformin pharmacokinetics. The response to 6 months of metformin treatment (HbA1c , homeostasis model assessment for insulin resistance, fasting insulin, and glucose changes) did not differ between SLC22A1 wild-type subjects and carriers of presumably low-activity SLC22A1 alleles. However, SLC22A1 variant carriers had smaller reductions in percentage of total trunk fat after metformin therapy, although the percentage reduction in trunk fat was small. The median % change in trunk fat was -2.20% (-9.00% to 0.900%) and -1.20% (-2.40% to 7.30%) for the SLC22A1 wild-type subjects and variant carriers, respectively. Future study is needed to evaluate the effects of SLC22A1 polymorphisms on metformin-mediated weight reduction in obese children.
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Affiliation(s)
- Wai Johnn Sam
- Clinical Pharmacokinetics Research Laboratory, Clinical Center Pharmacy Department, National Institutes of Health, Bethesda, MD, USA
| | - Orsolya Roza
- Section on Growth and Obesity, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.,Institute of Pharmacognosy, University of Szeged, Szeged, Hungary
| | - Yuen Yi Hon
- Clinical Pharmacokinetics Research Laboratory, Clinical Center Pharmacy Department, National Institutes of Health, Bethesda, MD, USA.,Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD, USA
| | - Raul M Alfaro
- Clinical Pharmacokinetics Research Laboratory, Clinical Center Pharmacy Department, National Institutes of Health, Bethesda, MD, USA
| | - Karim A Calis
- Clinical Pharmacokinetics Research Laboratory, Clinical Center Pharmacy Department, National Institutes of Health, Bethesda, MD, USA.,Office of the Clinical Director, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - James C Reynolds
- Nuclear Medicine Division, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - Jack A Yanovski
- Section on Growth and Obesity, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
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Abstract
OBJECTIVE The aim of this study was to determine the intrapair similarity in trough steady-state plasma concentrations of metformin in monozygotic and dizygotic twin pairs. METHODS We included 16 twin pairs (eight monozygotic and eight dizygotic twin pairs) for this study after contacting 524 twin pairs. They were dosed with metformin to steady state (1 g twice daily) for 6 days and on day 7, the trough concentration of metformin was determined 12 h after the last dose. RESULTS There was no strong intrapair similarity in trough steady-state plasma concentrations of metformin in either dizygotic or monozygotic twin pairs. CONCLUSION The trough steady-state plasma concentration of metformin does not appear to be tightly genetically regulated. The interpretation of this finding is limited by the small sample size.
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Current topics on inhibitors of respiratory complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1857:884-91. [PMID: 26625959 DOI: 10.1016/j.bbabio.2015.11.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 10/26/2015] [Accepted: 11/17/2015] [Indexed: 12/12/2022]
Abstract
There are a variety of chemicals which regulate the functions of bacterial and mitochondrial complex I. Some of them, such as rotenone and piericidin A, have been indispensable molecular tools in mechanistic studies on complex I. A large amount of experimental data characterizing the actions of complex I inhibitors has been accumulated so far. Recent X-ray crystallographic structural models of entire complex I may be helpful to carefully interpret this data. We herein focused on recent hot topics on complex I inhibitors and the subjects closely connected to these inhibitors, which may provide useful information not only on the structural and functional aspects of complex I, but also on drug design targeting this enzyme. This article is part of a Special Issue entitled Respiratory complex I, edited by Volker Zickermann and Ulrich Brandt.
