Добавил:
kiopkiopkiop18@yandex.ru t.me/Prokururor I Вовсе не секретарь, но почту проверяю Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:
Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5195_Библиотеки_им_академика_М_И_Перельмана.pdf
Скачиваний:
0
Добавлен:
30.08.2026
Размер:
63 Мб
Скачать
B*15:02 allele and is phenytoin naïve.
263
The HLA-A*31:01 allele is found in most populations worldwide and may also be a risk factor for SJS/TEN, although it seems to be more strongly associated with other carbamazepine­induced reactions, such as DRESS and maculopapular eruptions. As such, CPIC guidelines recommend carbamazepine not be used in carbamazepine-naïve patients who are positive for HLA-B*15:02 or any HLA-A*31:01 genotype.
264
Alternative antiseizure medications other than oxcarbazepine or phenytoin (or its prodrug fosphenytoin) should be used for any HLA-B*15:02 carrier.
264
The presence of the HLA-B*58:01 allele is associated with allopurinol-induced severe cutaneous adverse reactions, and CPIC guidelines recommend carriers of the allele not receive the drug.
265
Additional HLA-B variants have been
implicated in cutaneous adverse reactions to nevirapine (HLA-B*35:05),
266,267
dapsone (HLA-B*13:01),
268,269
and methazolamide (HLA-B*59:01)
270,271
; the FDA has not issued guidelines for pharmacogenetic screening for these drugs at this time. Although most data for HLA associations with idiosyncratic drug reactions have been based on data from adults, the guidelines should be considered applicable to pediatric patients as well.
IMPROVING UPON ROUTINE THERAPEUTIC MONITORING WITH “-OMICS” DATA
The introduction of routine TDM has improved patient safety and efficacy for a number of drugs, and application of “-omics” data, such as pharmacogenomics, has the potential to lead to more precise therapy. For example, the relative activities of multiple contributing metabolic pathways, through measurement of metabolites in addition to the parent drug, are not typically captured in routine TDM. When one or more of these pathways is polymorphic, or the competing pathways have differing developmental trajectories, an understanding of the relationship between pharmacogenomics and metabolite-to-parent ratios can help in the translation of measurements taken during routine TDM into relatively more clinically meaningful numbers. Furthermore, understanding the relationship between pharmacogenomics and the contribution of individual pathways can provide insight into individual’s unique sensitivity for drug–drug interactions (DDIs). PBPK models, leveraging data on the relationship between genotype and phenotype and known trends in the ontogeny of drug-metabolizing enzymes and transporters, provides a potential means to estimate full
concentration–time course of drugs in the pediatric population. Similarly, metabolomics offers the prospect of identifying metabolomic signatures or discrete urinary biomarkers that could aid in the prediction of patient-specific pharmacokinetics and adverse event profile of a drug in a given patient.
INDIVIDUALIZED DRUG–DRUG INTERACTION RISK
Drugs are typically cleared from the body via multiple metabolic and excretory pathways that may or may not be dependent upon the effects of genetic polymorphisms. There is often a generally recognized major clearance pathway, but the specific contribution of each pathway will vary from individual to individual based on their relative expression levels for the participating enzymes. The risks of inappropriate drug exposure presented by this underlying interindividual variability can be somewhat mitigated by the practice of adjusting the dose to achieve a particular effect, such as is done with warfarin, or with the implementation of routine TDM. Nevertheless, the magnitude of change in drug exposure upon coadministration of an interacting medication will vary greatly from patient to patient, even among patients who have previously been dosed to the same systemic exposure or pharmacologic effect. When a clear genotype–phenotype relationship exists, pharmacogenomics can offer insight into an individual’s unique propensity to experience a particular DDI. Furthermore, enzyme expression within a given genotype may vary considerably as a function of age and environmental factors. Here, identification of endogenous biomarkers of activity through metabolomic screening offers an attractive avenue for determining the compliment of drug-metabolizing enzymes in a given person at a given point in time, and to predict an individualized fold­change in drug as exposure with the addition of a concomitant medication. While the use multiple concomitant medications has traditionally been associated with the adult population, the rate of polypharmacy in pediatric population has been progressively expanding. In recent years, our understanding of the interplay between pharmacogenetics and DDIs has been leveraged to quantitatively predict changes in relative drug exposure. However, refinement and clinical implementation of these predictive models, in the form of decision support tools for dose adjustment, is still outstanding. Furthermore, the incorporation of parameters reflecting the ontogeny of drug-metabolizing enzymes and transporters will be required to produce accurate estimates in the pediatric population.
