Adjunctive L-methylfolate at 15 mg/day may constitute an effective, safe, and relatively well tolerated treatment strategy for patients with major depressive disorder who have a partial response or no response to SSRIs.

Treatment of GAD with an antidepressant should be continued for at least 12 months. Preliminary data demonstrate that improved patients who relapse while off their antianxiety medication after at least 6 months of treatment will again most likely respond to a second course of treatment with the same medication. Trial Registration clinicaltrials.gov Identifier: NCT00183274.

This 8-week, randomized, double-blind, placebo-controlled, flexible-dose trial assessed the efficacy, safety, and tolerability of ziprasidone in adults with treatment-resistant generalized anxiety disorder (GAD). Seventy-three subjects with treatment-resistant GAD were recruited, and 62 were randomized to either ziprasidone or placebo treatment at a ratio of 2:1 using a flexible dosing strategy (20-80 mg daily). Randomization was stratified into 2 subtypes of patients, those in whom the study drug was used as augmentation and those who have stopped their ineffective medications before entering the present trial (nonaugmented group). The subjects' clinical status was monitored weekly throughout the course of the study and included the Hamilton Anxiety Scale (primary outcome measure), the Clinical Global Impression Improvement and Severity of Illness scales, the Hamilton Depression Scale, the Sheehan Disability Scale, the Hospital Anxiety and Depression Scale, and the Abnormal Involuntary Movements Scale. Sixty-two patients were randomized to ziprasidone (n = 41) or placebo (n = 21). The dropout rate was 24%, consisting of 2 placebo patients and 13 ziprasidone patients. There was no statistically significant difference in the Hamilton Anxiety Scale score reduction between the drug and placebo groups. However, statistical trends were observed for an augmentation-study medication interaction effect, with ziprasidone patients producing more improvement in the nonaugmented than in the augmented group. This study provides pilot data for an augmentation-study medication interaction effect with ziprasidone patients producing more improvement in the nonaugmented than in the augmented group. Based on the data obtained in this trial and the subsequent power analyses, a future double-blind placebo-controlled trial should include at least 150 treatment-resistant GAD nonaugmented patients randomized to ziprasidone and placebo in a 1:1 ratio.

Generalized anxiety disorder (GAD) is a chronic psychiatric disorder with significant morbidity and mortality. Antidepressant drugs are the preferred choice for treatment; however, treatment response is often variable. Several studies in major depression have implicated a role of the serotonin receptor gene (HTR2A) in treatment response to antidepressants. We tested the hypothesis that the genetic polymorphism rs7997012 in the HTR2A gene predicts treatment outcome in GAD patients treated with venlafaxine XR. Treatment response was assessed in 156 patients that participated in a 6-month open-label clinical trial of venlafaxine XR for GAD. Primary analysis included Hamilton Anxiety Scale (HAM-A) reduction at 6 months. Secondary outcome measure was the Clinical Global Impression of Improvement (CGI-I) score at 6 months. Genotype and allele frequencies were compared between groups using χ(2) contingency analysis. The frequency of the G-allele differed significantly between responders (70%) and nonresponders (56%) at 6 months (P=0.05) using the HAM-A scale as outcome measure. Similarly, using the CGI-I as outcome, the G-allele was significantly associated with improvement (P=0.01). Assuming a dominant effect of the G-allele, improvement differed significantly between groups (P=0.001, odds ratio=4.72). Similar trends were observed for remission although not statistically significant. We show for the first time a pharmacogenetic effect of the HTR2A rs7997012 variant in anxiety disorders, suggesting that pharmacogenetic effects cross diagnostic categories. Our data document that individuals with the HTR2A rs7997012 single nucleotide polymorphism G-allele have better treatment outcome over time. Future studies with larger sample sizes are necessary to further characterize this effect in treatment response to antidepressants in GAD.