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Garduno LB, Salvador JN, Olguin HJ, Goytia GL, Portugal MC, Murrieta FF. Population Pharmacokinetics of Metformin in Mexican Patients with Type 2 Diabetes Mellitus. INT J PHARMACOL 2015. [DOI: 10.3923/ijp.2015.632.637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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24
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Chitnis SD, Han Y, Yamaguchi M, Mita S, Zhao R, Sunkara G, Kulmatycki K. Population pharmacokinetic modeling and noncompartmental analysis demonstrated bioequivalence between metformin component of metformin/vildagliptin fixed-dose combination products and metformin immediate-release tablet sourced from various countries. Clin Pharmacol Drug Dev 2015; 5:40-51. [PMID: 27119577 DOI: 10.1002/cpdd.191] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 02/27/2015] [Accepted: 03/19/2015] [Indexed: 01/09/2023]
Abstract
Metformin is the first-line pharmacotherapy choice for treating type-2 diabetes mellitus, alone or in combination with other antidiabetic drugs. During the development of immediate-release (IR) metformin containing novel fixed-dose combination (FDC) products, several health-authorities require sponsors to demonstrate bioequivalence between FDC products and the country-sourced metformin for market approval. Eight bioequivalence studies that compared metformin/vildagliptin FDC product (test) to metformin IR tablet sourced from various countries (reference) were conducted. A population pharmacokinetic (PPK) analysis of pooled metformin concentration-time data was performed to evaluate whether country-sourced metformin is a significant covariate. The PPK analysis demonstrated that there was no clinically relevant effect of metformin source or race/ethnicity on metformin pharmacokinetics. Also, noncompartmental analysis conducted showed that 90%CI of geometric mean ratios of test to reference metformin formulations, calculated for maximum-concentration and exposure parameters, were within the 80%-125% criteria, indicating comparable metformin exposure regardless of the country-sourced metformin IR formulation. These results are consistent with the biopharmaceutics properties of metformin and provide scientific evidence that after assessing in vitro dissolution of novel FDC formulation, additional bioequivalence studies with multiple countries' reference products may not be required once bioequivalence is established with 1 country-sourced IR metformin formulation.
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Affiliation(s)
| | - Yi Han
- Novartis Institutes for BioMedical Research, Shanghai, China
| | | | | | - Rong Zhao
- Novartis Institutes for BioMedical Research, Shanghai, China
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Abstract
Metformin is the most widely prescribed drug used to treat patients affected by Type 2 diabetes. Metformin has also been shown to prevent some forms of cell death; however, evidence suggests that it may have anti-neoplastic properties. All of these effects have been attributed to complex I inhibition, but the mechanism by which metformin leads to complex I inhibition is not fully understood. Although it has been reported that the incubation of functionally isolated complex I in the presence of high concentrations of metformin led to its inhibition, much lower concentrations of metformin have been shown to inhibit complex I in intact cells. In a recent issue of the Biochemical Journal, Bridges, Jones, Pollak and Hirst [(2014) Biochem. J. 462, 475-487] studied for the first time the effect of metformin on purified complex I. They report that millimolar concentrations of metformin directly inhibit complex I activity in a non-competitive manner. They also specify that the binding of metformin to complex I depends on its conformation. To explain the difference in concentration required to inhibit complex I in intact cells and on isolated enzyme, Bridges et al. (2014) propose that metformin concentrates within mitochondria in intact cells. Albeit theoretically plausible, this attractive hypothesis is not directly tested by Bridges et al. (2014) Moreover, although sparse, the current literature does not support this hypothesis.
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Abstract
Metformin is the most commonly prescribed medication for type 2 diabetes (T2DM) in the world. It has primacy in the treatment of this disease because of its safety record and also because of evidence for reduction in the risk of cardiovascular events. Evidence has accumulated indicating that metformin is safe in people with stage 3 chronic kidney disease (CKD-3). It is estimated that roughly one-quarter of people with CKD-3 and T2DM in the United States (well over 1 million) are ineligible for metformin treatment because of elevated serum creatinine levels. This could be overcome if a scheme, perhaps based on pharmacokinetic studies, could be developed to prescribe reduced doses of metformin in these individuals. There is also substantial evidence from epidemiologic studies to indicate that metformin may not only be safe, but may actually benefit people with heart failure (HF). Prospective, randomized trials of the use of metformin in HF are needed to investigate this possibility.
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Affiliation(s)
- John M. Miles
- To whom correspondence should be addressed. Telephone 507 284 3289; Fax 507 255 4828
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Use of biguanides to improve response to chemotherapy. Methods Mol Biol 2014; 1165:3-9. [PMID: 24839014 DOI: 10.1007/978-1-4939-0856-1_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Metformin is a commonly utilized antidiabetic agent, which has been associated with improved clinical outcomes in cancer patients. The precise mechanism of action remains unclear, but preclinical evidence suggests that metformin can sensitize tumor cells to the effects to conventional chemotherapeutic agents and ionizing radiation (IR). In this chapter we discuss the general background of an approach to evaluate the effects of metformin on conventional chemotherapeutic agent toxicity in a preclinical model.
