Objective: To investigate the impact of CYP2C19 genotype on serum concentrations of sertraline and N-desmethyl sertraline in psychiatric patients.
Methods: Patients treated with sertraline (n = 121) were divided into six subgroups according to CYP2C19 genotype: CYP2C19*17/*17, CYP2C19*1/*17, CYP2C19*1/*1, CYP2C19*17/def, CYP2C19*1/def and CYP2C19def/def (def = allele encoding defective CYP2C19 metabolism, i.e. *2 and *3). Dose-adjusted serum concentrations were compared by linear mixed model analyses using the CYP2C19*1/*1 subgroup as reference.
Results: Subgroups carrying one or two alleles encoding defective CYP2C19 metabolism achieved significantly higher mean dose-adjusted serum concentrations of sertraline and N-desmethyl sertraline compared to the CYP2C19*1/*1 subgroup (P < 0.05). The effect of CYP2C19 genotype was expressed as 3.2-fold (sertraline) and 4.5-fold (N-desmethyl sertraline) higher dose-adjusted serum concentrations in the CYP2C19def/def subgroup compared to the CYP2C19*1/*1 subgroup (P < 0.01). The CYP2C19*17 allele had no influence on the dose-adjusted serum concentrations of sertraline and N-desmethyl sertraline.
Conclusion: The significantly higher serum concentrations associated with alleles encoding defective CYP2C19 metabolism might be of relevance for the clinical outcome of sertraline treatment.