PEDIATRIC PHARMACOGENETICS: CHALLENGES FOR THE FUTURE
Challenges for pediatric pharmacogenetics in the future and considerations for the design of studies to improve the quality of pharmacogenomic data in children are well exemplified by the progress in warfarin pharmacogenetics over the past 10 years. Warfarin is a 4-hydroxycoumarin anticoagulant that exerts its pharmacologic actions via the antagonism of vitamin K epoxide reductase (VKOR), the enzyme responsible for the bioactivation of vitamin K and downstream synthesis of vitamin K–dependent clotting factors II, VII, IX, and X. Warfarin is well known to be a CYP2C9 substrate, and historically, prepubertal children have been reported to require larger weight-based doses of warfarin to achieve the same target international normalized ratio (INR),
137
as older children and adults.
272
This observation is now attributed to age-
dependent changes in the ratio of liver mass to total body mass,
273
but hints that the pharmacodynamic response to warfarin may differ between younger children and adults were also present. Studies of warfarin pharmacogenetics in children have lagged behind those of adults, but the results of at least seven studies consistently have found that genetic variation in CYP2C9 and the target of warfarin action, vitamin K oxidoreductase complex 1 (VKORC1), are the most important determinants of warfarin dose in studied populations. Although these studies consistently reveal that children with VKORC1 -1639AA genotypes require significantly lower doses of warfarin to achieve the same target INR as children with -1639GG genotypes, a major inconsistency among the various studies is the relative importance of genetic (primarily VKORC1 and CYP2C9 genotype) and “nongenetic/developmental” factors as determinants of variability in the warfarin dose required to achieve a stable INR target therapeutic goal. For example, age was reported to account for 28.3% of dose variability, and genetic factors contributed approximately 4% (3.7% for VKORC1 and 0.4% for CYP2C9) in one study, whereas in six subsequent studies, the genetic contribution (predominantly VKORC1 genotype) was larger (11.9% to 52% of dose variability), but in four of these studies, the “developmental” component still exceeded the genetic contribution (reviewed in reference
274
). It has been proposed that the composition of individual study cohorts may contribute to the discrepancy between relative contributions of genetic and nongenetic factors.
274
For example, in a subgroup analysis, patients
receiving warfarin after a Fontan surgery, genetic factors accounted for approximately 50% of variability in dose and developmental factors were <10%, whereas for patients receiving warfarin for a thromboembolic disorder, developmental factors were most important, accounting for approximately 60% of variability, and genetic factors were negligible.
274
This case of pediatric warfarin pharmacogenetics provides important insights that should be considered in the design of future pharmacogenetic studies in children. First, treatment with warfarin was the primary inclusion criterion for the pediatric warfarin studies to ensure adequate cohorts for analysis. In fact, the practice of enrolling all pediatric patients based primarily on use of a specific medication, without consideration of underlying disease process is a fairly common practice in pediatrics where the numbers of affected patients generally are much smaller than adult populations. Including patients who are receiving a drug for different indications—for primary prevention of a thromboembolic event or for prophylaxis to prevent recurrent thromboembolic events, both of which may be cardiac or noncardiac in origin, and post-Fontan procedure—risks confounding the analysis when different disease mechanisms may be operative. Second, the warfarin case illustrates the importance of improved mechanistic insights into the effects of increasing age—specifically, potential differences in the influence of the processes involved in growth (e.g., changes in height, weight, and body composition) and development, such as progression through the various Tanner stages to achieve full sexual maturity— on drug disposition and response.
