Pharmacogenetic investigation of response to duloxetine treatment in generalized anxiety disorder.

ABSTRACT

We examined genetic associations with duloxetine response in generalized anxiety disorder (GAD). Three pooled studies in patients with GAD receiving duloxetine 60-120 mg per day (N=164) or placebo (N=95) were used. Associations between 825 single-nucleotide polymorphisms (SNPs) in 61 candidate genes with change in Hamilton Anxiety Scale scores were examined with set-based testing (adjusted for the number of SNPs within each gene); sets with two-sided adjusted P≤0.05 were examined using repeated measure analysis. Follow-up analysis explored associations of these SNPs with change in Hamilton Rating Scale for Depression-Anxiety Subscale in a 6-week study in duloxetine-treated patients with major depressive disorder (MDD) (N=241). Variants in corticotropin-releasing hormone receptor 1 (CRHR1), dopamine receptor D3 (DRD3), nuclear receptor subfamily group C, member 1 (NR3C1) and phosphodiesterase 1A (PDE1A) were associated with duloxetine response in GAD. Only rs4792888 in CRHR1 showed modest evidence of association with duloxetine response in MDD (P=0.029 in GAD, P=0.054 in MDD). In conclusion, CRHR1 variation merits investigation in pathophysiology of anxiety and its treatment response.