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Wang Z, Gao Y, Ji X, Wu T, Pu L, Qiu W. Effects of CYP2D6 *10 and *41 Variants in Healthy Chinese Men on the Pharmacokinetics of Dapoxetine. J Clin Pharmacol 2024; 64:601-608. [PMID: 38059315 DOI: 10.1002/jcph.2391] [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: 09/28/2023] [Accepted: 12/04/2023] [Indexed: 12/08/2023]
Abstract
Dapoxetine is a selective serotonin reuptake inhibitor (SSRI) used to treat premature ejaculation (PE), and is mainly metabolized by CYP2D6, CYP3A4, and flavin-containing monooxygenase 1. The purpose of the study was to evaluate the effect of CYP2D6 polymorphism on the pharmacokinetics of dapoxetine in healthy Chinese men. Thirty-nine subjects who received a single oral dose of 30 mg dapoxetine hydrochloride were classified based on their CYP2D6 genotype: *1/*1 (n = 9), *1/*41 (n = 1), *1/*10 (n = 12), *10/*41 (n = 3), or *10/*10 (n = 14). The difference in pharmacokinetic parameters between different genotype groups was analyzed and then scored according to the activity score system. Compared with the wild-type subjects of CYP2D6 *1/*1, the peak plasma concentration (Cmax) and the area under the plasma drug concentration-time curve (AUCinf) of dapoxetine in the *10/*10 and *10/*41 groups were notably increased (P ≤ .05). Significant differences in Cmax, AUC, volume of distribution/bioavailability (V/F) and clearance/bioavailability (CL/F) were observed among dapoxetine activity score groups (P ≤ .05). The AUCinf was increased significantly (154% and 89.73%, P ≤ .05) and the Cmax was increased significantly (73.45% and 42.67%, P ≤ .05) in CYP2D6 *10/*41 subjects, compared with CYP2D6 *1/*1 and *1/*10 subjects. The results obtained indicated that CYP2D6 *10 and *41 polymorphisms have significant effects on the pharmacokinetic properties of dapoxetine.
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Affiliation(s)
- Zhipeng Wang
- School of Pharmacy Lanzhou University, Lanzhou, Gansu, China
| | - Yuan Gao
- School of Pharmacy Lanzhou University, Lanzhou, Gansu, China
| | - Xingfang Ji
- School of Pharmacy Lanzhou University, Lanzhou, Gansu, China
| | - Tong Wu
- School of Pharmacy Lanzhou University, Lanzhou, Gansu, China
| | - Libin Pu
- School of Pharmacy Lanzhou University, Lanzhou, Gansu, China
| | - Wen Qiu
- National Drug Clinical Trial Institution, Lanzhou University Second Hospital, Lanzhou, Gansu, China
- Pharmacy Department, Lanzhou University Second Hospital, Lanzhou, Gansu, China
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Maciaszek J, Pawłowski T, Hadryś T, Machowska M, Wiela-Hojeńska A, Misiak B. The Impact of the CYP2D6 and CYP1A2 Gene Polymorphisms on Response to Duloxetine in Patients with Major Depression. Int J Mol Sci 2023; 24:13459. [PMID: 37686266 PMCID: PMC10487921 DOI: 10.3390/ijms241713459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 08/25/2023] [Accepted: 08/29/2023] [Indexed: 09/10/2023] Open
Abstract
Depression is a global mental health concern, and personalized treatment approaches are needed to optimize its management. This study aimed to investigate the influence of the CYP2D6 and CYP1A2 gene polymorphisms on the efficacy of duloxetine in reducing depressive and anxiety symptoms. A sample of 100 outpatients with major depression, who initiated monotherapy with duloxetine, were followed up. Polymorphisms in the CYP2D6 and CYP1A2 genes were assessed. The severity of depressive and anxiety symptoms was recorded using standardized scales. Adverse drug reactions (ADRs) were analyzed. Statistical analyses, including linear regression, were conducted to examine the relationships between genetic polymorphisms, clinical variables, and treatment outcomes. Patients with higher values of the duloxetine metabolic index (DMI) for CYP2D6, indicating a faster metabolism, achieved a greater reduction in anxiety symptoms. The occurrence of ADRs was associated with a lower reduction in anxiety symptoms. However, no significant associations were found between studied gene polymorphisms and reduction in depressive symptoms. No significant effects of the DMI for CYP1A2 were found. Patients with a slower metabolism may experience less benefit from duloxetine therapy in terms of anxiety symptom reduction. Personalizing treatment based on the CYP2D6 and CYP1A2 gene polymorphisms can enhance the effectiveness of antidepressant therapy and improve patient outcomes.
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Affiliation(s)
- Julian Maciaszek
- Department of Psychiatry, Wroclaw Medical University, 50-367 Wroclaw, Poland; (T.P.); (T.H.); (B.M.)
| | - Tomasz Pawłowski
- Department of Psychiatry, Wroclaw Medical University, 50-367 Wroclaw, Poland; (T.P.); (T.H.); (B.M.)
| | - Tomasz Hadryś
- Department of Psychiatry, Wroclaw Medical University, 50-367 Wroclaw, Poland; (T.P.); (T.H.); (B.M.)
| | - Marta Machowska
- Department of Clinical Pharmacology, Wroclaw Medical University, 50-367 Wroclaw, Poland; (M.M.); (A.W.-H.)
| | - Anna Wiela-Hojeńska
- Department of Clinical Pharmacology, Wroclaw Medical University, 50-367 Wroclaw, Poland; (M.M.); (A.W.-H.)
| | - Błażej Misiak
- Department of Psychiatry, Wroclaw Medical University, 50-367 Wroclaw, Poland; (T.P.); (T.H.); (B.M.)
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Cheng W, Lam RPK, Chan CK. Factors associated with seizure in tramadol overdose: a 12-year retrospective study in Hong Kong. Clin Toxicol (Phila) 2022; 60:1220-1226. [DOI: 10.1080/15563650.2022.2124919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Wendy Cheng
- Accident & Emergency Department, Queen Elizabeth Hospital, Hospital Authority, Hong Kong, S.A.R, China
| | - Rex Pui Kin Lam
- Department of Emergency Medicine, School of Clinical Medicine, The University of Hong Kong, Hong Kong, S.A.R, China
| | - Chi Keung Chan
- Hong Kong Poison Information Centre, Hospital Authority, Hong Kong, S.A.R, China
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Chan SW, Chu TTW, Ho CS, Kong APS, Tomlinson B, Zeng W. Influence of CYP2D6 and CYP3A5 Polymorphisms on the Pharmacokinetics and Pharmacodynamics of Bisoprolol in Hypertensive Chinese Patients. Front Med (Lausanne) 2021; 8:683498. [PMID: 34568359 PMCID: PMC8458697 DOI: 10.3389/fmed.2021.683498] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Accepted: 08/16/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose: This study was performed to investigate the effects of common polymorphisms in CYP2D6 and CYP3A5 on the plasma concentrations and antihypertensive effects of bisoprolol in hypertensive Chinese patients. Methods: One hundred patients with essential hypertension were treated with open-label bisoprolol 2.5 mg daily for 6 weeks. Clinic blood pressure (BP) and ambulatory BP (ABP) were measured after the placebo run-in and after 6 weeks treatment. Peak plasma concentrations of bisoprolol were measured at 3 h after the first dose and 3 h after the dose after 6 weeks treatment. Trough levels were measured before the dose after 6 weeks treatment. Bisoprolol plasma concentrations were measured with a validated liquid chromatography tandem mass spectrometry method. Six common polymorphisms in CYP2D6 and the CYP3A5 * 3 polymorphism were genotyped by TaqMan® assay. Results: After 6 weeks of treatment, clinic BP and heart rate were significantly reduced by 14.3 ± 10.9/8.4 ± 6.2 mmHg (P < 0.01) and 6.3 ± 7.6 BPM (P < 0.01), respectively. Similar reductions were seen in ABP values. Bisoprolol plasma concentration at 3 h after the first dose and 3 h post-dose after 6 weeks of treatment were significantly associated with baseline body weight (P < 0.001) but there was no significant effect of the CYP2D6 and CYP3A5 polymorphisms on these or the trough plasma concentrations. There was no significant association of the CYP2D6 and CYP3A5 polymorphisms or plasma bisoprolol concentrations with the clinic BP or ABP responses to bisoprolol. Conclusion: Bisoprolol 2.5 mg daily effectively reduced BP and HR. The common polymorphisms in CYP2D6 that were examined and the CYP3A5 * 3 polymorphism appear to have no benefit in predicting the hemodynamic response to bisoprolol in these patients.
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Affiliation(s)
- Sze Wa Chan
- School of Health Sciences, Caritas Institute of Higher Education, Hong Kong, China
| | - Tanya T W Chu
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, China
| | - Chung Shun Ho
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, China
| | - Alice P S Kong
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, China
| | - Brian Tomlinson
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, China.,Faculty of Medicine, Macau University of Science and Technology, Macau, China
| | - Weiwei Zeng
- Shenzhen Baoan Women's and Children's Hospital, Jinan University, Shenzhen, China
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Wang T, Zhou Y, Cao G. Pharmacogenetics of tamoxifen therapy in Asian populations: from genetic polymorphism to clinical outcomes. Eur J Clin Pharmacol 2021; 77:1095-1111. [PMID: 33515076 DOI: 10.1007/s00228-021-03088-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 01/11/2021] [Indexed: 12/15/2022]
Abstract
BACKGROUND Compared with western countries, Asian breast cancer patients have unique pathological and biological characteristics. Most of them are premenopausal women with HR positive. Tamoxifen as the first-line drug for premenopausal women with HR+ is involved in multiple enzymes and transporters during metabolizing and transporting process. Variants that cause decreased or inactive gene products leading to abnormal responses in tamoxifen therapy have well been studied in western countries, whereas such information is much less reported in Asian populations. OBJECTIVE In order to elucidate the relationship between genetic variants and tamoxifen-induced individual drug reactions in different Asian populations and further identify genotypes/phenotypes with potential therapeutic significance. METHODS We reviewed the frequencies of genetic variants in major enzymes and transporter genes involved in the metabolism and transport of tamoxifen across Asian populations as well as significant correlations between genotypes/metabolic phenotypes and metabolites concentrations or BC clinical outcomes. RESULTS Significant inter-ethnic differences in allele frequencies was found among Asian populations, such as CYP2D6*4, *10, *41, CYP2C9*2, ABCB1 C3435T and SLCO1B1*5, and CYP2D6*10/*10 is the most common genotype correlated with adverse clinical outcomes. Moreover, we summarized the barriers and controversies of implementing pharmacogenetics in tamoxifen therapy and concluded that more population-specific pharmacogenetic studies are needed in the future. CONCLUSION This review revealed more systematic pharmacogenomics of genes involved in the metabolism and transport besides CYP2D6, are required to optimize the genotyping strategies and guide the personalized tamoxifen therapy in Asian populations.