274
SUMMARY AND CONCLUSIONS
The postgenomic era represents an unprecedented opportunity to translate the increasing volume of untapped genomic, transcriptomic, proteomic, and metabonomic data into discoveries that favorably impact the care and treatment of children. Many diseases have their onset during childhood, and effective early intervention may have unforeseen benefits later in life. On the other hand, pharmacologic management of disease or unintended exposure to environmental toxins at critical stages of development may have consequences that are not immediately apparent due to the profound changes that occur as a fetus develops, and as newborn infants mature through childhood to adolescence and, ultimately, adulthood. Given the complexity of human development, a focus on
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
the influence of a single gene or gene product is likely to be of limited value in terms of understanding the consequences of small molecule interactions with a dynamic developmental environment. Rather, the developmental process should be perceived, at a minimum, as networks of interacting genes and different networks being operative at different developmental stages. Furthermore, the repertoire of genes operative within a given network may vary at different developmental stages, and the phenotypic manifestations of gene variants may not manifest until much later in the process of maturation. In the context of identifying new target genes or gene networks for therapeutic intervention, the most compelling challenge to pediatric pharmacogenomic research will be to identify the essential network or pathway (knowing where to look) at the appropriate developmental stage (knowing when to look). There is reason to be optimistic that new strategies and technologies will help unravel the complexities of pediatric disorders since this new knowledge is essential for children to benefit as much as adults from new treatment modalities.
REFERENCES
Lander ES, Linton LM, Birren B, et al. Initial sequencing and analysis of the human genome. Nature 2001;409:860–921.
Schwenk JM, Omenn GS. The human plasma proteome draft of 2017: building on the human plasma peptide atlas from mass spectrometry and complementary assays. J Proteome Res 2017;16:4299–4310.
Guo SW, Reed DR. The genetics of phenylthiocarbamide perception. Ann Hum Biol 2001;28:111–142. Motulsky AG. Drug reactions, enzymes, and biochemical genetics. J Am Med Assoc 1957;165:835–
837. Kalow W. Pharmacogenetics: heredity and the response to drugs. Philadelphia, PA: W.B.
Saunders, 1962. Vesell ES. Twin studies in pharmacogenetics. Hum Genet 1978;1:19–30. Mahgoub A, Idle JR, Dring LG, et al. Polymorphic hydroxylation of debrisoquine in man. Lancet
1977;2:584–586. Eichelbaum M, Spannbrucker N, Steincke B, et al. Defective N-oxidation of sparteine in man: a new
pharmacogenetic defect. Eur J Clin Pharmacol 1979;16:183–187. Küpfer A, Preisig R. Pharmacogenetics of mephenytoin: a new drug hydroxylation polymorphism in
man. Eur J Clin Pharmacol 1984;26:753–759. Ensom MH, Davis GA, Cropp CD, et al. Clinical pharmacokinetics in the 21st century. Does the
evidence support definitive outcomes. Clin Pharmacok inet 1998;34:265–279. Weinshilboum R. Inheritance and drug response. N Engl J Med 2003;348:529–537. Johnson JA. Drug target pharmacogenomics: an overview. Am J Pharmacogenomics 2001;1:271–281. Evans WE, McLeod HL. Pharmacogenomics—drug disposition, drug targets, and side effects. N Engl
J Med 2003;348:538–549. McKusick VA, Ruddle FH. A new discipline, a new name, a new journal. Genomics 1987;1:1–2.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
Venter JC, Adams MD, Myers EW, et al. The sequence of the human genome. Science 2001;291:1304–1351.
Pennisi E. Reaching their goal early, sequencing labs celebrate. Science 2003;300:409. Velculescu VE, Zhang L, Zhou W, et al. Characterization of the yeast transcriptome. Cell 1997;88:243–
251. Velculescu VE, Madden SL, Zhang L, et al. Analysis of human transcriptomes. Nat Genet
1999;23:387–388. Kahn P. From genome to proteome: looking at a cell’s proteins. Science 1995;270:369–370. Hunter PJ, Borg TK. Integration from proteins to organs: the physiome project. Nat Rev Mol Cell Biol
2003;4:237–243. Tweedale H, Notley-McRobb L, Ferenci T. Effect of slow growth on metabolism of Escherichia coli,
as revealed by global metabolite pool (‘metabolome’) analysis. J Bacteriol 1988;180:5109–5116. Nicholson JK, Lindon JC, Holmes E. ‘Metabonomics’: understanding the metabolic responses of living
systems to pathophysiologic stimuli via multivariate analysis of biological NMR data. Xenobiotica 1999;29:1181–1189.
