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Fagerberg JH, Sjögren E, Bergström CA. Concomitant intake of alcohol may increase the absorption of poorly soluble drugs. Eur J Pharm Sci 2015; 67:12-20. [DOI: 10.1016/j.ejps.2014.10.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 10/23/2014] [Indexed: 10/24/2022]
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Bhoopathy S, Bode C, Naageshwaran V, Weiskircher-Hildebrandt EA, Hidalgo IJ. Case study 6. Transporter case studies: in vitro solutions for translatable outcomes. Methods Mol Biol 2014; 1113:485-511. [PMID: 24523127 DOI: 10.1007/978-1-62703-758-7_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Assessing the interactions of a new drug candidate with transporters, either as a substrate or as an inhibitor, is no simple matter. There are many clinically relevant transporters, as many as nine to be evaluated for an FDA submission and up to eleven for the EMA as of 2013. Additionally, it is likely that if a compound is a substrate or inhibitor of one transporter, it will be so for other transporters as well. There are practically no specific substrates or inhibitors, presumably because the specificities of drug transporters are so broad and overlapping, and even fewer clinically relevant probes that can be used to evaluate transporter function in humans. In the case of some transporters, it is advisable to evaluate an NCE with more than one test system and/or more than one probe substrate in order to convince oneself (and regulatory authorities) that a clinical drug interaction study is not warranted. Finally, each test system has its own unique set of advantages and disadvantages. One has to really appreciate the nuances of the available tools (test systems, probe substrates, etc.) to select the best tools for the job and design the optimal in vitro experiment. In this chapter, several examples are used to illustrate the successful interpretation of in vitro data for both efflux and uptake transporters. Some data presented in this chapter is unpublished at the time of compilation of this book. It has been incorporated in this chapter to provide a sense of complexities in transporter kinetics to the reader.
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Affiliation(s)
- Sid Bhoopathy
- Absorption Systems LP, 436 Creamery Way, Suite 600, Exton, PA, USA
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van Duijn E, Sandman H, Grossouw D, Mocking JAJ, Coulier L, Vaes WHJ. Automated Combustion Accelerator Mass Spectrometry for the Analysis of Biomedical Samples in the Low Attomole Range. Anal Chem 2014; 86:7635-41. [DOI: 10.1021/ac5015035] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | - Hugo Sandman
- TNO, P.O. Box 360, 3700AJ Zeist, The Netherlands
| | | | | | - Leon Coulier
- TNO, P.O. Box 360, 3700AJ Zeist, The Netherlands
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Poirier A, Cascais AC, Bader U, Portmann R, Brun ME, Walter I, Hillebrecht A, Ullah M, Funk C. Calibration of In Vitro Multidrug Resistance Protein 1 Substrate and Inhibition Assays as a Basis to Support the Prediction of Clinically Relevant Interactions In Vivo. Drug Metab Dispos 2014; 42:1411-22. [DOI: 10.1124/dmd.114.057943] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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Sjögren E, Hedeland M, Bondesson U, Lennernäs H. Effects of verapamil on the pharmacokinetics and hepatobiliary disposition of fexofenadine in pigs. Eur J Pharm Sci 2014; 57:214-23. [PMID: 24075962 DOI: 10.1016/j.ejps.2013.09.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 08/19/2013] [Accepted: 09/18/2013] [Indexed: 11/29/2022]
Abstract
The pharmacokinetics (PK) of fexofenadine (FEX) in pigs were investigated with the focus on exploring the interplay between hepatic transport and metabolism when administered intravenously (iv) alone or with verapamil. The in vivo pig model enabled simultaneous sampling from plasma (pre-liver, post-liver and peripheral), bile and urine. Each animal was administered FEX 35mg iv alone or with verapamil 35mg. Plasma, bile and urine were analyzed with liquid chromatography-tandem mass spectrometry. Non-compartmental analysis (NCA) was used to estimate traditional PK parameters. In addition, a physiologically based pharmacokinetic (PBPK) model consisting of 11 compartments (6 tissues +5 sample sites) was applied for mechanistic elucidation and estimation of individual PK parameters. FEX had a terminal half-life of 1.7h and a liver extraction of 3%. The fraction of the administered dose of unchanged FEX excreted into the bile was 25% and the bile exposure was more than 100 times higher than the portal vein total plasma exposure, indicating carrier-mediated (CM) disposition processes in the liver. 23% of the administered dose of FEX was excreted unchanged in the urine. An increase in FEX plasma exposure (+50%) and a decrease in renal clearance (-61%) were detected by NCA as a direct effect of concomitant administration of verapamil. However, analysis of the PBPK model also revealed that biliary clearance was significantly inhibited (-53%) by verapamil. In addition, PBPK analysis established that metabolism and CM uptake were important factors in the disposition of FEX in the liver. In conclusion, this study demonstrated that CM transport of FEX in both liver and kidneys was inhibited by a single dose of verapamil.