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Affiliation(s)
- Tingyu Wang
- College of Pharmacy, Hubei University of Chinese Medicine, Wuhan, 430065, China
| | - Yitian Zhou
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Guosheng Cao
- College of Pharmacy, Hubei University of Chinese Medicine, Wuhan, 430065, China.
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Guo L, Wang S, Wan Z, Ni S, Xu B, Zhao X, Liu L. Influence of
CYP2D6*5
and
*10
polymorphism on the pharmacokinetics of nebivolol in healthy Chinese subjects. J Clin Pharm Ther 2020; 45:632-637. [PMID: 32379356 DOI: 10.1111/jcpt.13155] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 03/11/2020] [Accepted: 04/09/2020] [Indexed: 11/28/2022]
Affiliation(s)
- Lifang Guo
- Pharmacy Department Beijing Chao‐Yang Hospital Capital Medical University Beijing China
| | - Shumin Wang
- National Institute for Drug Clinical Trial Beijing Tongren Hospital Capital Medical University Beijing China
| | - Zirui Wan
- Pharmacy Department Beijing Chao‐Yang Hospital Capital Medical University Beijing China
| | - Siyang Ni
- National Institute for Drug Clinical Trial Beijing Tongren Hospital Capital Medical University Beijing China
| | - Benshan Xu
- Pharmacy Department Beijing Chao‐Yang Hospital Capital Medical University Beijing China
| | - Xiuli Zhao
- National Institute for Drug Clinical Trial Beijing Tongren Hospital Capital Medical University Beijing China
| | - Lihong Liu
- Pharmacy Department Beijing Chao‐Yang Hospital Capital Medical University Beijing China
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Manoharan A, Shewade DG, Ravindranath PA, Rajkumar RP, Ramprasad VL, Adithan S, Damodaran SE. Resequencing CYP2D6 gene in Indian population: CYP2D6*41 identified as the major reduced function allele. Pharmacogenomics 2019; 20:719-729. [PMID: 31368850 DOI: 10.2217/pgs-2019-0049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Aim: The CYP2D6 gene is highly polymorphic and harbors population specific alleles that define its predominant metabolizer phenotype. This study aimed to identify polymorphisms in Indian population owing to scarcity of CYP2D6 data in this population. Materials & methods: The CYP2D6 gene was resequenced in 105 south Indians using next generation sequencing technology and haplotypes were reconstructed. Results & conclusion: Four novel missense variants have been designated as CYP2D6*110, *111, *112 and *113. The most common alleles were CYP2D6*1 (42%), *2 (32%), and *41 (12.3%) and diplotypes were CYP2D6*1/*2 (26%), *1/*1 (11%), *2/*41 (10%) and *1/*41 (7%) accounting for high incidence of extensive metabolizers in Indians.
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Affiliation(s)
- Aarthi Manoharan
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Puducherry 605006, India
| | - Deepak Gopal Shewade
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Puducherry 605006, India
| | | | - Ravi Philip Rajkumar
- Department of Psychiatry, Jawaharlal Institute of Postgraduate Medical Education & Research, Puducherry 605006, India
| | | | - Surendiran Adithan
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Puducherry 605006, India
| | - Solai Elango Damodaran
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Puducherry 605006, India
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Puaprasert K, Chu C, Saralamba N, Day NPJ, Nosten F, White NJ, Dondorp AM, Imwong M. Real time PCR detection of common CYP2D6 genetic variants and its application in a Karen population study. Malar J 2018; 17:427. [PMID: 30442143 PMCID: PMC6238304 DOI: 10.1186/s12936-018-2579-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 11/09/2018] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Plasmodium vivax malaria is characterized by relapses arising from the hypnozoite stages in the liver. The only currently registered drug for radical treatment to prevent relapse is primaquine. Primaquine, a prodrug, requires metabolism through the liver cytochrome CYP2D6 isoenzyme to its active metabolite. Mutations in the CYP2D6 gene may thus affect primaquine efficacy. A SNPs genotyping technique was developed to characterize the CYP2D6 genetic variants and tested this in the patients with Plasmodium vivax infection collected in a Karen population on the Thailand-Myanmar border, where P. vivax malaria is endemic. METHODS Direct sequencing of PCR-reamplified products (DSP) was used to uncover exonic CYP2D6 sequence variations. Subsequently, an allele-specific oligonucleotide probe real-time SNPs genotyping (ASO) assay was developed for rapid detection of the four clinically relevant CYP2D6 variants occurring in this population. These two in-house developed assays were used to genotype CYP2D6 mutations in blood samples obtained from 70 Karen adults. RESULTS Results showed a high degree of concordance between the DSP and ASO methods. Six CYP2D6 point mutations were identified within the Karen population: C100T, C1039T, G1661C, G1846A, C2850T and G4180C, at frequencies of 0.43, 0.43, 0.76, 0.02, 0.32 and 0.76, respectively. The CYP2D6*2, *4, *5, *10 and *36 allelic frequencies were 0.33, 0.02, 0.03, 0.40 and 0.01, respectively. Alleles conferring an intermediate CYP2D6 metabolizer phenotype comprised 46% of the total number of alleles. CONCLUSION The newly developed ASO assay is a reliable and rapid tool for large-scale CYP2D6 genotyping. The high frequency of the CYP2D6*10 allele in the Karen population warrants further assessment of its association with the radical curative efficacy of primaquine.
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Affiliation(s)
- Kanokpich Puaprasert
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Cindy Chu
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Naowarat Saralamba
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Nicholas P J Day
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Francois Nosten
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Nicholas J White
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Arjen M Dondorp
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Mallika Imwong
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
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9
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Chan W, Li MS, Sundaram SK, Tomlinson B, Cheung PY, Tzang CH. CYP2D6 allele frequencies, copy number variants, and tandems in the population of Hong Kong. J Clin Lab Anal 2018; 33:e22634. [PMID: 30069923 DOI: 10.1002/jcla.22634] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 07/05/2018] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND CYP2D6 plays a crucial role in drug metabolism of several drugs. It is known to be highly polymorphic with enzymatic activity ranging from poor to ultrarapid metabolic rates. While the frequencies of CYP2D6 alleles are generally known in different Asian populations, data on frequencies of the copy number variations (CNV) and tandems in CYP2D6 in which they occur are less well studied in these populations. METHODS A cohort of 800 consecutive, unrelated individuals were referred to Prenetics Limited (Prenetics) iGenes test by physicians in Hong Kong as part of their care with informed consent. These clinical samples were deidentified prior to further analysis. Genotyping and copy number determination of CYP2D6 were performed using target specific TaqMan® SNP genotyping and copy number assays. The phenotypes of CYP2D6 were predicted based on its genotypes and is dependent on the biallelic expression of alleles. RESULTS Among the Asian group (n = 735, 92%), the observed frequency of CYP2D6*36-*10 tandems was 34.1%. We also identified duplication of CYP2D6 alleles in 86 (11.7%) individuals of the study cohort. The frequency of all CYP2D6 duplicated alleles was 154 (10.5%) while only 28 (1.9%) of the duplications were of functional alleles (ie CYP2D6*1 and CYP2D6*2). CONCLUSION The present study provides a comprehensive analysis on the occurrences of CNV and tandems of the CYP2D6 gene in the Hong Kong population. The results contribute to the overall knowledge of pharmacogenomics and may accelerate the implementation of precision medicine in Asia.
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Affiliation(s)
- Wing Chan
- Prenetics Limited, Hong Kong City, Hong Kong
| | - Man S Li
- Prenetics Limited, Hong Kong City, Hong Kong
| | | | - Brian Tomlinson
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong City, Hong Kong
| | | | - Chi H Tzang
- Prenetics Limited, Hong Kong City, Hong Kong
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Ahmed S, Zhou Z, Zhou J, Chen SQ. Pharmacogenomics of Drug Metabolizing Enzymes and Transporters: Relevance to Precision Medicine. GENOMICS PROTEOMICS & BIOINFORMATICS 2016; 14:298-313. [PMID: 27729266 PMCID: PMC5093856 DOI: 10.1016/j.gpb.2016.03.008] [Citation(s) in RCA: 157] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 02/17/2016] [Accepted: 03/08/2016] [Indexed: 01/11/2023]
Abstract
The interindividual genetic variations in drug metabolizing enzymes and transporters influence the efficacy and toxicity of numerous drugs. As a fundamental element in precision medicine, pharmacogenomics, the study of responses of individuals to medication based on their genomic information, enables the evaluation of some specific genetic variants responsible for an individual’s particular drug response. In this article, we review the contributions of genetic polymorphisms to major individual variations in drug pharmacotherapy, focusing specifically on the pharmacogenomics of phase-I drug metabolizing enzymes and transporters. Substantial frequency differences in key variants of drug metabolizing enzymes and transporters, as well as their possible functional consequences, have also been discussed across geographic regions. The current effort illustrates the common presence of variability in drug responses among individuals and across all geographic regions. This information will aid health-care professionals in prescribing the most appropriate treatment aimed at achieving the best possible beneficial outcomes while avoiding unwanted effects for a particular patient.
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Affiliation(s)
- Shabbir Ahmed
- Department of Precision Medicine and Biopharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhan Zhou
- Department of Precision Medicine and Biopharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jie Zhou
- Department of Precision Medicine and Biopharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shu-Qing Chen
- Department of Precision Medicine and Biopharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China; International Center for Precision Medicine, Zhejiang California International NanoSystems Institute, Hangzhou 310058, China.