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Lalau JD, Arnouts P, Sharif A, De Broe ME. Metformin and other antidiabetic agents in renal failure patients. Kidney Int 2014; 87:308-22. [PMID: 24599253 DOI: 10.1038/ki.2014.19] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 11/21/2013] [Accepted: 12/12/2013] [Indexed: 12/11/2022]
Abstract
This review mainly focuses on metformin, and considers oral antidiabetic therapy in kidney transplant patients and the potential benefits and risks of antidiabetic agents other than metformin in patients with chronic kidney disease (CKD). In view of the debate concerning lactic acidosis associated with metformin, this review tries to solve a paradox: metformin should be prescribed more widely because of its beneficial effects, but also less widely because of the increasing prevalence of contraindications to metformin, such as reduced renal function. Lactic acidosis appears either as part of a number of clinical syndromes (i.e., unrelated to metformin), induced by metformin (involving an analysis of the drug's pharmacokinetics and mechanisms of action), or associated with metformin (a more complex situation, as lactic acidosis in a metformin-treated patient is not necessarily accompanied by metformin accumulation, nor does metformin accumulation necessarily lead to lactic acidosis). A critical analysis of guidelines and literature data on metformin therapy in patients with CKD is presented. Following the present focus on metformin, new paradoxical issues can be drawn up, in particular: (i) metformin is rarely the sole cause of lactic acidosis; (ii) lactic acidosis in patients receiving metformin therapy is erroneously still considered a single medical entity, as several different scenarios can be defined, with contrasting prognoses. The prognosis for severe lactic acidosis seems even better in metformin-treated patients than in non-metformin users.
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Affiliation(s)
- Jean-Daniel Lalau
- 1] Service d'Endocrinologie et de Nutrition, Centre Hospitalier Universitaire, Amiens, France [2] Unité INSERM U-1088, Université de Picardie Jules Verne, Amiens, France
| | - Paul Arnouts
- Department of Nephrology-Diabetology-Endocrinology, AZ Turnhout, Turnhout, Belgium
| | - Adnan Sharif
- Department of Nephrology and Transplantation, Renal Institute of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Marc E De Broe
- Laboratory of Pathophysiology, University of Antwerp, Wilrijk, Belgium
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Yang JS, Oh HJ, Jung JA, Kim JR, Kim TE, Ko JW, Lee SY, Huh W. Pentafluorophenylprophyl Ligand-based Liquid Chromatography-Tandem Mass Spectrometric Method for Rapid and Reproducible Determination of Metformin in Human Plasma. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.11.3284] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Duong JK, Kumar SS, Kirkpatrick CM, Greenup LC, Arora M, Lee TC, Timmins P, Graham GG, Furlong TJ, Greenfield JR, Williams KM, Day RO. Population pharmacokinetics of metformin in healthy subjects and patients with type 2 diabetes mellitus: simulation of doses according to renal function. Clin Pharmacokinet 2013; 52:373-84. [PMID: 23475568 DOI: 10.1007/s40262-013-0046-9] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND OBJECTIVE Metformin is contraindicated in patients with renal impairment; however, there is poor adherence to current dosing guidelines. In addition, the pharmacokinetics of metformin in patients with significant renal impairment are not well described. The aims of this study were to investigate factors influencing the pharmacokinetic variability, including variant transporters, between healthy subjects and patients with type 2 diabetes mellitus (T2DM) and to simulate doses of metformin at varying stages of renal function. METHODS Plasma concentrations of metformin were pooled from three studies: patients with T2DM (study A; n = 120), healthy Caucasian subjects (study B; n = 16) and healthy Malaysian subjects (study C; n = 169). A population pharmacokinetic model of metformin was developed using NONMEM(®) version VI for both the immediate-release (IR) formulation and the extended-release (XR) formulation of metformin. Total body weight (TBW), lean body weight (LBW), creatinine clearance (CLCR; estimated using TBW and LBW) and 57 single-nucleotide polymorphisms (SNPs) of metformin transporters (OCT1, OCT2, OCT3, MATE1 and PMAT) were investigated as potential covariates. A nonparametric bootstrap (n = 1,000) was used to evaluate the final model. This model was used to simulate 1,000 concentration-time profiles for doses of metformin at each stage of renal impairment to ensure metformin concentrations do not exceed 5 mg/l, the proposed upper limit. RESULTS Creatinine clearance and TBW were clinically and statistically significant covariates with the apparent clearance and volume of distribution of metformin, respectively. None of the 57 SNPs in transporters of metformin were significant covariates. In contrast to previous studies, there was no effect on the pharmacokinetics of metformin in patients carrying the reduced function OCT1 allele (R61C, G401S, 420del or G465R). Dosing simulations revealed that the maximum daily doses in relation to creatinine clearance to prescribe to patients are 500 mg (15 ml/min), 1,000 mg (30 ml/min), 2,000 mg (60 ml/min) and 3,000 mg (120 ml/min), for both the IR and XR formulations. CONCLUSION The population model enabled doses of metformin to be simulated for each stage of renal function, to ensure the concentrations of metformin do not exceed 5 mg/l. However, the plasma concentrations of metformin at these dosage levels are still quite variable and monitoring metformin concentrations may be of value in individualising dosage. This study provides confirmatory data that metformin can be used, with appropriate dosage adjustment, in patients with renal impairment.