Clayton TA, Lindon JC, Clorec O, et al. Pharmaco-metabonomic phenotyping and personalized drug treatment. Nature 2006;440:1073–1077.
Agrafiotis DK, Lobanov VS, Salemme FR. Combinatorial informatics in the post-genomics era. Nat Rev Drug Discov 2002;1:337–346.
Yang K, Han X. Lipidomics: techniques, applications, and outcomes related to biomedical sciences. Trends Biochem Sci 2016;41:954–969.
Daly MJ, Rioux JD, Schaffner SF, et al. High-resolution haplotype structure in the human genome. Nat Genet 2001;2:229–232.
Beckmann JS, Estivill X, Antonarakis SE. Copy number variants and genetic traits: closer to the resolution of phenotypic to genotypic variability. Nat Rev Genet 2007;8:639–646.
Frazer KA, Murray SS, Schork NJ, et al. Human genetic variation and its contribution to complex traits. Nat Rev Genet 2009;10:241–251.
Meyer UA. Genotype or phenotype: the definition of a pharmacogenetic polymorphism. Pharmacogenetics 1991;1:66–67.
Leeder JS. Pharmacogenetics and pharmacogenomics. Pediatr Clin North Am 2001;48:756–781. Hines RN, McCarver DG. The ontogeny of human drug-metabolizing enzymes: phase I oxidative
enzymes. J Pharmacol Exp Ther 2002;300:355–360. McCarver DG, Hines RN. The ontogeny of human drug metabolizing enzymes: phase II conjugation
enzymes and regulatory mechanisms. J Pharmacol Exp Ther 2002;300:361–366. Nuwaysir EF, Bittner M, Trent J, et al. Microarrays and toxicology: the advent of toxicogenomics. Mol
Carcinog 1999;24:153–159. Kennedy S. The role of proteomics in toxicology: identification of biomarkers of toxicity by protein
expression analysis. Biomarkers 2002;7:269–290. Klein TE, Chang JT, Cho MK, et al. Integrating genotype and phenotype information: an overview of
the PharmGKB project. Pharmacogenomics J. 2001;1:167–170. Collins MD, Mao GE. Teratology of retinoids. Annu Rev Pharmacol Toxicol. 1999;39:399–430. Nulman I, Rovet J, Stewart DE, et al. Child development following exposure to tricyclic depressants or
fluoxetine throughout fetal life: a prospective, controlled study. Am J Psychiatry 2002;159:1889–1895. Watkins PB. Role of cytochromes P450 in drug metabolism and hepatotoxicity. Semin Liver Dis
1990;10:235–250.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
Streetman DS, Bertino JS, Nafziger AN. Phenotyping of drug-metabolizing enzymes in adults: a review of in-vivo cytochrome P450 phenotyping probes. Pharmacogenetics 2000;10:187–216.
Evans WE, Relling MV, Petros WP, et al. Dextromethorphan and caffeine as probes for simultaneous determination of debrisoquin-oxidation and N-acetylation phenotypes in children. Clin Pharmacol Ther 1989;45:568–573.
Pariente-Khayat A, Pons G, Rey E, et al. Caffeine acetylator phenotyping during maturation in infants. Pediatr Res 1991;29:492–495.
Relling MV, Cherrie J, Schell MJ, et al. Lower prevalence of the debrisoquin oxidative poor metabolizer phenotype in American black versus white subjects. Clin Pharmacol Ther 1991;50:308–313.
Bosso JA, Liu Q, Evans WE, et al. CYP2D6, N-acetylation, and xanthine oxidase activity in cystic fibrosis. Pharmacotherapy 1996;16:749–753.