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Affiliation(s)
- Erik Sjögren
- Department of Pharmacy, Biopharmaceutic Research Group, Uppsala University, Box 580, SE-751 23 Uppsala, Sweden.
| | - Mikael Hedeland
- Department of Medicinal Chemistry, Division of Analytical Pharmaceutical Chemistry, Uppsala University, Box 573, SE-751 23 Uppsala, Sweden; National Veterinary Institute (SVA), Department of Chemistry, Environment and Feed Hygiene, SE-751 89 Uppsala, Sweden
| | - Ulf Bondesson
- Department of Medicinal Chemistry, Division of Analytical Pharmaceutical Chemistry, Uppsala University, Box 573, SE-751 23 Uppsala, Sweden; National Veterinary Institute (SVA), Department of Chemistry, Environment and Feed Hygiene, SE-751 89 Uppsala, Sweden
| | - Hans Lennernäs
- Department of Pharmacy, Biopharmaceutic Research Group, Uppsala University, Box 580, SE-751 23 Uppsala, Sweden
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Martinez JM, Khier S, Morita S, Rauch C, Fabre D. Population pharmacokinetic analysis of fexofenadine in Japanese pediatric patients. J Pharmacokinet Pharmacodyn 2014; 41:187-95. [PMID: 24633780 DOI: 10.1007/s10928-014-9356-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 03/06/2014] [Indexed: 11/28/2022]
Abstract
A population pharmacokinetic analysis was conducted to characterize the pharmacokinetics of fexofenadine in Japanese pediatric patients (6 months through 16 years) with perennial allergic rhinitis or atopic dermatitis. The dataset was composed of 515 patients (including 109 adults), for a total of 1,080 concentration-time points. The analysis was performed with NONMEM using the SAEM method. Several structural models and residual error models were evaluated. The relationship between the individual estimates and the potential covariates was then investigated: demographic and pathophysiologic characteristics were tested as potential model covariates (forward selection method). The qualification of the model was performed using visual predictive check and bootstrap. A two-compartment disposition model with first-order absorption best fitted the data. The inter-individual variability was modeled through an exponential error model for all parameters (except for ka for which no inter-individual term could be estimated), while a proportional error model was used to model the residual variability. The final model included two covariates on elimination clearance and one on the intercompartmental clearance. CL/F was related to BSA and patient's age (expressed in months) Q/F was also related to BSA. Once the model was correctly qualified, exposure parameters such as Cmax and AUCτ were computed and compared between each age sub-group and between Japanese and Caucasians patients. These comparisons did not reveal any major difference (less than 50 %) between subgroups.
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Affiliation(s)
- Jean-Marie Martinez
- Disposition, Safety and Animal Research, Drug Disposition, Modeling and Simulations Entity, Sanofi-aventis Recherche & Développement, 371, rue du Professeur Joseph Blayac, 34184, Montpellier Cedex 04, France,
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57
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Yehia SA, El-Ridi MS, Tadros MI, El-Sherif NG. Phenylalanine-free taste-masked orodispersible tablets of fexofenadine hydrochloride: development,in vitroevaluation andin vivoestimation of the drug pharmacokinetics in healthy human volunteers. Pharm Dev Technol 2014; 20:528-39. [DOI: 10.3109/10837450.2014.882942] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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58
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Schwab D, Portron A, Backholer Z, Lausecker B, Kawashima K. A novel double-tracer technique to characterize absorption, distribution, metabolism and excretion (ADME) of [14C]tofogliflozin after oral administration and concomitant intravenous microdose administration of [13C]tofogliflozin in humans. Clin Pharmacokinet 2013; 52:463-73. [PMID: 23494983 DOI: 10.1007/s40262-013-0051-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Human mass balance studies and the assessment of absolute oral bioavailability (F) are usually assessed in separate studies. Intravenous microdose administration of an isotope tracer concomitant to an unlabeled oral dose is an emerging technique to assess F. We report a novel double-tracer approach implemented for tofogliflozin combining oral administration of a radiolabel tracer with concomitant intravenous administration of a stable isotope tracer. Tofogliflozin is a potent and selective sodium/glucose cotransporter 2 inhibitor for the treatment of type 2 diabetes mellitus currently in clinical development. OBJECTIVES The objectives of the present study were to assess the systemic exposure of major circulating metabolites, excretion balance, F and contribution of renal clearance (CLR) to total clearance (CL) of tofogliflozin in healthy subjects within one study applying a novel double-tracer technique. METHODS Six healthy male subjects received 20 mg [(12)C/(14)C]tofogliflozin (3.73 MBq) orally and a concomitant microdose of 0.1 mg [(13)C]tofogliflozin intravenously. Pharmacokinetics of tofogliflozin were determined for the oral and intravenous route; the pharmacokinetics of the metabolites M1 and M5 were determined for the oral route. Quantification of [(12)C]tofogliflozin in plasma and urine and [(13)C]tofogliflozin in plasma was performed by selective LC-MS/MS methods. For the pre-selected metabolites of tofogliflozin, M1 and M5, a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) was applied to plasma and urine samples. Total radioactivity was assessed in plasma, urine and feces. Pharmacokinetic analysis was conducted by non-compartmental methods. RESULTS The pharmacokinetics of tofogliflozin in healthy subjects were characterized by an F of 97.5 ± 12.3 %, CL of 10.0 ± 1.3 l/h and volume of distribution at steady-state (V(ss)) of 50.6 ± 6.7 l. The main route of elimination of total drug-related material was by excretion into urine (77.0 ± 4.1 % of the dose). The observed CL(R) of 25.7 ± 5.0 ml/min was higher than the product of the estimated glomerular filtration rate (eGFR) and fraction unbound in plasma (f(u)) (eGFR × f(u) 15 ml/min), indicating the presence of net active tubular secretion in the renal elimination of tofogliflozin. However, CLR contributed only 15.5 % to the CL of tofogliflozin, suggesting that reductions in CLR by renal impairment won't significantly affect systemic exposure to tofogliflozin. Tofogliflozin and its metabolite M1 were the only major circulating entities accounting for 46 ± 8.6 and 50 ± 8.2 %, respectively, of total circulating drug-related material, while the metabolite M5 was a minor circulating metabolite accounting for 3.0 ± 0.3 % of total circulating drug-related material. Both the M1 and M5 metabolites were excreted into urine and the major metabolite M1 did not exhibit active tubular secretion. CONCLUSIONS These results demonstrate the utility of the double-tracer approach to provide essential pharmacokinetic data and excretion data for drug-related material in one study at the same dosing occasion. The data obtained allowed the characterization of absorption, distribution, metabolism and excretion of tofogliflozin. Tofogliflozin exhibited highly favorable pharmacokinetic properties as demonstrated by its high F, low CL and a low V(ss. The presence of only one major circulating metabolite of tofogliflozin was unambiguously demonstrated. As a drug targeting the kidney, luminal exposure of the kidney is achieved by renal filtration and active tubular secretion.
