Population Differences in the Genetic Polymorphism of CYP2B6 May Impact on the Pharmacology of MMT

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building INTELEK Repository
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collectionurl https://intelek.unisza.edu.my/intelek/pages/search.php?search=!collection407072
date 2016-03-21 09:19:49
format Restricted Document
id 12770
institution UniSZA
originalfilename 7077-01-FH02-FP-16-05526.jpg
person norman
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resourceurl https://intelek.unisza.edu.my/intelek/pages/view.php?ref=12770
spelling 12770 https://intelek.unisza.edu.my/intelek/pages/view.php?ref=12770 https://intelek.unisza.edu.my/intelek/pages/search.php?search=!collection407072 Restricted Document Article Journal image/jpeg inches 96 96 norman 770 05 05 2016-03-21 09:19:49 1357x770 1357 7077-01-FH02-FP-16-05526.jpg UniSZA Private Access Population Differences in the Genetic Polymorphism of CYP2B6 May Impact on the Pharmacology of MMT PUBLIC HEALTH GENOMICS Objective: Introduced by the German as a synthetic opioid analgesic, methadone is used world-wide as a substitution treatment for opioid dependence. It is a chiral compound and its pharmacology is complex. This can further be complicated by population differences in the genetic polymorphisms of enzymes metabolizing the drug and preferential metabolism of specific isomers. Administered as a chiral mixture, its active S-form is preferentially metabolized by the polymorphic CYP2B6, with the CYP2B6*6 allele [SNPs 785A>G (rs2279343) and 516G>T (rs3745274)] associated with slow metabolism. Material and Methods: We genotyped a well-characterized sample of 92 opiate dependent individuals in several prisons in Malaysia and treated with MMT. Daily doses ranged from 5 to 120 mg (mean 57.5±33 mg). Results: Mean S-methadone serum concentrations corrected for dose in subjects homozygous for CYP2B6*6 (4.44±1.87 ng/ml.mg) were significantly higher than for heterozygous (2.64±1.48) and noncarriers (2.70±1.83) (P = 0.046). Similar patterns were observed for R to S-methadone ratios with CYP2B6*6/*6 having lower ratios (0.68±0.10) than heterozygous (1.02±0.39) and non-carriers (1.20±0.67) (P = 0.000). No significant difference was found with R-methadone, the metabolites (EDDP), and the total R,S-methadone serum concentrations. Conclusion: Preferential metabolism of active S-methadone is an important consideration for methadone when interpreting serum concentrations in diverse populations with different patterns of genetic polymorphism of CYP2B6 especially when it is administered as a racemate mixture. 18 KARGER KARGER 12
spellingShingle Population Differences in the Genetic Polymorphism of CYP2B6 May Impact on the Pharmacology of MMT
summary Objective: Introduced by the German as a synthetic opioid analgesic, methadone is used world-wide as a substitution treatment for opioid dependence. It is a chiral compound and its pharmacology is complex. This can further be complicated by population differences in the genetic polymorphisms of enzymes metabolizing the drug and preferential metabolism of specific isomers. Administered as a chiral mixture, its active S-form is preferentially metabolized by the polymorphic CYP2B6, with the CYP2B6*6 allele [SNPs 785A>G (rs2279343) and 516G>T (rs3745274)] associated with slow metabolism. Material and Methods: We genotyped a well-characterized sample of 92 opiate dependent individuals in several prisons in Malaysia and treated with MMT. Daily doses ranged from 5 to 120 mg (mean 57.5±33 mg). Results: Mean S-methadone serum concentrations corrected for dose in subjects homozygous for CYP2B6*6 (4.44±1.87 ng/ml.mg) were significantly higher than for heterozygous (2.64±1.48) and noncarriers (2.70±1.83) (P = 0.046). Similar patterns were observed for R to S-methadone ratios with CYP2B6*6/*6 having lower ratios (0.68±0.10) than heterozygous (1.02±0.39) and non-carriers (1.20±0.67) (P = 0.000). No significant difference was found with R-methadone, the metabolites (EDDP), and the total R,S-methadone serum concentrations. Conclusion: Preferential metabolism of active S-methadone is an important consideration for methadone when interpreting serum concentrations in diverse populations with different patterns of genetic polymorphism of CYP2B6 especially when it is administered as a racemate mixture.
title Population Differences in the Genetic Polymorphism of CYP2B6 May Impact on the Pharmacology of MMT
title_full Population Differences in the Genetic Polymorphism of CYP2B6 May Impact on the Pharmacology of MMT
title_fullStr Population Differences in the Genetic Polymorphism of CYP2B6 May Impact on the Pharmacology of MMT
title_full_unstemmed Population Differences in the Genetic Polymorphism of CYP2B6 May Impact on the Pharmacology of MMT
title_short Population Differences in the Genetic Polymorphism of CYP2B6 May Impact on the Pharmacology of MMT
title_sort population differences in the genetic polymorphism of cyp2b6 may impact on the pharmacology of mmt