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Chang AK, Bijur PE, Lupow JB, Gallagher EJ. Comparative Analgesic Efficacy of Oxycodone/Acetaminophen vs Codeine/Acetaminophen for Short-Term Pain Management Following ED Discharge. PAIN MEDICINE 2015; 16:2397-404. [PMID: 26176973 DOI: 10.1111/pme.12830] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE To test the hypothesis that oxycodone/acetaminophen provides analgesia superior to codeine/acetaminophen following emergency department (ED) discharge. DESIGN Prospective, randomized, double-blind, trial. SETTING Adult inner city ED. SUBJECTS ED patients with acute extremity pain who were discharged home. METHODS Patients randomized to oxycodone/acetaminophen (5 mg/325 mg) or codeine/acetaminophen (30 mg/300 mg). The primary outcome, obtained via telephone one day after ED discharge, was the between-group difference in improvement in numerical rating scale (NRS) pain scores over a 2-hour period following the most recent ingestion of study drug. Secondary outcomes included proportion of patients with >50% pain reduction, side-effect profile, and patient satisfaction. RESULTS Two hundred and forty patients were enrolled. Mean baseline NRS scores were 7.9 in both groups. Mean decrease over 2 hours was 4.5 NRS units in the oxycodone/acetaminophen group vs 4.2 NRS units in the codeine/acetaminophen group, for a clinically and statistically nonsignificant difference of 0.2 NRS units (95% CI -0.4-0.9 NRS units). Similarly, 66% vs 61% achieved >50% pain relief for a nonsignificant difference of 5% (95% CI -8% to 17%). Side-effect profile and patient satisfaction were similar. CONCLUSION Our hypothesis that oxycodone/acetaminophen provides analgesia superior to codeine/acetaminophen was rejected. Although pain within each group was reduced by more than half, the between-group difference was not significant. Pending independent validation, these unexpected findings suggest that codeine/acetaminophen, a Schedule III agent, may be a clinically reasonable outpatient opioid alternative to oxycodone/acetaminophen, a more tightly restricted Schedule II agent thought to be more prone to misuse.
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Affiliation(s)
- Andrew K Chang
- Department of Emergency Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York, USA
| | - Polly E Bijur
- Department of Emergency Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York, USA
| | - Jason B Lupow
- Department of Emergency Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York, USA
| | - E John Gallagher
- Department of Emergency Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York, USA
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Tang KF, Zhao YL, Ding SS, Wu QF, Wang XY, Shi JQ, Sun F, Xing JP. Genetic polymorphisms of CYP2D6*10 and the effectiveness of combined tamoxifen citrate and testosterone undecanoate treatment in infertile men with idiopathic oligozoospermia. J Zhejiang Univ Sci B 2015; 16:191-7. [PMID: 25743120 DOI: 10.1631/jzus.b1400282] [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] [Indexed: 11/11/2022]
Abstract
Tamoxifen citrate, as the first line of treatment for infertile men with idiopathic oligozoospermia, was proposed by the World Health Organization (WHO), and testosterone undecanoate has shown benefits in semen values. Our objective was to assess the effectiveness of treatment with tamoxifen citrate and testosterone undecanoate in infertile men with idiopathic oligozoospermia, and whether the results would be affected by polymorphisms of CYP2D6*10. A total of 230 infertile men and 147 controls were included in the study. Patients were treated with tamoxifen citrate and testosterone undecanoate. Sex hormone, sperm parameters, and incidence of spontaneous pregnancy were detected. There were no significant differences between the control and patient groups with respect to CYP2D6*10 genotype frequencies (P>0.05). The follicle-stimulation hormone (FSH), luteinizing hormone (LH), and testosterone (T) levels were raised, and sperm concentration and motility were increased at 3 months and became significant at 6 months, and they were higher in the wild-type allele (C/C) than in the heterozygous variant allele (C/T) or homozygous variant allele (T/T) subgroups (P<0.05). In addition, the percentage of normal morphology was raised at 6 months, and represented the highest percentage in the C/C subgroup (P<0.05). The incidence of spontaneous pregnancy in the C/C subgroup was higher than that in the C/T or T/T subgroups (P<0.01). This study showed that the CYP2D6*10 variant genotype demonstrated worse clinical effects in infertile men with idiopathic oligozoospermia.
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Affiliation(s)
- Kai-fa Tang
- Department of Urology, Affiliated Hospital of Guiyang Medical College, Guiyang 550004, China; Department of Urology, the First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an 710061, China
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13
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LLerena A, Naranjo MEG, Rodrigues-Soares F, Penas-LLedó EM, Fariñas H, Tarazona-Santos E. Interethnic variability ofCYP2D6alleles and of predicted and measured metabolic phenotypes across world populations. Expert Opin Drug Metab Toxicol 2014; 10:1569-83. [DOI: 10.1517/17425255.2014.964204] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Zahari Z, Ismail R. Influence of Cytochrome P450, Family 2, Subfamily D, Polypeptide 6 (CYP2D6) Polymorphisms on Pain Sensitivity and Clinical Response to Weak Opioid Analgesics. Drug Metab Pharmacokinet 2014; 29:29-43. [DOI: 10.2133/dmpk.dmpk-13-rv-032] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Qian JC, Xu XM, Hu GX, Dai DP, Xu RA, Hu LM, Li FH, Zhang XH, Yang JF, Cai JP. Genetic variations of human CYP2D6 in the Chinese Han population. Pharmacogenomics 2013; 14:1731-43. [PMID: 24192122 DOI: 10.2217/pgs.13.160] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: The purpose of this study was to determine the genetic polymorphisms of the CYP2D6 gene and to elucidate the allele distribution pattern in the Chinese Han population. Materials & methods: We used PCR and bidirectional sequencing methods to analyze all nine exons of the CYP2D6 gene in 2129 unrelated, healthy Chinese Han subjects from two geographical locations in China: the northern and southern regions. Results: In total, 165 mutated sites were detected in 2129 participants, of which 67 sites were reported for the first time. Among these novel mutation sites, 22 were nonsynonymous and 12 were named as novel alleles (*87–*93, *94A, *94B and *95–*98) by the Human CYP Allele Nomenclature Committee. In addition, 29 previously reported alleles and 84 genotypes were also detected in 1954 volunteers. Functional prediction of novel variants revealed that eight variants might have a deleterious effect on CYP2D6. Linkage disequilibrium analysis and tagSNP selection were performed separately. By using these methods, distinct differences were found between the two regions. Conclusion: This study provides the most comprehensive data concerning CYP2D6 polymorphisms in the Chinese Han population to date and increases the number of known alleles; these findings may greatly contribute to the development of personalized medicine for the Chinese Han population. Original submitted 1 January 2013; Revision submitted 14 August 2013
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Affiliation(s)
- Jian-Chang Qian
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, No. 1, Dahua Road, Dongdan, Beijing 100730, PR China and Graduate School, Wenzhou Medical University, University-town, Wenzhou, Zhejiang 325035, PR China
| | - Xin-Min Xu
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, No. 1, Dahua Road, Dongdan, Beijing 100730, PR China and Department of Clinical Laboratory, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, PR China
| | - Guo-Xin Hu
- Department of Pharmacology, Wenzhou Medical University, University-town, Wenzhou, Zhejiang 325035, PR China
| | - Da-Peng Dai
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, No. 1, Dahua Road, Dongdan, Beijing 100730, PR China
| | - Ren-Ai Xu
- Graduate School, Wenzhou Medical University, University-town, Wenzhou, Zhejiang 325035, PR China and Department of Pharmacology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325035, PR China
| | - Li-Ming Hu
- Graduate School, Wenzhou Medical University, University-town, Wenzhou, Zhejiang 325035, PR China
| | - Fang-Hong Li
- Center of Healthcare, Wenzhou Medical University, University-town, Wenzhou, Zhejiang 325035, PR China
| | - Xiu-Hua Zhang
- Department of Pharmacology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325035, PR China
| | - Jie-Fu Yang
- Department of Cardiology, Beijing Hospital, Ministry of Health, No. 1, Dahua Road, Dongdan, Beijing, 100730, PR China
| | - Jian-Ping Cai
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, No. 1, Dahua Road, Dongdan, Beijing 100730, PR China
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Han KM, Chang HS, Choi IK, Ham BJ, Lee MS. CYP2D6 P34S Polymorphism and Outcomes of Escitalopram Treatment in Koreans with Major Depression. Psychiatry Investig 2013; 10:286-93. [PMID: 24302953 PMCID: PMC3843022 DOI: 10.4306/pi.2013.10.3.286] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 12/19/2012] [Accepted: 01/05/2013] [Indexed: 12/04/2022] Open
Abstract
OBJECTIVE Cytochrome P450 (CYP) enzymatic activity, which is influenced by CYP genetic polymorphism, is known to affect the inter-individual variation in the efficacy and tolerability of antidepressants in major depressive disorder (MDD). Escitalopram is metabolized by CYP2D6, and recent studies have reported a correlation between clinical outcomes and CYP2D6 genetic polymorphism. The purpose of this study was to determine the relationship between the CYP2D6 P34S polymorphism (C188T, rs1065852) and the efficacy of escitalopram treatment in Korean patients with MDD. METHODS A total of 94 patients diagnosed with MDD were recruited for the study and their symptoms were evaluated using the 21-item Hamilton Depression Rating scale (HAMD-21). The association between the CYP2D6 P34S polymorphism and the clinical outcomes (remission and response) was investigated after 1, 2, 4, 8, and 12 weeks of escitalopram treatment using multiple logistic regression analysis and χ(2) test. RESULTS The proportion of P allele carriers (PP, PS) in remission status was greater than that of S allele homozygotes (SS) after 8 and 12 weeks of escitalopram treatment. Similarly, P allele carriers exhibited a greater treatment response after 8 and 12 weeks of escitalopram treatment than S allele homozygotes. CONCLUSION Our results suggest that the P allele of the CYP2D6 P34S polymorphism is a favorable factor in escitalopram treatment for MDD, and that the CYP2D6 P34S polymorphism may be a good genetic marker for predicting escitalopram treatment outcomes.
