title: CYP2D6 P34S Polymorphism and Outcomes of Escitalopram Treatment in Koreans with Major Depression.
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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Psychiatry, College of Medicine, Korea University, Seoul, Republic of Korea. ; Pharmacogenetic Research Center for Psychotropic Drugs, Korea University, Seoul, Republic of Korea.
authors.forename: Kyu-Man
authors.initials: KM
authors.lastname: Han
authors.forename: Hun Soo
authors.initials: HS
authors.lastname: Chang
authors.forename: In-Kwang
authors.initials: IK
authors.lastname: Choi
authors.forename: Byung-Joo
authors.initials: BJ
authors.lastname: Ham
authors.forename: Min-Soo
authors.initials: MS
authors.lastname: Lee
keywords: CYP2D6 polymorphism; Escitalopram; Major depressive disorder; Treatment response