Skoda RC, Gonzalez FJ, Demierre A, et al. Two mutant alleles of the human cytochrome P450dbl gene associated with genetically deficient metabolism of debrisoquine and other drugs. Proc Natl Acad Sci U S A. 1988;85:5240–5243.
Heim MH, Meyer UA. Genetic polymorphism of debrisoquine oxidation: restriction fragment analysis and allele-specific amplification of mutant alleles of CYP2D6. Methods Enzymol 1991;206:173–183.
Gaedigk A, Bradford LD, Marcucci KA, et al. Unique CYP2D6 activity distribution and genotype­phenotype discordance in black Americans. Clin Pharmacol Ther 2002;72:76–89.
Burgner D, Davila S, Breunis WB, et al. A genome-wide association study identifies novel and functionally related susceptibility loci for Kawasaki disease. PLoS Genet 2009;5:e1000319.
Moffatt MF, Kabesch M, Liang L, et al. Genetic variants regulating ORMDL3 expression contribute to the risk of childhood asthma. Nature 2007;448:470–473.
Kugathasan S, Baldassano RN, Bradfield JP, et al. Loci on 20q13 and 21q22 are associated with pediatric-onset inflammatory bowel disease. Nat Genet 2008;40:1211–1215.
Takeuchi F, McGinnis R, Bourgeois S, et al. A genome-wide association study confirms VKORC1, CYP2C9, and CYP4F2 as principal genetic determinants of warfarin dose. PLoS Genet 2009;5(3):e1000433.
Shuldiner AR, O’Connell JR, Bliden KP, et al. Association of cytochrome P450 2C19 genotype with the antiplatelet effect and clinical efficacy of clopidogrel therapy. JAMA 2009;302:849–857.
Search Collaborative Group. SLCO1B1 variants and statin-induced myopathy—a genomewide study. N Engl J Med 2008;359:789–799.
Marguerat S, Wilhelm BT, Bähler J. Next-generation sequencing: applications beyond genomes. Biochem Soc Trans 2008;36:1091–1096.
Twist GP, Gaedigk A, Miller NA, et al. Constellation: a tool for rapid, automated phenotype assignment of a highly polymorphic pharmacogene, CYP2D6, from whole genome sequences. NPJ Genom Med 2016;1:15007.
U.S. Food and Drug Administration, ed. FDA authorizes first direct-to-consumer test for detecting genetic variants that may be associated with medication metabolism. https://www.fda.gov/news­events/press-announcements/fda-authorizes-first-direct-consumer-test-detecting-genetic-variants-may­be-associated-medication
Iwamoto N, Shimada T. Recent advances in mass spectrometry-based approaches for proteomics and biologics: great contribution for developing therapeutic antibodies. Pharmacol Therapeut 2018;185:147–154.
Aebersold R, Burlingame AL, Bradshaw RA. Western blots versus selected reaction monitoring assays: time to turn the tables? Mol Cell Proteomics 2013;12:2381–2382.
Prasad B, Achour B, Artursson P, et al. Toward a consensus on applying quantitative liquid chromatography-tandem mass spectrometry proteomics in translational pharmacology research: a white
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
paper. Clin Pharmacol Ther 2019;106:525–543. Heimbach T, Lin W, Hourcade-Potelleret F, et al. Physiologically based pharmacokinetic modeling to
supplement nilotinib pharmacokinetics and confirm dose selection in pediatric patients. J Pharm Sci 2019;108:2191–2198.
Jorga K, Chavanne C, Frey N, et al. Bottom-up meets top-down: complementary physiologically based pharmacokinetic and population pharmacokinetic modeling for regulatory approval of a dosing algorithm of Valganciclovir in very young children. Clin Pharmacol Ther 2016;100:761–769.
Johnson TN, Rostami-Hodjegan A. Resurgence in the use of physiologically based pharmacokinetic models in pediatric clinical pharmacology: parallel shift in incorporating the knowledge of biological elements and increased applicability to drug development and practice. Pediatr Anesth 2011;21:291–
301. Rowland A, Ruanglertboon W, van Dyk M, et al. Plasma extracellular nanovesicle (exosome)-derived
biomarkers for drug metabolism pathways: a novel approach to characterize variability in drug exposure. Br J Clin Pharmacol 2019;85:216–226.