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Affiliation(s)
- Kyu-Man Han
- Department of Psychiatry, College of Medicine, Korea University, Seoul, Republic of Korea
- Pharmacogenetic Research Center for Psychotropic Drugs, Korea University, Seoul, Republic of Korea
| | - Hun Soo Chang
- Pharmacogenetic Research Center for Psychotropic Drugs, Korea University, Seoul, Republic of Korea
| | - In-Kwang Choi
- Department of Psychiatry, College of Medicine, Korea University, Seoul, Republic of Korea
- Pharmacogenetic Research Center for Psychotropic Drugs, Korea University, Seoul, Republic of Korea
| | - Byung-Joo Ham
- Department of Psychiatry, College of Medicine, Korea University, Seoul, Republic of Korea
- Pharmacogenetic Research Center for Psychotropic Drugs, Korea University, Seoul, Republic of Korea
| | - Min-Soo Lee
- Department of Psychiatry, College of Medicine, Korea University, Seoul, Republic of Korea
- Pharmacogenetic Research Center for Psychotropic Drugs, Korea University, Seoul, Republic of Korea
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Polymorphisms and phenotypic analysis of cytochrome P450 2D6 in the Tibetan population. Gene 2013; 527:360-5. [DOI: 10.1016/j.gene.2013.03.110] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 03/20/2013] [Accepted: 03/25/2013] [Indexed: 11/22/2022]
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Chen B, Xu Y, Jiang T, Feng R, Sun J, Zhang W, Yang W, Li J, Adeniyi O, Chen H. Estimation of CYP2D6*10 genotypes on citalopram disposition in Chinese subjects by population pharmacokinetic assay. J Clin Pharm Ther 2013; 38:504-11. [PMID: 23981149 DOI: 10.1111/jcpt.12029] [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: 06/13/2011] [Accepted: 10/25/2012] [Indexed: 11/26/2022]
Abstract
WHAT IS KNOWN AND OBJECTIVE There is great interindividual variability in citalopram (CIT) pharmacokinetics. We attempted to establish a population pharmacokinetic (PPK) model of CIT in Chinese healthy subjects, to evaluate the effect of genetic polymorphism on CIT pharmacokinetics and to compare the PPK and non-compartmental (NCA) assays in the estimation of CIT bioequivalence. METHODS Blood samples of 23 healthy subjects were collected after administration of CIT; plasma concentration of CIT was analysed using LC/MS-MS. CYP2C19 and CYP2D6*10 genotypes were determined. PPK model was established by using nonlinear mixed-effect modelling (NONMEM). The model was evaluated using goodness-of-fit plots and relative error measurements. Bioequivalence of CIT was evaluated by both PPK and NCA method. RESULTS AND DISCUSSION The estimated population absorption rate constant (ka ), clearance (CL/F) and volume of distribution (Vd/F) in Chinese healthy subjects are 0.64 L/h, 12.7 L/h and 705 L, respectively. Different CYP2C19 and CYP2D6 genotypes have impacts on CIT pharmacokinetics. There is about 5.5% decrement of CL/F for each CYP2C19*2 or CYP2D6*10 allele. The 90% confidence interval of CIT bioavailability obtained from NCA and PPK model were 96.4-105.4% and 92.5-103.4%, respectively. WHAT IS NEW AND CONCLUSION The PPK of CIT is best characterized by a one-compartment disposition model with first-order absorption. CYP2C19 and CYP2D6 genotypes have impacts on the CL/F of CIT. Bioequivalence of CIT can be estimated by both NCA and PPK model.
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Affiliation(s)
- B Chen
- Department of Pharmacy, Ruijin Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
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Zhou LP, Luan H, Dong XH, Jin GJ, Man DL, Shang H. Genetic variants of CYP2D6 gene and cancer risk: a HuGE systematic review and meta-analysis. Asian Pac J Cancer Prev 2013; 13:3165-72. [PMID: 22994728 DOI: 10.7314/apjcp.2012.13.7.3165] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE Genetic polymorphisms in metabolic enzymes are associated with numerous cancers. A large number of single nucleotide polymorphisms (SNPs) in the CYP2D6 gene have been reported to associate with cancer susceptibility. However, the results are controversial. The aim of this Human Genome Epidemiology (HuGE) review and meta-analysis was to summarize the evidence for associations. METHODS Studies focusing on the relationship between CYP2D6 gene polymorphisms and susceptibility to cancer were selected from the Pubmed, Cochrane library, Embase, Web of Science, Springerlink, CNKI and CBM databases. Data were extracted by two independent reviewers and the meta-analysis was performed with Review Manager Version 5.1.6 and STATA Version 12.0 software. Odds ratios (ORs) with 95% confidence intervals (95%CIs) were calculated. RESULTS According to the inclusion criteria, forty-three studies with a total of 7,009 cancer cases and 9,646 healthy controls, were included in the meta-analysis. The results showed that there was a positive association between heterozygote (GC) of rs1135840 and cancer risk (OR=1.92, 95%CI: 1.14-3.21, P=0.01). In addition, we found that homozygote (CC) of rs1135840 might be a protective factor for cancer (OR=0.58, 95%CI: 0.34-0.97, P=0.04). Similarly, the G allele and G carrier (AG + GG) of rs16947 and heterozygote (A/del) of rs35742686 had negative associations with cancer risk (OR=0.69, 95%CI: 0.48-0.99, P=0.04; OR=0.60, 95%CI: 0.38-0.94, P=0.03; OR=0.50, 95%CI: 0.26-0.95, P=0.03; respectively). CONCLUSION This meta-analysis suggests that CYP2D6 gene polymorphisms are involved in the pathogenesis of various cancers. The heterozygote (GC) of rs1135840 in CYP2D6 gene might increase the risk while the homozygote (CC) of rs1135840, G allele and G carrier (AG + GG) of rs16947 and heterozygote (A/del) of rs35742686 might be protective factors.
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Affiliation(s)
- Li-Ping Zhou
- Department of Laboratory Medicine, the First Affiliated Hospital of China Medical University, Shenyang, China
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Johnson BM, Song IH, Adkison KK, Borland J, Fang L, Lou Y, Berrey MM, Nafziger AN, Piscitelli SC, Bertino JS. Evaluation of the Drug Interaction Potential of Aplaviroc, a Novel Human Immunodeficiency Virus Entry Inhibitor, Using a Modified Cooperstown 5 + 1 Cocktail. J Clin Pharmacol 2013; 46:577-87. [PMID: 16638741 DOI: 10.1177/0091270006287291] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Aplaviroc is a novel CCR5 antagonist, a class of compounds under investigation as viral entry inhibitors for the treatment of human immunodeficiency virus infection. A modified Cooperstown 5+1 cocktail was used to assess the drug interaction potential of aplaviroc. Fifteen healthy subjects were administered single oral doses of caffeine (CYP1A2), warfarin (CYP2C9), omeprazole (CYP2C19), dextromethorphan (CYP2D6), and midazolam (CYP3A) alone (reference treatment) and during steady-state administration of aplaviroc (400 mg every 12 hours, test treatment). Metabolite-to-parent area under the plasma concentration versus time curve (AUC) ratios (paraxanthine/caffeine and 5-hydroxyomeprazole/omeprazole), oral clearance (S-warfarin), AUC (midazolam), and metabolite-to-parent urinary excretion ratio (dextrorphan/dextromethorphan) were determined. The test-to-reference treatment ratios (geometric mean ratio and 90% confidence interval) were caffeine, 1.06 (0.97-1.17); S-warfarin, 0.93 (0.76-1.15); omeprazole, 1.07 (0.98-1.16); dextromethorphan, 1.17 (0.97-1.42); midazolam, 1.30 (1.04-1.63). No significant inhibition of CYP1A2, CYP2C9, CYP2C19, or CYP2D6 enzyme activity was observed. Mild inhibition of CYP3A isozymes should not preclude the use of concomitant CYP3A substrates in future clinical studies with aplaviroc.
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Liao HW, Tsai IL, Chen GY, Kuo CT, Wei MF, Hwang TJ, Chen WJ, Shen LJ, Kuo CH. Simultaneous detection of single nucleotide polymorphisms and copy number variations in the CYP2D6 gene by multiplex polymerase chain reaction combined with capillary electrophoresis. Anal Chim Acta 2013; 763:67-75. [DOI: 10.1016/j.aca.2012.12.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 11/28/2012] [Accepted: 12/03/2012] [Indexed: 02/03/2023]
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Fahy BN, Guo T, Ghose R. Impact of hepatic malignancy on CYP3A4 gene expression. J Surg Res 2012; 178:768-72. [PMID: 22763214 DOI: 10.1016/j.jss.2012.06.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 05/13/2012] [Accepted: 06/01/2012] [Indexed: 10/28/2022]
Abstract
BACKGROUND The aim of this study was to examine differences in a major enzyme system for hepatic metabolism of drugs, CYP3A4, by measuring RNA levels in the liver tissue of subjects with and without hepatic malignancy and with primary versus metastatic liver tumors. MATERIALS AND METHODS We identified liver specimens from a hospital-wide tissue repository of patients having liver resection for a clinical indication. Total RNA isolation, complementary DNA synthesis, and real-time quantitative polymerase chain reaction were performed according to the standards. Demographic, clinical, and laboratory data were obtained from medical records. Standard statistical analyses were performed with significance set to α=0.05. RESULTS Liver tissue from 27 subjects was available for analysis: 13 were without malignancy and 14 had either primary liver malignancies (n=7) or metastatic disease (n=7). Median age was 57 y, and half of the subjects were men. More than 80% of subjects were overweight or obese without differentiation between benign or malignant tumors. Fewer than 20% of subjects had diabetes or hypercholesterolemia. No preresection laboratory differences were noted between the groups (benign versus malignant or primary versus metastatic disease). Subjects with malignant liver tumors had significantly lower relative-fold CYP3A4 RNA content than those with benign liver tumors (P=0.009), but no difference in the CYP3A4 RNA content between primary and metastatic disease was seen. CONCLUSIONS This study demonstrates differences in the expression of CYP3A4 in benign and malignant human liver tumors and contributes to understanding the possible impact of malignancy on hepatic metabolism.
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Affiliation(s)
- Bridget N Fahy
- Department of Surgery, Weill Cornell Medical College, The Methodist Hospital, Houston, Texas 77030, USA.