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Affiliation(s)
- Dietmar Schwab
- pRED Clinical Pharmacology, F Hoffmann-La Roche AG, Bldg 663/2130, 4070 Basel, Switzerland.
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59
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Lennernäs H. Human in vivo regional intestinal permeability: importance for pharmaceutical drug development. Mol Pharm 2013; 11:12-23. [PMID: 24206063 DOI: 10.1021/mp4003392] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Both the development and regulation of pharmaceutical dosage forms have undergone significant improvements and development over the past 25 years, due primarily to the extensive application of the biopharmaceutical classification system (BCS). The Biopharmaceutics Drug Disposition Classification System, which was published in 2005, has also been a useful resource for predicting the influence of transporters in several pharmacokinetic processes. However, there remains a need for the pharmaceutical industry to develop reliable in vitro/in vivo correlations and in silico methods for predicting the rate and extent of complex gastrointestinal (GI) absorption, the bioavailability, and the plasma concentration-time curves for orally administered drug products. Accordingly, a more rational approach is required, one in which high quality in vitro or in silico characterizations of active pharmaceutical ingredients and formulations are integrated into physiologically based in silico biopharmaceutics models to capture the full complexity of GI drug absorption. The need for better understanding of the in vivo GI process has recently become evident after an unsuccessful attempt to predict the GI absorption of BCS class II and IV drugs. Reliable data on the in vivo permeability of the human intestine (Peff) from various intestinal regions is recognized as one of the key biopharmaceutical requirements when developing in silico GI biopharmaceutics models with improved predictive accuracy. The Peff values for human jejunum and ileum, based on historical open, single-pass, perfusion studies are presented in this review. The main objective of this review is to summarize and discuss the relevance and current status of these human in vivo regional intestinal permeability values.
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Affiliation(s)
- Hans Lennernäs
- Department of Pharmaceutics, Uppsala University , 753 12 Uppsala, Sweden
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Iodine-129 microdosing for protein and peptide drug development: erythropoietin as a case study. Bioanalysis 2013; 5:53-63. [PMID: 23256472 DOI: 10.4155/bio.12.297] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Microdosing is a technique for studying the behavior of compounds in vivo at 1/100th of the dose of a test substance calculated, based on animal data, to yield a pharmacologic effect. In microdosing, use is made of accelerator MS (AMS). In this study, we investigated whether (129)I-labeling of proteins with subsequent AMS measurements is a suitable method to perform microdose studies with therapeutic proteins. We used erythropoietin (EPO) as a case study. RESULTS In an animal study with (129)I-labeled EPO in Han-Wistar rats, an increase of (129)I-EPO is observed after dose administration. The half-life was found to be 2 and 5.5 h for two different EPOs. These results are in accordance with expected values. CONCLUSION Although further research is required, (129)I-labeling of proteins seems a feasible method for AMS microdose studies with peptide and protein drugs, such as biosimilars.
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Boulton DW, Kasichayanula S, Keung CFA, Arnold ME, Christopher LJ, Xu XS, Lacreta F. Simultaneous oral therapeutic and intravenous ¹⁴C-microdoses to determine the absolute oral bioavailability of saxagliptin and dapagliflozin. Br J Clin Pharmacol 2013; 75:763-8. [PMID: 22823746 DOI: 10.1111/j.1365-2125.2012.04391.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 07/08/2012] [Indexed: 11/27/2022] Open
Abstract
AIM To determine the absolute oral bioavailability (F(p.o.) ) of saxagliptin and dapagliflozin using simultaneous intravenous ¹⁴C-microdose/therapeutic oral dosing (i.v.micro + oraltherap). METHODS The F(p.o.) values of saxagliptin and dapagliflozin were determined in healthy subjects (n = 7 and 8, respectively) following the concomitant administration of single i.v. micro doses with unlabelled oraltherap doses. Accelerator mass spectrometry and liquid chromatography-tandem mass spectrometry were used to quantify the labelled and unlabelled drug, respectively. RESULTS The geometric mean point estimates (90% confidence interval) F(p.o) . values for saxagliptin and dapagliflozin were 50% (48, 53%) and 78% (73, 83%), respectively. The i.v.micro had similar pharmacokinetics to oraltherap. CONCLUSIONS Simultaneous i.v.micro + oraltherap dosing is a valuable tool to assess human absolute bioavailability.