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Affiliation(s)
- Janna K Duong
- School of Medical Sciences, University of New South Wales, Kensington, Sydney, NSW, Australia
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Abstract
The high rate of negative clinical trials and failed drug development programs calls into question the use of preclinical testing as currently practiced. An important issue for the in vitro testing of agents that have advanced into the clinic is the use of clinically irrelevant concentrations in reports making claims for anticancer activity, as illustrated by publications for sorafenib, vorinostat, and metformin. For sorafenib, high protein binding leads to a dichotomy between concentrations active in the 10% serum conditions commonly used for in vitro testing and concentrations active in plasma. Failure to recognize this distinction leads to inappropriate claims of activity for sorafenib based on the micromolar concentrations commonly used for in vitro testing in low serum conditions. For vorinostat and metformin, results using in vitro concentrations higher than those achievable in patients are reported despite the availability of publications describing human pharmacokinetic data for each agent. We encourage journal editors and reviewers to pay greater attention to clinically relevant concentrations when considering reports that include in vitro testing of agents for which human pharmacokinetic data are available. Steps taken to more carefully scrutinize activity claims based on in vitro results can help direct researchers away from clinically irrelevant lines of research and toward lines of research that are more likely to lead to positive clinical trials and to improved treatments for patients with cancer.
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Affiliation(s)
- Malcolm A Smith
- Cancer Therapy Evaluation Program, National Cancer Institute, Bethesda, Maryland 20892, USA.
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Yoon H, Cho HY, Yoo HD, Kim SM, Lee YB. Influences of organic cation transporter polymorphisms on the population pharmacokinetics of metformin in healthy subjects. AAPS JOURNAL 2013; 15:571-80. [PMID: 23417334 DOI: 10.1208/s12248-013-9460-z] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 01/28/2013] [Indexed: 01/13/2023]
Abstract
This study investigated the effects of genetic polymorphisms in organic cation transporter (OCT) genes, such as OCT1-3, OCTN1, MATE1, and MATE2-K, on metformin pharmacokinetics. Of particular interest was the influence of genetic polymorphisms as covariates on the variability in the population pharmacokinetics (PPK) of metformin using nonlinear mixed effects modeling (NONMEM). In a retrospective data analysis, data on subjects from five independent metformin bioequivalence studies that used the same protocol were assembled and compared with 96 healthy control subjects who were administered a single oral 500 mg dose of metformin. Genetic polymorphisms of OCT2-808 G>T and OCTN1-917C>T had a significant (P<0.05) effect on metformin pharmacokinetics, yielding a higher peak concentration with a larger area under the serum time-concentration curve. The values obtained were 102±34.5 L/h for apparent oral clearance (CL/F), 447±214 L for volume of distribution (V d/F), and 3.1±0.9 h for terminal half-life (mean±SD) by non-compartmental analysis. The NONMEM method gives similar results. The metformin serum levels were obtained by setting the one-compartment model to a first-order absorption and lag time. In the PPK model, the effects of OCT2-808 G>T and OCTN1-917C>T variants on the CL/F were significant (P<0.001 and P<0.05, respectively). Thus, genetic variants of OCTN1-917C>T, along with OCT2-808 G>T genetic polymorphisms, could be useful in titrating the optimal metformin dose.
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Affiliation(s)
- Hwa Yoon
- College of Pharmacy and Institute of Bioequivalence and Bridging Study, Chonnam National University, 300 Yongbong-Dong, Gwangju, 500-757, South Korea
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