Li CY, Hosey-Cojocari C, Basit A, et al. Optimized renal transporter quantification by using aquaporin 1 and aquaporin 2 as anatomical markers: application in characterizing the ontogeny of renal transporters and its correlation with hepatic transporters in paired human samples. AAPS J 2019;21:88.
Kaddurah-Douk R, Kristal BS, Weinshilboum RM. Metabolomics: a global biochemical approach to drug response and disease. Annu Rev Pharmacol Toxicol 2008;48:653–683.
Tay-Sontheimer JC, Shireman L, Beyer RP, et al. Discovery of an endogenous urinary biomarker of CYP2D6 activity. Pharmacogenomics 2014;15:1947–1962.
Geiger C, Geistlinger L, Altmaier E, et al. Genetics meets metabolomics: a genome-wide association study of metabolite profiles in human serum. PLoS Genet 2008;4(11):E1000282.
Xu EY, Perlina A, Vu H, et al. Integrated pathway analysis of rat urine metabolic profiles and kidney transcriptomic profiles to elucidate the systems toxicology of model nephrotoxicants. Chem Res Toxicol 2008;21:1548–1561.
Bhattacharyya S, Ahmed AT, Arnold M, et al. Metabolomic signature of exposure and response to citalopram/escitalopram in depressed outpatients. Transl Psychiatry 2019;9:173.
Kaddurah-Daouk R, Boyle SH, Matson W, et al. Pretreatment metabotype as a predictor of response to sertraline or placebo in depressed outpatients: a proof of concept. Transl Pscychiatry 2011;1:e26.
Hines RN. The ontogeny of drug metabolism enzymes and implications for adverse drug events. Pharmacol Ther 2008;118:250–267.
Zanger UM, Turpeinen M, Klein K, et al. Functional pharmacogenetics/genomics of human cytochromes P450 involved in drug biotransformation. Anal Bioanal Chem 2008;392:1093–1108.
Zanger UM, Klein K, Saussele T, et al. Polymorphic CYP2B6: molecular mechanisms and emerging clinical significance. Pharmacogenomics 2007;8:743–759.
Daly AK, Rettie AE, Fowler DM, et al. Pharmacogenomics of CYP2C9: Functional and clinical considerations. J Pers Med 2017;8:1.
Furuta T, Sugimoto M, Shirai N, et al. CYP2C19 pharmacogenomics associated with therapy of
Helicobacter pylori infection and gastro-esophageal reflux diseases with a proton pump inhibitor. Pharmacogenomics 2007;8:1199–1210.
Zanger UM, Raimundo S, Eichelbaum M. Cytochrome P450 2D6: overview and update on pharmacology, genetics and biochemistry. Naunyn-Schmiedebergs Arch Pharmacol 2004;369:23–37.
Sistonen J, Sajantila A, Lao O, et al. CYP2D6 worldwide genetic variation shows high frequency of altered activity variants and no continental structure. Pharmacogenet Genomics 2007;17:93–101.
Nofziger C, Turner AJ, Sangkuhl K, et al. PharmVar genereview: CYP2D6. Clin Pharmacol Ther
2019. doi:10.1002/cpt.1643.
78.
79.
80.
81.
82.
83.
84.
85.
86.
87.
88.
89.
90.
91.
92.
93.
94.
95.
96.
97.
Lee S-J, Goldstein JA. Functionally defective or altered CYP3A4 and CYP3A5 single nucleotide polymorphisms and their detection with genotyping tests. Pharmacogenomics 2005;6:357–371.
Guillemette C. Pharmacogenomics of human UDP-glucuronosyltransferase enzymes. Pharmacogenomics J 2003;3:136–158.
Nagar S, Blanchard RL. Pharmacogenetics of uridine diphosphoglucuronsyltransferase (UGT) 1A family members and its role in patient response to irinotecan. Drug Metab Rev 2006;38:393–409.