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Affiliation(s)
- David W Boulton
- Bristol-Myers Squibb Research and Development, Princeton, New Jersey, USA.
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62
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Denton CL, Minthorn E, Carson SW, Young GC, Richards-Peterson LE, Botbyl J, Han C, Morrison RA, Blackman SC, Ouellet D. Concomitant Oral and Intravenous Pharmacokinetics of Dabrafenib, a BRAF Inhibitor, in Patients with BRAF V600 Mutation-Positive Solid Tumors. J Clin Pharmacol 2013; 53:955-61. [DOI: 10.1002/jcph.127] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Accepted: 06/04/2013] [Indexed: 11/09/2022]
Affiliation(s)
| | | | | | | | | | | | - Chao Han
- Biologics Clinical Pharmacology; Janssen R&D; Spring House PA USA
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63
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Shitara Y, Maeda K, Ikejiri K, Yoshida K, Horie T, Sugiyama Y. Clinical significance of organic anion transporting polypeptides (OATPs) in drug disposition: their roles in hepatic clearance and intestinal absorption. Biopharm Drug Dispos 2013; 34:45-78. [PMID: 23115084 DOI: 10.1002/bdd.1823] [Citation(s) in RCA: 306] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Organic anion transporting polypeptide (OATP) family transporters accept a number of drugs and are increasingly being recognized as important factors in governing drug and metabolite pharmacokinetics. OATP1B1 and OATP1B3 play an important role in hepatic drug uptake while OATP2B1 and OATP1A2 might be key players in intestinal absorption and transport across blood-brain barrier of drugs, respectively. To understand the importance of OATPs in the hepatic clearance of drugs, the rate-determining process for elimination should be considered; for some drugs, hepatic uptake clearance rather than metabolic intrinsic clearance is the more important determinant of hepatic clearances. The importance of the unbound concentration ratio (liver/blood), K(p,uu) , of drugs, which is partly governed by OATPs, is exemplified in interpreting the difference in the IC(50) of statins between the hepatocyte and microsome systems for the inhibition of HMG-CoA reductase activity. The intrinsic activity and/or expression level of OATPs are affected by genetic polymorphisms and drug-drug interactions. Their effects on the elimination rate or intestinal absorption rate of drugs may sometimes depend on the substrate drug. This is partly because of the different contribution of OATP isoforms to clearance or intestinal absorption. When the contribution of the OATP-mediated pathway is substantial, the pharmacokinetics of substrate drugs should be greatly affected. This review describes the estimation of the contribution of OATP1B1 to the total hepatic uptake of drugs from the data of fold-increases in the plasma concentration of substrate drugs by the genetic polymorphism of this transporter. To understand the importance of the OATP family transporters, modeling and simulation with a physiologically based pharmacokinetic model are helpful.
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Affiliation(s)
- Yoshihisa Shitara
- Pharmacokinetics Laboratory, Pharmaceutical Research Center, Meiji Seika Pharma Co., Ltd, Yokohama, Japan
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Sjögren E, Westergren J, Grant I, Hanisch G, Lindfors L, Lennernäs H, Abrahamsson B, Tannergren C. In silico predictions of gastrointestinal drug absorption in pharmaceutical product development: Application of the mechanistic absorption model GI-Sim. Eur J Pharm Sci 2013; 49:679-98. [DOI: 10.1016/j.ejps.2013.05.019] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 04/24/2013] [Accepted: 05/14/2013] [Indexed: 01/28/2023]
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65
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Modeling of PET data in CNS drug discovery and development. J Pharmacokinet Pharmacodyn 2013; 40:267-79. [PMID: 23660778 DOI: 10.1007/s10928-013-9320-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 04/26/2013] [Indexed: 12/22/2022]
Abstract
Positron emission tomography (PET) is increasingly used in drug discovery and development for evaluation of CNS drug disposition and for studies of disease biomarkers to monitor drug effects on brain pathology. The quantitative analysis of PET data is based on kinetic modeling of radioactivity concentrations in plasma and brain tissue compartments. A number of quantitative methods of analysis have been developed that allow the determination of parameters describing drug pharmacokinetics and interaction with target binding sites in the brain. The optimal method of quantification depends on the properties of the radiolabeled drug or radioligand and the binding site studied. We here review the most frequently used methods for quantification of PET data in relation to CNS drug discovery and development. The utility of PET kinetic modeling in the development of novel CNS drugs is illustrated by examples from studies of the brain kinetic properties of radiolabeled drug molecules.
