Brain neurokinin-1 receptor availability in never-medicated patients with major depression - A pilot study.

BACKGROUND: Neurotransmitter substance P (SP) and its preferred neurokinin-1 receptor (NK1R) have been implicated in the treatment of affective and addiction disorders. Despite promising preclinical data on antidepressant action, the clinical trials of NK1R antagonists in major depression have been disappointing. There are no direct in vivo imaging studies on NK1R characteristics in patients with a major depressive disorder (MDD). METHODS: In this cross-sectional case-control study, we recruited nine never-medicated patients with moderate to severe MDD and nine matched healthy controls. NK1R availability (NK1R binding potential, BPND) was measured with in vivo 3-D positron emission tomography and a specific NK1 receptor tracer [18F]SPA-RQ. Clinical symptoms were assessed with the 17-item Hamilton Rating Scale for Depression (HAM-D17). RESULTS: NK1R-BPND did not differ statistically significantly between patients with MDD and healthy controls. HAM-D17 total scores (range 21-32) correlated positively with NK1R-BPND in cortical and limbic areas. HAM-D17 subscale score for anxiety symptoms correlated positively with NK1R-BPND in specific brain areas implicated in fear and anxiety. LIMITATIONS: Small sample size. Low variability in the clinical HAM-D subscale ratings may affect the observed correlations. CONCLUSIONS: Our preliminary results do not support a different baseline expression of NK1Rs in a representative sample of never-medicated patients with MDD during a current moderate/severe depressive episode. The modulatory effect of NK1Rs on affective symptoms is in line with early positive results on antidepressant action of NK1 antagonists. However, the effect is likely to be too weak for treatment of MDD with NK1R antagonists alone in clinical practice.

Deramciclane in the treatment of generalized anxiety disorder: a placebo-controlled, double-blind, dose-finding study.

Deramciclane, a camphor derivative, is a novel anxiolytic agent with a unique mechanism of action. It acts as a potent and specific antagonist at serotonin 5-HT2A/2C receptors, and exhibits anxiolytic efficacy in animal models. The aim of this double-blind, placebo-controlled, parallel-group study was to evaluate the efficacy, safety, and tolerability of a range of doses of deramciclane in patients with generalized anxiety disorder (GAD). Adult patients with a diagnosis of GAD (DSM-IV) and a Hamilton Anxiety Rating Scale (HAM-A) total score >or=18; a score >or=2 for the HAM-A items 'Anxious Mood' and 'Tension'; a score >or=4 on the Clinical Global Impression of Severity of Illness (CGI-S) Scale; and a score

Efficacy and tolerability of paroxetine for the long-term treatment of generalized anxiety disorder.

BACKGROUND: Paroxetine has demonstrated efficacy in depression and anxiety disorders, including generalized anxiety disorder (GAD). This 32-week study evaluated the maintained efficacy and safety of paroxetine in GAD by assessing the potential for relapse after discontinuation of medication. METHOD: Adults (N = 652) with DSM-IV GAD and a Clinical Global Impressions-Severity of Illness (CGI-S) score > or = 4 received paroxetine (20-50 mg/day) for 8 weeks. Patients whose CGI-S score had decreased by at least 2 points to < or = 3 at week 8 were randomly assigned to double-blind treatment with paroxetine (N = 278) or placebo (N = 288) for a further 24 weeks. The primary efficacy parameter was the proportion of patients relapsing (an increase in CGI-S score of at least 2 points to a score < or = 4 or withdrawal resulting from lack of efficacy) during double-blind treatment. RESULTS: Significantly fewer paroxetine than placebo patients relapsed during the 24-week double-blind phase (10.9% vs. 39.9%; p <.001). Placebo patients were almost 5 times more likely to relapse than paroxetine patients (estimated hazard ratio = 0.213 [95% CI = 0.1 to 0.3]; p <.001). Statistical significance in favor of paroxetine was demonstrated for all secondary efficacy parameters, including functional status. Twice as many paroxetine patients as placebo patients (73%) achieved remission. Paroxetine was well tolerated, with no unexpected adverse events reported. CONCLUSION: Paroxetine was found to be effective and well tolerated for both the short- and long-term treatment of DSM-IV GAD. Continued treatment with paroxetine significantly reduced the potential for relapse of GAD symptoms.

Relapse prevention with gepirone ER in outpatients with major depression.

To evaluate long-term efficacy and tolerability of the serotonin 5-HT1A receptor agonist, gepirone extended release (ER), a multicenter, randomized, placebo-controlled relapse prevention study was performed in patients with recurrent major depression (DSM-IV criteria). Patients 18 to 70 years, with a primary diagnosis of recurrent major depression (DSM-IV; 296.3) and a screening and baseline HAMD-17 total score >/=20 were eligible. After a 3- to 14-day (dependent on pretrial medication) single-blind placebo washout period, eligible patients entered an 8- or 12-week (depending on time to remission) open-label gepirone ER treatment period. They initially received a dose of 20 mg/d gepirone ER and were titrated to a dose of 40 to 80 mg/d. Patients who achieved remission (HAMD-17 total score /=16 or discontinuation for lack of efficacy. A total of 420 patients were treated in the open-label phase. Of these, 303 (72.1%) completed the open-label phase and 250 (59.5%) fulfilled the criteria for remission and were randomized into the double-blind continuation phase (gepirone ER: n = 126; placebo: n = 124). The mean (+/-SD) final titrated dose of gepirone ER was 61.9 (+/-17.0) mg/d in the double-blind continuation phase. The relapse rate in the gepirone ER group was statistically significantly lower than that in the placebo group, 23.0% versus 34.7%, respectively (P = 0.024). During the open-label phase, adverse events that occurred in more than 5% of patients were nausea (15.7%), dizziness (13.1%), headache (12.9%), insomnia (6.2%), and vertigo (6.0%). During the continuation phase, the incidence of newly or re-emerging adverse events was similar with gepirone ER (43.7%) and placebo (42.7%). Adverse events different from those occurring during the open-label phase were not apparent. All adverse events occurred in less than 5% of patients with the exception of flu syndrome and headache. In conclusion, gepirone ER at a dose range of 40 to 80 mg/d is effective for relapse prevention in patients with recurrent major depression. It is well tolerated during long-term treatment for up to approximately one year.