Hildebrandt MA, Carrington DP, Thomae BA, et al. Genetic diversity and function in the human cytosolic sulfotransferases. Pharmacogenomics J 2007;7:133–143.
Sim E, Lack N, Wang CJ, et al. Arylamine N-acetyltransferases: structural and functional implications of polymorphisms. Toxicology 2008;254:170–183.
Wang L, Weinshilboum R. Thiopurine S-methyltransferase pharmacogenetics: insights, challenges and future directions. Oncogene 2006;25:1629–1638.
Kutt H, Wolk M, Scherman R, et al. Insufficient parahydroxylation as a cause of diphenylhydantoin toxicity. Neurology (NY) 1964;14:542–548.
Kidd RS, Curry TB, Gallagher S, et al. Identification of a null allele of CYP2C9 in an African­American exhibiting toxicity to phenytoin. Pharmacgenetics 2001;11:803–808.
Steward DJ, Haining RL, Henne KR, et al. Genetic association between sensitivity to warfarin and expression of CYP2C9*3. Pharmacogenetics 1997;7:361–367.
Sullivan-Klose TH, Ghanayem BI, Bell DA, et al. The role of the CYP2C9-Leu
359
allelic variant in the
tolbutamide polymorphism. Pharmacogenetics 1996;6:341–349. Bhasker CR, Miners JO, Coulter S, et al. Allelic and functional variability of cytochrome P4502C9.
Pharmacogenetics 1997;7:51–58. Rettie AE, Wienkers LC, Gonzalez FJ, et al. Impaired (S)-warfarin metabolism catalysed by the R144C
allelic variant of CYP2C9. Pharmacogenetics 1994;4:39–42. Haining RL, Hunter AP, Veronese ME, et al. Allelic variants of human cytochrome P4502C9:
baculovirus-mediated expression, purification, structural characterization, substrate stereospecificity and prochiral selectivity of the wild-type and I359L mutant forms. Arch Biochem Biophys 1996;333:447–
458. Dickman LJ, Rettie AE, Kneller MB, et al. Identification and functional characterization of a new
CYP2C9 variant (CYP2C9*5) expressed among African Americans. Mol Pharmacol 2001;60:382–
387. Blaisdell J, Jorge-Nebert LF, Coulter S, et al. Discovery of new potentially defective alleles of human
CYP2C9. Pharmacogenetics 2004;14:527–537. Dorado P, Lopez-Torres E, Penas-Lledo EM, et al. Neurological toxicity after phenytoin infusion in a
pediatric patient with epilepsy: influence of CYP2C9, CYP2C19 and ABCB1 genetic polymorphisms. Pharmacogenomics J 2013;13:359–361.
Silvado CE, Terra VC, Twardowschy CA. CYP2C9 polymorphisms in epilepsy: influence on phenytoin treatment. Pharmacogenomics Pers Med 2018;11:51–58.
Goldstein JA. Clinical relevance of genetic polymorphisms in the human CYP2C subfamily. Br J Clin Pharmacol 2001;52:349–355.
Furuta T, Shirai N, Takashima M, et al. Effect of genotypic differences in CYP2C19 on cure rates for Helicobacter pylori infection by triple therapy with a proton pump inhibitor, amoxicillin, and clarithromycin. Clin Pharmacol Ther 2001;69:158–168.
Sim SC, Risinger C, Dahl ML, et al. A common novel CYP2C19 gene variant causes ultrarapid drug metabolism relevant for the drug response to proton pump inhibitors and antidepressants. Clin Pharmacol Ther 2006;79:103–113.
98.
99.
100.
101.
102.
103.
104.
105.
106.
107.
108.
109.
110.
111.
112.
113.
114.
115.
116.
117.
118.
Rudberg I, Mohebi B, Hermann M, et al. Impact of the ultrarapid CYP2C19*17 allele on serum concentration of escitalopram in psychiatric patients. Clin Pharmacol Ther 2008;83(2):322–327.
Moriyama B, Obeng AO, Barbarino J, et al. Clinical pharmacogenetics implementation consortium (CPIC) guidelines for CYP2C19 and voriconazole therapy. Clin Pharmacol Ther 2017;102:45–51.