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Lappin G, Noveck R, Burt T. Microdosing and drug development: past, present and future. Expert Opin Drug Metab Toxicol 2013; 9:817-34. [PMID: 23550938 DOI: 10.1517/17425255.2013.786042] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
INTRODUCTION Microdosing is an approach to early drug development where exploratory pharmacokinetic data are acquired in humans using inherently safe sub-pharmacologic doses of drug. The first publication of microdose data was 10 years ago and this review comprehensively explores the microdose concept from conception, over the past decade, up until the current date. AREAS COVERED The authors define and distinguish the concept of microdosing from similar approaches. The authors review the ability of microdosing to provide exploratory pharmacokinetics (concentration-time data) but exclude microdosing using positron emission tomography. The article provides a comprehensive review of data within the peer-reviewed literature as well as the latest applications and a look into the future, towards where microdosing may be headed. EXPERT OPINION Evidence so far suggests that microdosing may be a better predictive tool of human pharmacokinetics than alternative methods and combination with physiologically based modelling may lead to much more reliable predictions in the future. The concept has also been applied to drug-drug interactions, polymorphism and assessing drug concentrations over time at its site of action. Microdosing may yet have more to offer in unanticipated directions and provide benefits that have not been fully realised to date.
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Affiliation(s)
- Graham Lappin
- University of Lincoln, Brayford Pool, Lincoln, LN6 7TS, UK.
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67
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Ieiri I, Doi Y, Maeda K, Sasaki T, Kimura M, Hirota T, Chiyoda T, Miyagawa M, Irie S, Iwasaki K, Sugiyama Y. Microdosing Clinical Study: Pharmacokinetic, Pharmacogenomic (SLCO2B1), and Interaction (Grapefruit Juice) Profiles of Celiprolol Following the Oral Microdose and Therapeutic Dose. J Clin Pharmacol 2013; 52:1078-89. [DOI: 10.1177/0091270011408612] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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68
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Ieiri I, Tsunemitsu S, Maeda K, Ando Y, Izumi N, Kimura M, Yamane N, Okuzono T, Morishita M, Kotani N, Kanda E, Deguchi M, Matsuguma K, Matsuki S, Hirota T, Irie S, Kusuhara H, Sugiyama Y. Mechanisms of pharmacokinetic enhancement between ritonavir and saquinavir; micro/small dosing tests using midazolam (CYP3A4), fexofenadine (p-glycoprotein), and pravastatin (OATP1B1) as probe drugs. J Clin Pharmacol 2013; 53:654-61. [PMID: 23381882 DOI: 10.1002/jcph.62] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 12/05/2012] [Indexed: 11/08/2022]
Abstract
We investigated the mechanisms of ritonavir-mediated enhancement effect on the pharmacokinetics of saquinavir using in vivo probes for CYP3A4 (midazolam), p-glycoprotein (fexofenadine), and OATP1B1 (pravastatin) following oral micro/small dosing. A cocktail of the drugs (2 mg of saquinavir, 100 µg of each probe) was administered to eight healthy volunteers (phase 1), and then coadministered with 20 mg (phase 2) and 100 mg (phase 3) of ritonavir. Plasma concentrations of the drugs were measured by validated LC-MS/MS methods. The mean plasma AUC0-24 (pg hour/mL) of saquinavir at phases 1, 2, and 3 was 101, 2 540, and 23 900 (P < .01), respectively. The relative area under the plasma concentration-time curve (AUC)0-24 ratios of midazolam and fexofenadine at phases 1, 2, and 3 were 1:5.9:14.7 (P < .01), and 1:1.4:2.2 (P < .01-.05), respectively. In contrast, there was no difference in the pharmacokinetics of pravastatin. Inhibition of intestinal and hepatic CYP3A-mediated metabolism, and intestinal p-glycoprotein-mediated efflux of saquinavir, but not OATP1B1, is involved in the enhancement mechanism. Micro/small dosing is useful for examining the mechanism of drug interactions without safety concern.
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Affiliation(s)
- Ichiro Ieiri
- Department of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
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69
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Rowland M. Microdosing: A Critical Assessment of Human Data. J Pharm Sci 2012; 101:4067-74. [DOI: 10.1002/jps.23290] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 07/06/2012] [Accepted: 07/20/2012] [Indexed: 11/09/2022]
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70
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Kusuhara H, Miura M, Yasui-Furukori N, Yoshida K, Akamine Y, Yokochi M, Fukizawa S, Ikejiri K, Kanamitsu K, Uno T, Sugiyama Y. Effect of Coadministration of Single and Multiple Doses of Rifampicin on the Pharmacokinetics of Fexofenadine Enantiomers in Healthy Subjects. Drug Metab Dispos 2012; 41:206-13. [DOI: 10.1124/dmd.112.048330] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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71
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Ohura K, Soejima T, Nogata R, Adachi Y, Ninomiya SI, Imai T. Effect of intestinal first-pass hydrolysis on the oral bioavailability of an ester prodrug of fexofenadine. J Pharm Sci 2012; 101:3264-74. [PMID: 22628163 DOI: 10.1002/jps.23182] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 04/12/2012] [Accepted: 04/18/2012] [Indexed: 12/24/2022]
Abstract
The contribution of intestinal first-pass hydrolysis to oral bioavailability was evaluated in rats using a model prodrug of fexofenadine (FXD), which has poor oral bioavailability. The prodrug, ethyl-FXD, has high membrane permeability but the oral bioavailability of FXD derived from ethyl-FXD was only 6.2%. Ethyl-FXD was not detected in the plasma, whereas FXD was detected, indicating complete first-pass hydrolysis. In in vitro experiments, hydrolase activity for ethyl-FXD was higher in the liver and blood than that in the intestine. However, the high blood protein binding of ethyl-FXD resulted in a high hepatic availability (F(h) = 88%). The complete bioconversion of ethyl-FXD in the in vivo oral administration is difficult to explain by first-pass hydrolysis in the liver and blood. Interestingly, in an in situ rat jejunal single-pass perfusion experiment, 84% of the ethyl-FXD taken up into enterocytes was hydrolyzed. Furthermore, only one-fifth of the FXD formed in mucosa reached the mesenteric vein because of its P-glycoprotein-mediated efflux into the intestinal lumen. These findings indicate that the intestinal bioconversion of ester prodrugs to their parent drugs is a key factor in determining their oral bioavailability.