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Impact of CYP2D6 polymorphisms on the pharmacokinetics of lovastatin in Chinese subjects. Eur J Clin Pharmacol 2012; 68:943-9. [DOI: 10.1007/s00228-011-1202-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 12/19/2011] [Indexed: 11/27/2022]
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Kurose K, Sugiyama E, Saito Y. Population differences in major functional polymorphisms of pharmacokinetics/pharmacodynamics-related genes in Eastern Asians and Europeans: implications in the clinical trials for novel drug development. Drug Metab Pharmacokinet 2011; 27:9-54. [PMID: 22123129 DOI: 10.2133/dmpk.dmpk-11-rv-111] [Citation(s) in RCA: 181] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Drug lag, recently discussed extensively in Japan, can be divided into two phases: clinical development time and application review time. The former factor is still an important problem that might be improved by promoting multi-regional clinical trials and considering the results from other similar populations with Japanese, such as Koreans and Chinese. In this review, we compare the allelic or genotype frequencies of 30 relatively common functional alleles mainly between Eastern Asians and Europeans as well as among 3 major populations in Eastern Asian countries, Japan, Korea, and China, in 12 pharmacokinetics (PK)/pharmacodynamics (PD)-related genes; CYP2C9 (*2 and *3), CYP2C19 (*2, *3 and *17), 13 CYP2D6 haplotypes including *4, *5 and *10, CYP3A5 (*3), UGT1A1 (*28 and *6), NAT2 (*5, *6 and *7), GSTM1 and GSTT1 null genotypes, SLCO1B1 521T>C, ABCG2 421C>A, and HLA-A*31:01 and HLA-B*58:01. In this review, differences in allele frequencies (AFs) or genotype frequencies (GFs) less than 0.1 (in the cases of highest AF (GF) ≥0.1) or less than 0.05 (in the cases of lowest AF (GF) <0.1) were regarded as similar. Between Eastern Asians and Europeans, AFs (or GFs) are regarded as being different for many alleles such as CYP2C9 (*2), CYP2C19 (*2, *3 and *17), CYP2D6 (*4 and *10), CYP3A5 (*3), UGT1A1 (*28 and *6), NAT2 (*5*7), GSTT1 null and ABCG2 421C>A. Among the 3 Eastern Asian populations, however, only AFs of CYP2C19*3, CYP2D6*10, HLA-A*31:01 and HLA-B*58:01 are regarded as dissimilar. For CYP2C19*3, the total functional impact on CYP2C19 could be small if the frequencies of the two null alleles CYP2C19*2 and *3 are combined. Regarding CYP2D6*10, frequency difference over 0.1 is observed only between Japanese and Chinese (0.147). Although environmental factors should be considered for PK/PD differences, we could propose that among Japan, Korea, and China, genetic differences are very small for the analyzed common PK-related gene polymorphisms. On the other hand, AFs of the two HLA alleles important for cutaneous adverse drug reactions are diverse even among Eastern Asians and thus should be taken into account.
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Affiliation(s)
- Kouichi Kurose
- Division of Medicinal Safety Science, National Institute of Health Sciences, Tokyo, Japan
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Ginsburg OM, Love RR. Breast cancer: a neglected disease for the majority of affected women worldwide. Breast J 2011; 17:289-95. [PMID: 21410589 DOI: 10.1111/j.1524-4741.2011.01067.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Recent progress with declines in mortality in some high-income countries has obscured the fact that for the majority of women worldwide who are newly diagnosed, breast cancer is a neglected disease in the context of other numerically more frequent health problems. For this growing majority, it is also an orphan disease, in that detailed knowledge about tumor characteristics and relevant host biology necessary to provide even basic care is absent. With the possible exception of nutritional recommendations, current international cancer policy and planning initiatives are irrelevant to breast cancer. The progress that has occurred in high-income countries has come at extraordinary fiscal expense and patient toxicity, which of themselves suggest nonrelevance to women and healthcare practitioners in middle- and low-income countries. The implications of these circumstances appear clear: if the promise of the now 60-year-old Declaration of Human Rights that the fruits of medical science accrue to all mankind is to be realized with respect to breast cancer, a basic and translational global research initiative should be launched.
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Affiliation(s)
- Ophira M Ginsburg
- Women's College Research Institute, Department of Medicine, University of Toronto, 790 Bay Street #708, Ontario, Canada.
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Tan PCS, Hassan SK, Mohamad NAN, Gan SH. Cytochrome P450 3A4 genetic polymorphisms and post-operative fentanyl requirements. J Clin Pharm Ther 2010; 37:100-4. [DOI: 10.1111/j.1365-2710.2010.01232.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Tsai MH, Lin KM, Hsiao MC, Shen WW, Lu ML, Tang HS, Fang CK, Wu CS, Lu SC, Liu SC, Chen CY, Liu YL. Genetic polymorphisms of cytochrome P450 enzymes influence metabolism of the antidepressant escitalopram and treatment response. Pharmacogenomics 2010; 11:537-46. [PMID: 20350136 DOI: 10.2217/pgs.09.168] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIMS The antidepressant escitalopram (S-CIT) is metabolized by the cytochrome-P450 (CYP) enzymes CYP 2D6, 2C19 and 3A4. This study evaluated the impact of CYP2D6, 2C19 and 3A4 genetic polymorphisms on plasma concentrations of S-CIT and patient treatment response. MATERIALS & METHODS A total of 100 patients diagnosed with major depressive disorder were recruited to the study and their depression symptoms were assessed using the Hamilton Depression Rating Scale. The genetic polymorphisms *4, *5 and *10 on CYP2D6, *2, *3 and *17 on CYP2C19, and *18 on CYP3A4 were selected based on their function and respective allele frequencies in Asian populations. Polymorphisms were analyzed using the SNPstream genotyping system, PCR and direct sequencing methods. The steady-state serum concentrations of S-CIT and its metabolites S-desmethylcitalopram and S-didesmethylcitalopram were analyzed by HPLC. According to semiquantitative gene dose (SGD) and gene dose (GD) models for allele combinations of these polymorphisms, CYP2D6 was clustered into intermediate (0.5, 1 and 1.5 SGD) and extensive (2 SGD) metabolizers, while CYP2C19 was clustered into poor (0 GD) and extensive (1 and 2 GDs) metabolizers. RESULTS The group of patients with intermediate CYP2D6 metabolism (0.5 SGD) had a significantly higher frequency of remitters from major depressive disorder during the 8-week treatment (p = 0.0001). Furthermore, CYP2C19 poor metabolizers had significantly higher S-CIT serum levels than did extensive metabolizers at weeks 2, 4 and 8 (p < 0.05). The allele frequencies in CYP3A4*18 and CYP2C19*17 were too low to permit further subgroup analyses. CONCLUSION Our results suggest that the genetic polymorphisms in CYP2C19 may be influencing S-CIT serum concentrations, and that specific CYP2D6 polymorphisms may be predicting patient treatment outcomes based on gene dosage analyses.
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Affiliation(s)
- Ming-Hsien Tsai
- Division of Mental Health & Addiction Medicine, Institute of Population Health Sciences, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan
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Yadav SS, Ruwali M, Pant MC, Shukla P, Singh RL, Parmar D. Interaction of drug metabolizing cytochrome P450 2D6 poor metabolizers with cytochrome P450 2C9 and 2C19 genotypes modify the susceptibility to head and neck cancer and treatment response. Mutat Res 2009; 684:49-55. [PMID: 19954746 DOI: 10.1016/j.mrfmmm.2009.11.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2009] [Revised: 11/16/2009] [Accepted: 11/24/2009] [Indexed: 11/28/2022]
Abstract
The present case-control study attempted to investigate the association of poor metabolizer (PM) genotypes of cytochrome P450 2D6 (CYP2D6*4 and CYP2D6*10) with squamous cell carcinoma of head and neck (HNSCC) and treatment response in patients receiving chemotherapy or combination of chemo- and radiotherapy. Cases with the PM genotypes of CYP2D6 displayed a significantly increased risk for HNSCC as compared to wild type genotypes. The risk was found to further increase in cases (up to 4.8) carrying combination of PM genotypes of CYP2D6, CYP2C9 (CYP2C9*2) or CYP2C19 (CYP2C19*2), suggesting that synergism amongst the PM genotypes of drug metabolizing CYPs leads to impairment in the detoxification of the tobacco carcinogens. A small increase in the risk in tobacco (chewers or smokers) or alcohol users in cases with CYP2D6*4 allele while no change or even a small decrease in risk in cases with CYP2D6*10 allele when compared to non-tobacco or alcohol users have suggested that CYP2D6 genotypes alone do not appear to interact significantly with environmental risk factors in modifying the susceptibility to HNSCC. Furthermore, most of the cases carrying PM genotypes of CYP2D6 did not respond to the treatment. Moreover, higher prevalence of non-responders among cases carrying combination of CYP2D6*4 or CYP2D6*4, CYP2C9*2 and CYP2C19*2 have demonstrated that interaction of PM genotypes may not only significantly modify the susceptibility to HNSCC but also the treatment response.
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Affiliation(s)
- Sunishtha S Yadav
- Developmental Toxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Council CSIR, P.O. Box 80, Mahatma Gandhi Marg, Lucknow 226 001, India
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Snozek CLH, O'Kane DJ, Algeciras-Schimnich A. Pharmacogenetics of solid tumors: directed therapy in breast, lung, and colorectal cancer: a paper from the 2008 william beaumont hospital symposium on molecular pathology. J Mol Diagn 2009; 11:381-9. [PMID: 19644023 DOI: 10.2353/jmoldx.2009.090003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Genetic variability in drug-metabolizing enzymes and signaling pathways affects chemotherapy-related toxicity and treatment outcome in cancer. In breast and colorectal cancer, polymorphisms in metabolic enzymes involved in tamoxifen and irinotecan therapies has led the U.S. Food and Drug Administration to address genetic factors relevant to patient consideration of treatment with these compounds. Tamoxifen therapeutic failure in breast cancer has been associated with reduced CYP2D6 activity due to inefficient activation of tamoxifen. Irinotecan toxicity in colorectal cancer is more common in patients with reduced-activity UGT1A alleles, resulting in excessive exposure to the potent SN-38 metabolite. In colorectal and lung cancers, somatic mutations in the epidermal growth factor receptor and downstream signaling molecules have been associated with the therapeutic outcome of epidermal growth factor receptor-directed therapies. This review discusses the current knowledge regarding the utility of single gene-UGT1A1, CYP2D6, EGFR, and KRAS-or multigene analysis, for optimizing breast, colorectal, and lung cancer therapy. Current advances in these areas highlight how pharmacogenetics help personalized decision-making for patient management.
