title: Fluticasone propionate pharmacogenetics: CYP3A4*22 polymorphism and pediatric asthma control.
abstract: OBJECTIVE
  To determine the relationship between allelic variations in genes involved in fluticasone propionate (FP) metabolism and asthma control among children with asthma managed with inhaled FP.
  
  
  METHODS
  The relationship between variability in asthma control scores and genetic variation in drug metabolism was assessed by genotyping 9 single nucleotide polymorphisms in the CYP3A4, CYP3A5, and CYP3A7 genes. Genotype information was compared with asthma control scores (0=well controlled to 15=poorly controlled), determined using a questionnaire modified from the National Heart Lung and Blood Institute's Expert Panel 3 guidelines.
  
  
  RESULTS
  Our study cohort comprised 734 children with asthma (mean age, 8.8±4.3 years) and was predominantly male (61%) and non-Hispanic white (53%). More than one-half of the children (56%; n=413) were receiving an inhaled glucocorticoid daily, with FP the most frequently prescribed agent (65%). Among the children receiving daily FP, single nucleotide polymorphisms in CYP3A5 and CYP3A7 were not associated with asthma control scores. In contrast, asthma control scores were significantly improved in the 20 children (7%) with the CYP3A4*22 allele (median, 3; range, 0-6) compared with the 201 children without the CYP3A4*22 allele (median, 4; range, 0-15; P=.02). The presence of CYP3A4*22 was associated with improved asthma control scores by 2.1 points (95% CI, 0.5-3.8).
  
  
  CONCLUSIONS
  The presence of CYP3A4*22, which is associated with decreased hepatic CYP3A4 expression and activity, was accompanied by improved asthma control in the FP-treated children. Decreased CYP3A4 activity may improve asthma control with inhaled FP.
authors.affiliation: Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA.
authors.forename: Chris
authors.initials: C
authors.lastname: Stockmann
authors.forename: Bernhard
authors.initials: B
authors.lastname: Fassl
authors.forename: Roger
authors.initials: R
authors.lastname: Gaedigk
authors.forename: Flory
authors.initials: F
authors.lastname: Nkoy
authors.forename: Derek A
authors.initials: DA
authors.lastname: Uchida
authors.forename: Steven
authors.initials: S
authors.lastname: Monson
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Reilly
authors.forename: J Steven
authors.initials: JS
authors.lastname: Leeder
authors.forename: Garold S
authors.initials: GS
authors.lastname: Yost
authors.forename: Robert M
authors.initials: RM
authors.lastname: Ward
mesh_terms: D000280:Administration, Inhalation; D000293:Adolescent; D000730:Androstadienes / Q000008:administration & dosage / Q000493:pharmacokinetics*; D001249:Asthma / Q000188:drug therapy*; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D002648:Child; D002675:Child, Preschool; D051544:Cytochrome P-450 CYP3A / Q000235:genetics*; D005260:Female; D000068298:Fluticasone; D006801:Humans; D008297:Male; D010597:Pharmacogenetics; D011110:Polymorphism, Genetic; D011446:Prospective Studies; D011795:Surveys and Questionnaires
chemical_list: D000730:Androstadienes; D001993:Bronchodilator Agents; D000068298:Fluticasone; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human