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Affiliation(s)
- Kayoko Ohura
- Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan
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72
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Croft M, Keely B, Morris I, Tann L, Lappin G. Predicting Drug Candidate Victims of Drug-Drug Interactions, using Microdosing. Clin Pharmacokinet 2012; 51:237-46. [DOI: 10.2165/11597070-000000000-00000] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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73
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Yao M, Srinivas NR. Quantification of fexofenadine in biological matrices: a review of bioanalytical methods. Biomed Chromatogr 2012; 26:942-61. [DOI: 10.1002/bmc.2712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 01/03/2012] [Indexed: 11/05/2022]
Affiliation(s)
| | - Nuggehally R. Srinivas
- Vanthys Pharmaceutical Development [P] Ltd; Phoenix Pinnacle, no. 46, 3rd Floor, Ulsoor Road; Bangalore; 560042; India
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74
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Abstract
Accelerator MS (AMS) is an ultrasensitive technique that can be used to quantify 14C in biological samples. Prior to analysis, the carbon in samples is selectively isolated, with the result that the technique is independent of compound structure and nonsusceptible to matrix effects. AMS is a tracer technique and therefore can be used to quantify all compound-related material without the need to develop extraction or chromatographic separation methods. Thus AMS has some distinct advantages over conventional assay techniques, such as LC–MS/MS. AMS also complements conventional techniques, facilitating innovative, cost-effective clinical study designs. Thus, metabolism data can be obtained from early clinical trials, identifying any human metabolites that may raise safety concerns. By administration of an intravenous 14C microtracer dose concomitantly with an extravascular dose of nonradiolabeled compound, AMS can also be used to determine absolute bioavailability and intravenous pharmacokinetic parameters without the need for intravenous toxicology or formulation development.
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75
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Harrison A, Gardner I, Hay T, Dickins M, Beaumont K, Phipps A, Purkins L, Allan G, Christian R, Duckworth J, Gurrell I, Kempshall S, Savage M, Seymour M, Simpson M, Taylor L, Turnpenny P. Case studies addressing human pharmacokinetic uncertainty using a combination of pharmacokinetic simulation and alternative first in human paradigms. Xenobiotica 2011; 42:57-74. [PMID: 21992032 DOI: 10.3109/00498254.2011.622418] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PF-184298 ((S)-2,3-dichloro-N-isobutyl-N-pyrrolidin-3-ylbenzamide) and PF-4776548 ((3-(4-fluoro-2-methoxy-benzyl)-7-hydroxy-8,9-dihydro-3H,7H-pyrrolo[2,3-c][1,7]naphthyridin-6-one)) are novel compounds which were selected to progress to human studies. Discordant human pharmacokinetic predictions arose from pre-clinical in vivo studies in rat and dog, and from human in vitro studies, resulting in a clearance prediction range of 3 to >20 mL min⁻¹ kg⁻¹ for PF-184298, and 5 to >20 mL min⁻¹ kg⁻¹ for PF-4776548. A package of work to investigate the discordance for PF-184298 is described. Although ultimately complementary to the human pharmacokinetic data in characterising the disposition of PF-184298 in humans, these data did not provide any further confidence in pharmacokinetic prediction. A fit for purpose human pharmacokinetic study was conducted for each compound, with an oral pharmacologically active dose for PF-184298, and an intravenous and oral microdose for PF-4776548. This provided a relatively low cost, clear decision making approach, resulting in the termination of PF-4776548 and further progression of PF-184298. A retrospective analysis of the data showed that, if the tools had been available at the time, the pharmacokinetics of PF-184298 in human could have been predicted from a population based simulation tool in combination with physicochemical properties and in vitro human intrinsic clearance.
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Affiliation(s)
- Anthony Harrison
- Department of Pharmacokinetics, Dynamics and Metabolism, Pfizer Worldwide Research and Development, Sandwich Laboratories, Sandwich, Kent, UK.