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Affiliation(s)
- Christine L H Snozek
- Division of Clinical Biochemistry and Immunology, Department of Laboratory Medicine and Pathology, College of Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
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Genetic polymorphism, linkage disequilibrium, haplotype structure and novel allele analysis of CYP2C19 and CYP2D6 in Han Chinese. THE PHARMACOGENOMICS JOURNAL 2009; 9:380-94. [DOI: 10.1038/tpj.2009.31] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Li H, Feng L, Xu Y, Yao L, Ouyang T, Li J, Wang T, Fan Z, Lin B, Li J, Xie Y. The association of CYP2D6 *10 polymorphism with breast cancer risk and clinico-pathologic characteristics in Chinese women. Acta Oncol 2009; 45:597-601. [PMID: 16864175 DOI: 10.1080/02841860600660803] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
A relatively little is known of whether CYP2D6 *10 (188 C to T) polymorphism mediates susceptibility to breast cancer. In this study the CYP2D6 *10 polymorphism was detected in Chinese women (286 breast cancer patients and 305 healthy women) by a PCR-RFLP assay. We found that women with the 188T/T genotype displayed a slightly increased risk for breast cancer as compared with those with the 188C/C genotype (OR 1.36, CI 0.89-2.1), the association of the 188T/T genotype with breast cancer risk was more pronounced among postmenopausal women (OR 1.49, CI 0.8-2.76), but the association did not reach statistical significance. Furthermore, we found that patients carrying the 188T/T or T/C genotype were more likely to be a positive lymph node status than those with the 188C/C genotype (OR 2.12, CI 1.08-4.18, P = 0.019). Our results suggest that CYP2D6 *10 mutant 188T/T genotype displays a non-significant increased risk for breast cancer. Moreover, patients carrying 188T/T or T/C genotype might exhibit a more aggressive phenotype than those carrying 188C/C genotype, as the observation association of genotype with clinical outcome may be due to chance, therefore, further studies are required to confirm our present findings.
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Affiliation(s)
- Hongxia Li
- Breast Centre, Beijing Cancer Hospital, Peking University School of Oncology, Beijing, PR China
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Wang HH, Liao YW, Chiang HL, Wu JY, Chen YT. Novel DNA sequence variations of cytochrome P450 genes in the Han Chinese population. Pharmacogenomics 2009; 10:359-74. [DOI: 10.2217/14622416.10.3.359] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: Cytochrome P450 is an important monooxygenase responsible for the metabolism of a large variety of structurally diverse compounds. The aim of this study was to systematically investigate the DNA sequence variations in 14 cytochrome P450 genes relevant to drug metabolism in the Han Chinese population. Materials & methods: We sequenced these 14 genes in 23 subjects and determined the allele frequencies. Results: We identified a total of 312 genetic variants, which included 80 (25.6%) novel variants. These novel variants included 67 noncoding variants, four synonymous and nine nonsynonymous variants. Among these variants, an 11-nucleotide insertion in the 3´-flanking site of intron 6 in CYP2E1 (c.968-77_-76insGATGGGTGGAT) had the highest allele frequency of 0.565. A total of 16 of these novel variants were predicted to have potential functional consequences; however, among them only c.-1299T>A in CYP2C18 and c.-498C>A in CYP2D6 reached a frequency of 4.9%. Conclusions: This study establishes a genetic database of cytochrome P450 genes in the Han Chinese population and suggests further genetic diversity throughout this important gene family.
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Affiliation(s)
- Hui-Hung Wang
- Institute of Biomedical Sciences, Academia Sinica, No 128, Sec. 2, Academia Road, Nankang, Taipei 11529, Taiwan
| | - Yie-Wen Liao
- Institute of Biomedical Sciences, Academia Sinica, No 128, Sec. 2, Academia Road, Nankang, Taipei 11529, Taiwan
| | - Hung-Lun Chiang
- Institute of Biomedical Sciences, Academia Sinica, No 128, Sec. 2, Academia Road, Nankang, Taipei 11529, Taiwan
| | - Jer-Yuarn Wu
- Institute of Biomedical Sciences, Academia Sinica, No 128, Sec. 2, Academia Road, Nankang, Taipei 11529, Taiwan
- China Medical College Hospital, Taiwan
| | - Yuan-Tsong Chen
- Institute of Biomedical Sciences, Academia Sinica, No 128, Sec. 2, Academia Road, Nankang, Taipei 11529, Taiwan
- Duke University Medical Center, NC, USA
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Neafsey P, Ginsberg G, Hattis D, Sonawane B. Genetic polymorphism in cytochrome P450 2D6 (CYP2D6): Population distribution of CYP2D6 activity. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2009; 12:334-61. [PMID: 20183526 DOI: 10.1080/10937400903158342] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Cytochrome P-450 2D6 (CYP2D6) is involved in the metabolism of many therapeutic drugs even though the enzyme represents a small proportion of the total CYP content of human liver. In vivo phenotyping with probe drug substrates such as debrisoquine and dextromethorphan showed a clear separation between poor metabolizers (PM) and extensive metabolizers (EM). This polymorphism may affect susceptibility to environmental disease, as suggested by molecular epidemiologic studies that found an association between CYP2D6 metabolizer phenotype and cancer risk; however, this association is not consistent. There are only a few examples of CYP2D6 involvement in toxicant mechanism of action, but this has not been extensively studied. Gene probe studies documented a number of genetic polymorphisms that underlie CYP2D6 metabolizer phenotypes. The EM group carries the wild-type (*1) or active (*2) variant alleles, while the PM group carries the *3, *4, *5, or *6 alleles, all of which code for a protein that has lower or null CYP2D6 activity. The current analysis characterizes (a) influence of genotype on phenotype based upon in vivo metabolism studies of probe drugs and (b) frequency of the major genotypes in different population groups is also characterized. These data were then incorporated into Monte Carlo modeling to simulate population distributions of CYP2D6 activity. This analysis reproduced the bimodal distributions commonly seen in phenotyping studies of Caucasians and found extensive population variability in enzyme activity, as indicated by the 9- to 56-fold difference between the PM modal median and the total population median CYP2D6 activity. This substantial degree of interindividual variability in CYP function indicates that assessments involving CYP2D6 substrates need to consider the full distribution of enzyme activity in refining estimates of internal dose in health assessments of xenobiotics.
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Nurfadhlina M, Foong K, Teh LK, Tan SC, Mohd Zaki S, Ismail R. CYP2A6 polymorphisms in Malays, Chinese and Indians. Xenobiotica 2008; 36:684-92. [PMID: 16891249 DOI: 10.1080/00498250600715932] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The genetically polymorphic cytochrome P450 (CYP) 2A6 is the major nicotine-oxidase in humans that may contribute to nicotine dependence and cancer susceptibility. The authors investigated the types and frequencies of CYP2A6 alleles in the three major ethnic groups in Malaysia and CYP2A6*1A, CYP2A6*1B, CYP2A6*1x2, CYP2A6*2, CYP2A6*3, CYP2A6*4, CYP2A6*5, CYP2A6*7, CYP2A6*8 and CYP2A6*10 were determined by allele-specific polymerase chain reaction (PCR) in 270 Malays, 172 Chinese and 174 Indians. Except for CYP2A6*2 and *3 that were not detected in the Malays and Chinese, all the other alleles were detected. Frequencies for the CYP2A6*4 allele were 7, 5 and 2%, respectively, in Malays, Chinese and Indians. A statistically significant high frequency of the duplicated CYP2A6*1x2 allele occurred among Chinese. Among Malays and Chinese, the most common allele was CYP2A6*1B, but it was CYP2A6*1A among Indians. These ethnic difference in frequencies suggested that further studies are required to investigate the implications on diseases such as cancer and smoking behaviour among these major ethnic groups in Malaysia.
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Affiliation(s)
- M Nurfadhlina
- Pharmacogenetics Research Group, INFORMM, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
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Oxycodone versus codeine for triage pain in children with suspected forearm fracture: a randomized controlled trial. Pediatr Emerg Care 2008; 24:595-600. [PMID: 18772726 DOI: 10.1097/pec.0b013e3181850ca3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To compare the efficacy of pain reduction of triage oxycodone (O) versus codeine (C) to children with suspected forearm fractures. DESIGN/METHODS Children, aged 4 to 17 years, were randomized to receive O (0.2 mg/kg; maximum, 15 mg) or C (2 mg/kg; maximum, 120 mg) if isolated forearm fracture was suspected by the emergency department (ED) triage nurse. All other ED staff were blinded to the assignment. The primary outcome measure was a 5-point facial scale (0 = no pain, 4 = severe) completed by subjects to assess pain at baseline then at 30-minute intervals until ED discharge or procedural sedation for fractures requiring reduction. Ten adverse effects were assessed at baseline and the succeeding intervals. Identification of the most painful part of the visit was assessed at discharge. Efficacy and adverse effects of O versus C were compared using generalized estimate equation modeling. RESULTS One hundred seven subjects (mean age, 10.4 years; African American, 55%; males, 56%) were randomized to O (n = 51) or C (n= 56). Subjects taking O reported a pain score significantly lower than subjects taking C (0.4 faces, P = 0.01). Minor adverse effects occurred in both groups, but itching occurred less in O subjects (odds ratio, 0.37; 95% confidence interval, 0.14-0.99). The most painful part of the visit was radiography (O = 41%, C = 38%) followed by extremity examination (O = 16%, C = 13%) then casting (O = 8%, C = 13%). CONCLUSIONS Triage-administered O tended toward greater pain reduction compared with C in children with suspected forearm fractures. Although minor adverse effects occurred in both groups, itching occurred more in C. Identification of radiography as the most painful part of fracture evaluation underscores the need for early triage administration of analgesia for suspected fractures.
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CYP2D6 is a major determinant of metoprolol disposition and effects in hospitalized Russian patients treated for acute myocardial infarction. Eur J Clin Pharmacol 2008; 64:1163-73. [DOI: 10.1007/s00228-008-0525-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Accepted: 06/13/2008] [Indexed: 11/24/2022]
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Ismail R, Hussein A, Teh LK, Isa MN. CYP2D6 phenotypes among Malays in Malaysia. J Clin Pharm Ther 2008. [DOI: 10.1111/j.1365-2710.2000.00304.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Xu Y, Sun Y, Yao L, Shi L, Wu Y, Ouyang T, Li J, Wang T, Fan Z, Fan T, Lin B, He L, Li P, Xie Y. Association between CYP2D6 *10 genotype and survival of breast cancer patients receiving tamoxifen treatment. Ann Oncol 2008; 19:1423-1429. [PMID: 18407954 DOI: 10.1093/annonc/mdn155] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Human cytochrome P450 2D6 (CYP2D6) genotype may affect the efficacy of tamoxifen treatment in Caucasian women with breast cancer. The most common polymorphism of CYP2D6 in Chinese women is variant 10 (188 C to T). PATIENTS AND METHODS Tamoxifen and 4-hydroxytamoxifen (4OHtam) were measured in the serum of 37 women with breast cancer who were receiving tamoxifen treatment. The association between CYP2D6 *10 genotype and survival was determined in a cohort of 293 women with breast cancer who received tamoxifen (n = 152) or who did not (n = 141). RESULTS The serum 4OHtam concentrations were significantly lower in women with the CYP2D6 *10 homozygous variant T/T genotype than in those with the homozygous wild-type C/C genotype (P = 0.04). Among tamoxifen-treated women, women with the T/T genotype had a significantly worse disease-free survival (DFS) than those with the C/C or C/T genotype, and the T/T genotype remained an independent prognostic factor of DFS in multivariate analysis (hazard ratio = 4.7; 95% confidence interval = 1.1-20.0; P = 0.04). Among women who did not receive tamoxifen, there was no significant association between CYP2D6 *10 genotype and survival. CONCLUSION In tamoxifen-treated patients, women with the CYP2D6 *10 T/T genotype have a lower 4OHtam level in the serum and a worse clinical outcome.