Aldrich SL, Poweleit EA, Prows CA, et al. Influence of CYP2C19 metabolizer status on escitalopram/citalopram tolerability and response in youth with anxiety and depressive disorders. Front Pharmacol 2019;10:99.
Strawn JR, Poweleit EA, Ramsey LB. CYP2C19-guided escitalopram and sertraline dosing in pediatric patients: a pharmacokinetic modeling study. J Child Adolesc Psychopharmacol 2019;29:340–347.
Hicks JK, Bishop JR, Sangkuhl K, et al. Clinical pharmacogenetics implementation consortium (CPIC) guideline for CYP2D6 and CYP2C19 genotypes and dosing of selective serotonin reuptake inhibitors. Clin Pharmacol Ther 2015;98:127–134.
Gaedigk A, Gotschall RR, Forbes NS, et al. Optimization of cytochrome P450 2D6 (CYP2D6) phenotype assignment using a genotyping algorithm based on allele frequency data. Pharmacogenetics 1999;9:669–682.
Gaedigk A, Sangkuhl K, Whirl-Carrillo M, et al. Prediction of CYP2D6 phenotype from genotype across world populations. Genet Med 2017;19:69–76.
Koren G, Cairns J, Chitayat D, et al. Pharmacogenetics of morphine poisoning in a breastfed neonate of a codeine-prescribed mother. Lancet 2007;368:704–705.
Treluyer J-M, Jacqz-Aigrain E, Alvarez F, et al. Expression of CYP2D6 in developing human liver. Eur J Biochem 1991;202:583–588.
Stevens JC, Marsh SA, Zaya MJ, et al. Developmental changes in human liver CYP2D6 expression. Drug Metab Disp 2008;36:1587–1593.
Blake MJ, Gaedigk A, Pearce RE, et al. Ontogeny of dextromethorphan O and N-demethylation in the first year of life. Clin Pharmacol Ther 2007;81:510–516.
Sallee FR, DeVane CL, Ferrell RE. Fluoxetine-related death in a child with cytochrome P-450 2D6 genetic deficiency. J Child Adol Psychopharmacol 2000;10:27–34.
Sindrup SH, Brøsen K. The pharmacogenetics of codeine hypoalgesia. Pharmacogenetics 1995;5:335–346.
Poulsen L, Arendt-Nielsen L, Brøsen K, et al. The hypoalagesic effect of tramadol in relation to CYP2D6. Clin Pharmacol Ther 1996;60:636–644.
Quiding H, Olsson GL, Boreus LO, et al. Infants and young children metabolise codeine to morphine. A study after single and repeated rectal administration. Br J Clin Pharmacol 1992;33:45–49.
Quiding H, Anderson P, Bondesson U, et al. Plasma concentrations of codeine and its metabolite, morphine, after single and repeated oral administration. Eur J Clin Pharmacol 1986;30:673–677.
Williams DG, Patel A, Howard RF. Pharmacogenetics of codeine metabolism in an urban population of children and its implications for analgesic reliability. Br J Anaesth 2002;89:839–845.
Crews KR, Gaedigk A, Dunnenberger HM, et al.; Clinical Pharmacogenetics Implementation Consortium. Clinical pharmacogenetics implementation consortium guidelines for cytochrome P450 2D6 genotype and codeine therapy: 2014 update. Clin Pharmacol Ther 2014;95:376–382.
de Leon J. Translating pharmacogenetics to clinical practice: do cytochrome P450 2D6 ultrarapid metabolizers need higher atomoxetine doses? J Am Acad Child Adolesc Psychiatry 2015;54:532–534.
Brown JT, Bishop JR, Sangkuhl K, et al. Clinical pharmacogenetics implementation consortium (CPIC) guideline for CYP2D6 genotype and atomoxetine therapy. Clin Pharmacol Ther 2019;106:94–102.
Gaedigk A, Dinh JC, Jeong H-Y, et al. Ten years’ experience with the CYP2D6 activity score: a perspective on future investigations to improve clinical predictions for precision therapeutics. J Pers Med 2018;8:15.