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76
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Prediction of Nonlinear Intestinal Absorption of CYP3A4 and P-Glycoprotein Substrates from their In Vitro Km Values. Pharm Res 2011; 29:651-68. [DOI: 10.1007/s11095-011-0579-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 08/26/2011] [Indexed: 02/05/2023]
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77
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Velický M, Tam KY, Dryfe RAW. In situ artificial membrane permeation assay under hydrodynamic control: correlation between drug in vitro permeability and fraction absorbed in humans. Eur J Pharm Sci 2011; 44:299-309. [PMID: 21864679 DOI: 10.1016/j.ejps.2011.08.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Revised: 07/28/2011] [Accepted: 08/10/2011] [Indexed: 10/17/2022]
Abstract
The purpose of this study was to develop an in vitro permeation model that will predict the fraction of drugs absorbed in humans. A rotating-diffusion cell with two aqueous compartments, separated by a lipid-impregnated artificial membrane, was used to determine the permeability of drugs under conditions of controlled hydrodynamics. The measured effective permeability coefficient was modified to include the paracellular transport derived from a previously reported colorectal adenocarcinoma epithelial cell line (Caco-2) permeability study and the effects of unstirred water layer anticipated in vivo. Permeability data were collected for 31 different marketed drugs with known absolute oral bioavailability and human hepatic clearance data. Literature bioavailability values were corrected for the first pass hepatic clearance thus obtaining the fraction absorbed from intestinal lumen (fraction absorbed), F(a), while assuming that the fraction escaping intestinal extraction, F(g), was approximately ~1. Permeability obtained under conditions of controlled hydrodynamics was compared with the permeability measured under unstirred conditions. It is shown that the optimized effective permeability correlates with the fraction absorbed. In contrast, permeability data obtained under unstirred conditions does not show a good correlation. The in vitro permeation model developed in this study predicts the fraction absorbed of the selected drugs in humans within experimental uncertainty. It has been demonstrated that the correlation with the fraction absorbed is greatly improved using the permeability data obtained under controlled hydrodynamics with paracellular transport included in the model.
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Affiliation(s)
- Matěj Velický
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
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78
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Gundogdu E, Alvarez IG, Karasulu E. Improvement of effect of water-in-oil microemulsion as an oral delivery system for fexofenadine: in vitro and in vivo studies. Int J Nanomedicine 2011; 6:1631-40. [PMID: 21904453 PMCID: PMC3160949 DOI: 10.2147/ijn.s22673] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Fexofenadine (FEX) has high solubility and low permeability (BCS, Class III). In this work, novel FEX loaded water in oil microemulsion (w/o) was designed to improve bioavailability and compared with Fexofen(®) syrup in in vitro and in vivo studies. In addition, pharmacokinetic parameters in permeability studies were estimated by using WinNonLin software program. w/o microemulsion system was optimized using a pseudoternary phase diagram, composed of span 80/lutrol F 68 (9.5:0.5 w/w), oleic acide, isopropyl alcohol and water as surfactant mixture; oil and cosurfactant was developed for oral drug delivery. w/o microemulsion systems were characterized by phase behavior, particle size, viscosity and solubilization capacity. In vitro studies were studied using Caco-2 cell monolayer. Pharmacokinetic parameters of w/o microemulsion were investigated in rabbits and compared to Fexofen(®) syrup. Fexofen(®) syrup and microemulsion were administered by oral gavage at 6 mg/kg of the same concentration. The experimental results indicated that microemulsion (HLB = 5.53) formed nanometer sized droplets (33.29 ± 1.76) and had good physical stability. This microemulsion increased the oral bioavailability of FEX which was highly water-soluble but fairly impermeable. The relative bioavailability of FEX microemulsion was about 376.76% compared with commercial syrup in rabbits. In vitro experiments were further employed for the enhanced effect of the microemulsion for FEX. These results suggest that novel w/o microemulsion plays an important role in enhancing oral bioavailability of low permeability drugs.
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Affiliation(s)
- E Gundogdu
- Faculty of Pharmacy, Department of Biopharmaceutics and Pharmacokinetics, Ege University, Izmir, Turkey.
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79
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Pharmacokinetic and pharmacogenomic profiles of telmisartan after the oral microdose and therapeutic dose. Pharmacogenet Genomics 2011; 21:495-505. [DOI: 10.1097/fpc.0b013e3283489ce2] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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80
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An AMS method to determine analyte recovery from pharmacokinetic studies with concomitant extravascular and intravenous administration. Bioanalysis 2011; 3:407-10. [PMID: 21338260 DOI: 10.4155/bio.11.6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The absolute bioavailability, clearance and volume of distribution of a drug can be investigated by administering a very low dose of the (14)C-drug intravenously along with a therapeutic nonlabeled dose by the extravascular route (typically orally). The total drug concentration is measured by an assay such as LC-MS and the (14)C-drug is measured by accelerator MS (AMS). In another article in this issue, a method validation is proposed where AMS was used as the analytical assay. Part of the validation is to assess the recovery of the analyte being measured as this has a direct impact on its quantification. In this article, a method of internal standardisation is described where the UV response of the nonlabeled analyte, spiked in excess into the matrix being analysed, is used for internal standardization. The method allows for the recovery of analyte to be measured in each individual sample being analysed. It is important to know the recovery of a (14)C-labeled analyte when determining its mass concentration from (14)C:(12)C isotopic ratio data using AMS. A method is reported in this article that utilizes the UV response of the nonlabeled drug for internal standardization, so that the recovery for each individual sample analyzed can be ascertained.