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Affiliation(s)
| | - Y Sun
- Department of Traditional Chinese Medicine, Beijing Cancer Hospital & Institute, Peking University School of Oncology, Beijing, People's Republic of China
| | | | | | | | | | | | | | | | | | | | - L He
- Department of Biochemistry and Molecular Biology, Beijing Cancer Hospital & Institute, Peking University School of Oncology, Beijing, People's Republic of China
| | - P Li
- Department of Traditional Chinese Medicine, Beijing Cancer Hospital & Institute, Peking University School of Oncology, Beijing, People's Republic of China.
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Sabbagh A, Génin E, Darlu P. Selecting Predictive Markers for Pharmacogenetic Traits: Tagging vs. Data-Mining Approaches. Hum Hered 2008; 66:10-8. [DOI: 10.1159/000114161] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2006] [Accepted: 08/16/2007] [Indexed: 11/19/2022] Open
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Ozdemir V, Bertilsson L, Miura J, Carpenter E, Reist C, Harper P, Widén J, Svensson JO, Albers LJ, Kennedy JL, Endrenyi L, Kalow W. CYP2D6 genotype in relation to perphenazine concentration and pituitary pharmacodynamic tissue sensitivity in Asians: CYP2D6–serotonin–dopamine crosstalk revisited. Pharmacogenet Genomics 2007; 17:339-47. [PMID: 17429316 DOI: 10.1097/fpc.0b013e32801a3c10] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Hyperprolactinemia is a common side effect of first-generation antipsychotics mediated by antagonism of dopaminergic neurotransmission in the pituitary. Most first-generation antipsychotics are metabolized by CYP2D6 in the liver. Further, CYP2D6 is expressed in the human brain as a 5-methoxyindolethylamine O-demethylase potentially contributing to regeneration of serotonin from 5-methoxytryptamine. As dopaminergic neurotransmission is subject to regulation by serotonin, CYP2D6 may exert a nuanced (serotonergic) influence on dopaminergic tone in the pituitary. CYP2D6*10 is an allele associated with reduced enzyme function and occurs in high frequency (about 50%) in Asians. We prospectively evaluated significance of CYP2D6 genetic variation for prolactin response to perphenazine (a model first-generation antipsychotic) in Asians. METHODS A single oral dose of perphenazine (0.1 mg/kg) or placebo was administered to 22 medication-free nonsmoker healthy male Chinese-Canadian volunteers, following a double-blind within-subject randomized design. Blood samples were drawn at baseline and 2, 3, 4, 5 and 6 h after drug administration. RESULTS In volunteers with CYP2D6*10/CYP2D6*10 genotype, the mean area under curve (AUC0-6) for perphenazine concentration was 2.9-fold higher than those who carry the CYP2D6*1 allele (P<0.01). Notably, volunteers homozygous for CYP2D6*10 exhibited a significant reduction (66%) in mean pharmacodynamic tissue sensitivity as measured by the (prolactin-AUC0-6/perphenazine-AUC0-6) ratio (P=0.02). CONCLUSIONS CYP2D6 genotype is a significant contributor to perphenazine concentration in Chinese-Canadians. Importantly, prolactin response, when normalized per unit perphenazine concentration, appears to be blunted in volunteers homozygous for CYP2D6*10. We suggest that CYP2D6 genetic variation may potentially influence pharmacodynamic tissue sensitivity in the pituitary, presumably through disposition of an endogenous substrate (e.g. 5-methoxytryptamine).
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Affiliation(s)
- Vural Ozdemir
- Biomarker and Clinical Pharmacology Unit, VA Long Beach Medical Center, and School of Medicine, University of California-Irvine, 3844 East 15th Street, Long Beach, Irvine, CA 90804, USA.
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Sheng HH, Zeng AP, Zhu WX, Zhu RF, Li HM, Zhu ZD, Qin Y, Jin W, Liu Y, Du YL, Sun J, Xiao HS. Allelic distributions of CYP2D6 gene copy number variation in the Eastern Han Chinese population. Acta Pharmacol Sin 2007; 28:279-86. [PMID: 17241532 DOI: 10.1111/j.1745-7254.2007.00479.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
AIM The human cytochrome P450 2D6 (CYP2D6) gene copy number variation, involving CYP2D6 gene deletion (CYP2D6*5) and duplication or multiduplication (CYP2D6*xN), can result in reduced or increased metabolism of many clinically used drugs. The identification of CYP2D6*5 and CYP2D6*xN and the investigation of their allelic distributions in ethnic populations can be important in determining the right drug and dosage for each patient. METHODS The CYP2D6*5 and CYP2D6 genes, and CYP2D6 gene duplication were identified by 2 modified long PCR, respectively. To determine duplicated alleles, a novel long PCR was developed to amplify the entire duplicated CYP2D6 gene which was used as template for subsequent PCR amplification. A total of 363 unrelated Eastern Han Chinese individuals were analyzed for CYP2D6 gene copy number variation. RESULTS The frequency of CYP2D6*5 and CYP2D6*xN were 4.82% (n=35) and 0.69% (n=5) in the Eastern Han Chinese population, respectively. Of the 5 duplicated alleles, 3 were CYP2D6*1xN and 2 were CYP2D6*10xN. One individual was a carrier of both CYP2D6*5 and CYP2D6*1xN. Taken together, the CYP2D6 gene rearrangements were present in 10.74% of subjects. CONCLUSION Allelic distributions of the CYP2D6 gene copy number variation differ among Chinese from different regions, indicating ethnic variety in Chinese. Long PCR are convenient, cost effective, specific and semiquantitative for the detection of the CYP2D6 gene copy number variation, and amplification of the entire duplicated CYP2D6 gene is necessary for the accurate identification of duplicated alleles.
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Affiliation(s)
- Hai-hui Sheng
- National Engineering Center for Biochip at Shanghai, Shanghai 201203, China
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Cai WM, Chen B, Zhang WX. Frequency of CYP2D6*10 and *14 alleles and their influence on the metabolic activity of CYP2D6 in a healthy Chinese population. Clin Pharmacol Ther 2007; 81:95-8. [PMID: 17186005 DOI: 10.1038/sj.clpt.6100015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To study the frequency of CYP2D6(*)10 and (*)14 alleles in a healthy Chinese population, and the influence of these two alleles on the metabolic activity of CYP2D6. CYP2D6(*)10 and (*)14 genotypes of 295 healthy Chinese subjects were determined using a tetra-primer method and allele-specific amplification. CYP2D6 phenotypes of 131 subjects were determined using dextramethorphan as probe drug. There were 10 subjects with a (*)14 allele, including one homozygous for (*)14. The gene frequency of (*)10 and (*)14 alleles were 55.8 and 1.8%, respectively. The metabolic ratio (MR) of dextramethorphan in 131 subjects was 0.032+/-0.106. The MR of (*)1/(*)1, (*)1/(*)10, (*)10/(*)10, (*)1/(*)14, (*)10/(*)14, and (*)14/(*)14 groups were 0.007+/-0.012, 0.009+/-0.010, 0.042+/-0.029, 0.093, 0.11, and 1.186, respectively. The MR of subjects with (*)14 allele was higher than those of (*)1/(*)1, (*)1/(*)10, or (*)10/(*)10 groups (P<0.001). The CYP2D6(*)10 and (*)14 alleles have substantial impact on the metabolic activity of CYP2D6, and the CYP2D6(*)14 allele may be the cause of the poor metabolizer phenotype in Chinese subjects.
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Affiliation(s)
- W M Cai
- Department of Pharmacy, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, People's Republic of China.
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Rehman A, Rasool AHG, Naing L, Roshan TM, Rahman ARA. Influence of the Angiotensin II Type I Receptor Gene 1166A > C Polymorphism on BP and Aortic Pulse Wave Velocity Among Malays. Ann Hum Genet 2007; 71:86-95. [PMID: 17227479 DOI: 10.1111/j.1469-1809.2006.00304.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Angiotensin II type 1 receptor (AGT1R) gene 1166A > C polymorphism has been shown to be associated with essential hypertension and aortic stiffness as measured by carotid femoral pulse wave velocity (PWV). This study was carried out to investigate the association of the 1166A > C polymorphism with blood pressure (BP) and PWV among Malay hypertensive and normotensive subjects. Two hundred and one hypertensive subjects without evidence of cardiovascular (CV) complications and 201 age- and sex-matched normotensive subjects were studied in a cross-sectional design. Blood pressures (BP) and PWV were measured, and 1166A > C genotype was determined by polymerase chain reaction followed by restriction enzyme digestion. The 1166C allele frequency was 7.96% and 7.73% among Malay hypertensive and normotensive subjects, respectively. There was no association of the 1166A > C polymorphism with BP in the hypertensive, normotensive or overall Malay populations. PWV was significantly higher among 1166C allele carriers as compared to non-carriers (10.52 +/- 1.82 vs. 10.15 +/- 1.80, p = 0.040) in the overall population, but not in the hypertensive and normotensive populations separately. In conclusion, the frequency of 1166C polymorphism is similar among Malay hypertensive and normotensive subjects. This polymorphism has no association with BP but may have an influence on PWV in Malays, which needs further investigation.
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Affiliation(s)
- A Rehman
- School of Dental Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian Kelantan, Malaysia.