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81
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Dueker SR, Vuong LT, Lohstroh PN, Giacomo JA, Vogel JS. Quantifying exploratory low dose compounds in humans with AMS. Adv Drug Deliv Rev 2011; 63:518-31. [PMID: 21047543 PMCID: PMC3062634 DOI: 10.1016/j.addr.2010.10.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Revised: 10/08/2010] [Accepted: 10/18/2010] [Indexed: 11/20/2022]
Abstract
Accelerator Mass Spectrometry is an established technology whose essentiality extends beyond simply a better detector for radiolabeled molecules. Attomole sensitivity reduces radioisotope exposures in clinical subjects to the point that no population need be excluded from clinical study. Insights in human physiochemistry are enabled by the quantitative recovery of simplified AMS processes that provide biological concentrations of all labeled metabolites and total compound related material at non-saturating levels. In this paper, we review some of the exploratory applications of AMS (14)C in toxicological, nutritional, and pharmacological research. This body of research addresses the human physiochemistry of important compounds in their own right, but also serves as examples of the analytical methods and clinical practices that are available for studying low dose physiochemistry of candidate therapeutic compounds, helping to broaden the knowledge base of AMS application in pharmaceutical research.
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82
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Lappin G, Shishikura Y, Jochemsen R, Weaver RJ, Gesson C, Brian Houston J, Oosterhuis B, Bjerrum OJ, Grynkiewicz G, Alder J, Rowland M, Garner C. Comparative pharmacokinetics between a microdose and therapeutic dose for clarithromycin, sumatriptan, propafenone, paracetamol (acetaminophen), and phenobarbital in human volunteers. Eur J Pharm Sci 2011; 43:141-50. [DOI: 10.1016/j.ejps.2011.04.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 02/24/2011] [Accepted: 04/12/2011] [Indexed: 11/17/2022]
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83
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AMS method validation for quantitation in pharmacokinetic studies with concomitant extravascular and intravenous administration. Bioanalysis 2011; 3:393-405. [DOI: 10.4155/bio.11.5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A technique has emerged in the past few years that has enabled a drug’s intravenous pharmacokinetics to be readily obtained in humans without having to conduct extensive toxicology studies by this route of administration or expend protracted effort in formulation. The technique involves the intravenous administration of a low dose of 14C-labelled drug (termed a tracer dose) concomitantly with a non-labelled extravascular dose given at therapeutically levels. Plasma samples collected over time are analysed to determine the total parent drug concentration by LC–MS (which essentially measures that arising from the oral dose) and by LC followed by accelerator mass spectrometry (AMS) to determine the 14C-drug concentration (i.e., that arising from the intravenous dose). There are currently no published accounts of how the principles of bioanalytical validation might be applied to intravenous studies using AMS as an analytical technique. The authors describe the primary elements of AMS when used with LC seperation and how this off-line technique differs from LC–MS. They then discuss how the principles of bioanalytical validation might be applied to determine selectivity, accuracy, precision and stability of methods involving LC followed by AMS analysis.
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84
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Roberts MS. Drug structure-transport relationships. J Pharmacokinet Pharmacodyn 2010; 37:541-73. [PMID: 21107662 PMCID: PMC3005109 DOI: 10.1007/s10928-010-9174-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Accepted: 10/22/2010] [Indexed: 11/29/2022]
Abstract
Malcolm Rowland has greatly facilitated an understanding of drug structure–pharmacokinetic relationships using a physiological perspective. His view points, covering a wide range of activities, have impacted on my own work and on my appreciation and understanding of our science. This overview summarises some of our parallel activities, beginning with Malcolm’s work on the pH control of amphetamine excretion, his work on the disposition of aspirin and on the application of clearance concepts in describing the disposition of lidocaine. Malcolm also spent a considerable amount of time developing principles that define solute structure and transport/pharmacokinetic relationships using in situ organ studies, which he then extended to involve the whole body. Together, we developed a physiological approach to studying hepatic clearance, introducing the convection–dispersion model in which there was a spread in blood transit times through the liver accompanied by permeation into hepatocytes and removal by metabolism or excretion into the bile. With a range of colleagues, we then further developed the model and applied it to various organs in the body. One of Malcolm’s special interests was in being able to apply this knowledge, together with an understanding of physiological differences in scaling up pharmacokinetics from animals to man. The description of his many other activities, such as the development of clearance concepts, application of pharmacokinetics to the clinical situation and using pharmacokinetics to develop new compounds and delivery systems, has been left to others.
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Affiliation(s)
- Michael S Roberts
- School of Pharmacy and Medical Science and Sansom Institute for Health Research, University of South Australia, Adelaide, Australia.
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85
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Sugano K, Kansy M, Artursson P, Avdeef A, Bendels S, Di L, Ecker GF, Faller B, Fischer H, Gerebtzoff G, Lennernaes H, Senner F. Coexistence of passive and carrier-mediated processes in drug transport. Nat Rev Drug Discov 2010; 9:597-614. [PMID: 20671764 DOI: 10.1038/nrd3187] [Citation(s) in RCA: 435] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The permeability of biological membranes is one of the most important determinants of the pharmacokinetic processes of a drug. Although it is often accepted that many drug substances are transported across biological membranes by passive transcellular diffusion, a recent hypothesis speculated that carrier-mediated mechanisms might account for the majority of membrane drug transport processes in biological systems. Based on evidence of the physicochemical characteristics and of in vitro and in vivo findings for marketed drugs, as well as results from real-life discovery and development projects, we present the view that both passive transcellular processes and carrier-mediated processes coexist and contribute to drug transport activities across biological membranes.
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Affiliation(s)
- Kiyohiko Sugano
- Pfizer, Research Formulation, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, UK.
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