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Bernard S, Neville KA, Nguyen AT, Flockhart DA. Interethnic differences in genetic polymorphisms of CYP2D6 in the U.S. population: clinical implications. Oncologist 2006; 11:126-35. [PMID: 16476833 DOI: 10.1634/theoncologist.11-2-126] [Citation(s) in RCA: 218] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
DNA polymorphisms have been identified in the genes encoding a number of the cytochrome P450 (CYP) enzymes, leading to wide interindividual variation in drug clearance. CYP2D6 metabolizes a significant number of clinically used medications, and genetic variants of the CYP2D6 isozyme that result in varying levels of metabolic activity are of clinical importance in some settings. The exact nature of the clinical effect caused by polymorphisms of the gene depends on the drug in question and the specific variant alleles expressed, as individual variants result in differing phenotypes with a range of levels of enzymatic activity. Compromised drug efficacy due to CYP2D6 variation has been documented with a variety of agents, and this review considers a number of examples, including the 5-HT(3)-receptor antagonists, which are used in oncology supportive care for the prophylaxis of nausea and vomiting. CYP2D6 is involved in the metabolism of all of the most commonly available agents, except granisetron, and their efficacy and side effects may therefore be affected by the CYP2D6 polymorphism. Significant interethnic differences in CYP2D6 allele frequencies have been demonstrated from studies across many countries. However, incidences of polymorphisms in the U.S. population have been challenging to characterize because of the country's wide ethnic diversity. The CYP2D6 polymorphism may become more important as robust clinical tests become widely available and as the use of multiple medications and the attendant risk for drug-drug interactions increases.
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Affiliation(s)
- Stephen Bernard
- Division of Hematology and Medical Oncology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7305, USA.
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Wang WP, Ni KY, Zhou GH. Multiplex single nucleotide polymorphism genotyping by adapter ligation-mediated allele-specific amplification. Anal Biochem 2006; 355:240-8. [PMID: 16836969 DOI: 10.1016/j.ab.2006.04.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2006] [Revised: 04/04/2006] [Accepted: 04/10/2006] [Indexed: 11/21/2022]
Abstract
An improved approach for increasing the multiplex level of single nucleotide polymorphism (SNP) typing by adapter ligation-mediated allele-specific amplification (ALM-ASA) has been developed. Based on an adapter ligation, each reaction requires n allele-specific primers plus an adapter-specific primer that is common for all SNPs. Thus, only n+1 primers are used for an n-plex PCR amplification. The specificity of ALM-ASA was increased by a special design of the adapter structure and PCR suppression. Given that the genetic polymorphisms in the liver enzyme cytochrome P450 CYP2D6 (debrisoquine 4-hydroxylase) have profound effects on responses of individuals to a particular drug, we selected 17 SNPs in the CYP2D6 gene as an example for the multiplex SNP typing. Without extensive optimization, we successfully typed 17-plex SNPs in the CYP2D6 gene by ALM-ASA. The results for genotyping 70 different genome samples by the 17-plex ALM-ASA were completely consistent with those obtained by both Sanger's sequencing and PCR restriction fragment length polymorphism (PCR-RFLP) analysis. ALM-ASA is a potential method for SNP typing at an ultra-low cost because of a high multiplex level and a simple optimization step for PCR. High-throughput SNP typing could be readily realized by coupling ALM-ASA with a well-developed automation device for sample processing.
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Affiliation(s)
- Wei-peng Wang
- Huadong Research Institute for Medicine and Biotechnics, Nanjing 210002, People's Republic of China
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Lee SY, Sohn KM, Ryu JY, Yoon YR, Shin JG, Kim JW. Sequence-based CYP2D6 Genotyping in the Korean Population. Ther Drug Monit 2006; 28:382-7. [PMID: 16778723 DOI: 10.1097/01.ftd.0000211823.80854.db] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
For clinical application of pharmacogenetic tests, quantitative prediction of enzyme activity based on accurate determination of genotype is essential. There has been limited information available on the genetic polymorphism of CYP2D6 in the Korean population. In this study, CYP2D6 genotypes were assessed in 400 Korean subjects. Twenty-eight different CYP2D6 alleles and 35 genotypes were detected. On the basis of the genotype determined, the frequency of poor metabolizers and ultrarapid metabolizers were 0.22% and 1.25%, respectively. The CYP2D6 activity expected in regard to different allele combinations varies widely within the extensive and intermediate metabolizer groups. The frequencies of CYP2D6*10 and CYP2D6*5 were 45.00% and 6.13%, respectively. CYP2D6*10xN was found in 4 out of 9 cases with a CYP2D6 duplication. Fifteen heterozygotes for *41 were noted. In addition, the authors measured plasma concentrations of 16 healthy volunteers after administration of nortriptyline and identified the impact of the CYP2D6 genotype on nortriptyline metabolism. This is the first large-scale study to examine the genetic polymorphism of CYP2D6 using sequence-based genotyping in an Asian population. Our results further the understanding of CYP2D6 pharmacogenetics and could be helpful for future clinical studies in the Asian population.
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Affiliation(s)
- Soo-Youn Lee
- Department of Laboratory Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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Fu Y, Fan CH, Deng HH, Hu SH, Lv DP, Li LH, Wang JJ, Lu XQ. Association of CYP2D6 and CYP1A2 gene polymorphism with tardive dyskinesia in Chinese schizophrenic patients. Acta Pharmacol Sin 2006; 27:328-32. [PMID: 16490169 DOI: 10.1111/j.1745-7254.2006.00279.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
AIM To investigate the possible association of the CYP2D6 gene C100T polymorphism and the CYP1A2 gene C163A polymorphism with tardive dyskinesia (TD) in Chinese patients with schizophrenia. METHODS The recruited schizophrenic patients were assessed with the Abnormal Involuntary Movement Scale (AIMS), and divided into groups with TD (n=91) and without TD (n=91) according to the AIMS score. Polymorphisms of the CYP2D6 and CYP1A2 genes were determined by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP). RESULTS No allele frequencies deviated from Hardy-Weinberg equilibrium. No significant differences in genotypes frequencies of the CYP2D6 C100T polymorphism were observed between patients with TD and without TD (Chi2=4.078, P>0.05), but patients with TD had a significant excess of the T allele compared with those without TD (Chi2=4.28, P<0.05). Moreover, the frequency of the CYP1A2 C allele in patients with TD was significantly higher than that in those without TD (Chi2=6.38, P<0.05). An association between TD and the CYP2D6 100T and CYP1A2 163C alleles was observed. Additionally, there were no differences in the mean AIMS scores among different genotypes in TD patients as a group or in smokers. The results of logistic regression analysis demonstrated that mean age and duration of illness were risk factors for TD, but not sex, cumulative exposure to neuroleptic drugs in years, CYP2D6 or CYP1A2 genotype. CONCLUSION The C100T polymorphism of the CYP2D6 gene and the C163A polymorphism of the CYP1A2 gene may be associated with neuroleptic drug-induced tardive dyskinesia in Chinese patients with schizophrenia. However, genetic factors have a weaker association with susceptibility to TD compared with mean age and duration of illness.
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Affiliation(s)
- Yan Fu
- Guangzhou Psychiatry Hospital, Guangzhou 510370, China.
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49
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Sabbagh A, Darlu P. Data-Mining Methods as Useful Tools for Predicting Individual Drug Response: Application to CYP2D6 Data. Hum Hered 2006; 62:119-34. [PMID: 17057402 DOI: 10.1159/000096416] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Accepted: 08/22/2006] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Selecting a maximally informative subset of polymorphisms to predict a clinical outcome, such as drug response, requires appropriate search methods due to the increased dimensionality associated with looking at multiple genotypes. In this study, we investigated the ability of several pattern recognition methods to identify the most informative markers in the CYP2D6 gene for the prediction of CYP2D6 metabolizer status. METHODS Four data-mining tools were explored: decision trees, random forests, artificial neural networks, and the multifactor dimensionality reduction (MDR) method. Marker selection was performed separately in eight population samples of different ethnic origin to evaluate to what extent the most informative markers differ across ethnic groups. RESULTS Our results show that the number of polymorphisms required to predict CYP2D6 metabolic phenotype with a high accuracy can be dramatically reduced owing to the strong haplotype block structure observed at CYP2D6. MDR and neural networks provided nearly identical results and performed the best. CONCLUSION Data-mining methods, such as MDR and neural networks, appear as promising tools to improve the efficiency of genotyping tests in pharmacogenetics with the ultimate goal of pre-screening patients for individual therapy selection with minimum genotyping effort.
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Affiliation(s)
- Audrey Sabbagh
- Unité de Recherche en Génétique Epidémiologique et Structure des Populations Humaines, INSERM U535, Villejuif, France.
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Yin OQP, Shi XJ, Tomlinson B, Chow MSS. EFFECT OFCYP2D6*10ALLELE ON THE PHARMACOKINETICS OF LORATADINE IN CHINESE SUBJECTS. Drug Metab Dispos 2005; 33:1283-7. [PMID: 15932952 DOI: 10.1124/dmd.105.005025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Loratadine is known to be a substrate for both CYP3A4 and CYP2D6 based on a previous in vitro study. In view of the large interindividual variability in loratadine pharmacokinetics and the greater genetically determined variability of CYP2D6 activity than of CYP3A4 in vivo, we hypothesized that CYP2D6 polymorphisms may contribute to the pharmacokinetic variability of loratadine. The purpose of this study was to evaluate the effect of CYP2D6 genotype (specifically the CYP2D6*10 allele) on the pharmacokinetics of loratadine in Chinese subjects. Three groups of healthy male Chinese subjects were enrolled: group I, homozygous CYP2D6*1 (*1/*1, n=4); group II, heterozygous CYP2D6*10 (*1/*10 or *2/*10, n=6); and group III, homozygous CYP2D6*10 (*10/*10, n=7) carriers. Each subject received a single oral dose of 20 mg of loratadine under fasting conditions. Multiple blood samples were collected over 48 h, and the plasma concentrations of loratadine and its metabolite desloratadine were determined by high-performance liquid chromatography. In comparing homozygous CYP2D6*10 (group III) to heterozygous CYP2D6*10 (group II) to homozygous CYP2D6*1 (group I) subjects, loratadine oral clearance values were 7.17+/- 2.54 versus 11.06+/-1.70 versus 14.59+/-2.43 l/h/kg, respectively [one-way analysis of variance (ANOVA), p<0.01], and the corresponding metabolic ratios [area under the plasma concentration-time curve (AUC)(desloratadine)/AUC(loratadine)] were 1.55+/-0.73 versus 2.47+/- 0.46 versus 3.32+/- 0.49, respectively (one-way ANOVA, p<0.05), indicating a gene-dose effect. The results demonstrated that CYP2D6 polymorphism prevalent in the Chinese population significantly affected loratadine pharmacokinetics.
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Affiliation(s)
- Ophelia Q P Yin
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong.
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