Depression, Depressionen

Vagus-Nerv-Stimulation (VNS):

VNS THERAPY NEWS FLASH - ISSUE 14 - MARCH 2004

VNS Therapy for Major Depression: Results from the European Multicenter Trial D-03

42 adult outpatients with non-psychotic treatment-resistant major depressive (n = 34) or bipolar I or II (n=8, depressed phase) disorders were included in this European multicenter trial. Patients had failed at least two robust medication trials in the current major depressive episode (MDE) while on stable medication regimens. All patients completed a baseline period followed by VNS Therapy implantation. A 2-week single-blind recovery period with no stimulation was followed by 10 weeks of VNS Therapy.

Results:

Acute response rates (50% reduction in baseline scores) was 48% for the 28 Hamilton Depression Rating Scale (HDRS28). Symptomatic responses accompanied by substantial functional improvement have been largely sustained during longer-term follow-up for 12 months.

The author concludes that the data from this European pilot study on VNS Therapy in depression, strongly suggest a sustained antidepressant effect in treatment resistant major depression. According to the author: “If these findings can be confirmed in more rigorously designed studies, VNS Therapy could become a key treatment option for a subgroup of refractory patients”.

Source: Thomas E. Schlaepfer et al., Abstract presented at the Annual American College of Neuropsychopharmacology Congress (ACNP), December 2003, Puerto Rico.

A One-Year Longitudinal Study of VNS Therapy in Patients with Treatment-Resistant Depression

The double-blind, randomised, 10-week acute study (D-02) of VNS Therapy for patients with treatment-resistant depression, did not demonstrate a statistically significant difference on HRSD24 response rates between treatment (15%) and sham (10%). After completion of this 10-week double-blind acute trial, patients could continue in an open-label long-term phase of the study.

In this long-term study, patients in the treatment group continued VNS Therapy and patients in the sham group (delayed treatment) began stimulation. Patients in the delayed treatment group were required to meet the same entry criteria as required of those who received VNS Therapy at the initial treatment.

177 patients with treatment-resistant depression who had completed at least 12 months of VNS Therapy were included in this analysis. Patients were seen monthly for the first year of VNS Therapy and completed efficacy, safety, and quality of life assessments. A priori definitions of response were defined as a 50% decrease in HRSD24 and IDS-SR30 raw scores from baseline.

Results:

• Response defined as a 50% decrease in total raw scores between baseline and 1 year.

• Remission defined as an IDS-SR30 14, HRSD24 9, and MADRS 10 at 1 year.

• Clinical benefit was measured by improvement on the HRSD24: Extraordinary ( 75%), Highly Meaningful (50% to <75%), Meaningful (25% to <50%), Minimal (0% to <25%), Worsened (<0%)

• Clinical benefit was greater at 12 months compared with 3 months (Stuart-Maxwell test, p<0.001)

Variable 12-Month Change from Baseline 12-Month Change from 3 Months Mental Component Vitality Improvements ++ ++ Social Function ++ ++ Role Emotional ++ + Mental Health ++ ++ Physical Component Physical Function + Role Function-Physical Pain index Health Perceptions +

• Improvement in depression is supported by improved quality of life at 12 months as measured by the SF-36.

• Change from 3 months of VNS Therapy to 1 year shows additional improvement.

Stimulation-related adverse events reported early in the course of VNS Therapy were reported with less frequency over time.

The author concluded that during long-term VNS Therapy, patients exhibited statistically significant and clinically meaningful improvement and that patients continued to improve over time as seen with different assessments. According to the author: “VNS Therapy appears to be a safe and effective therapy for patients with treatment-resistant depression”.

Source: A. John Rush et al., Abstract presented at the Annual American College of Neuropsychopharmacology Congress (ACNP), December 2003, Puerto Rico.

EUROPEAN INTENDED USE / INDICATION FOR DEPRESSION

The VNS Therapy System is indicated for treatment of chronic or recurrent depression in patients that are in treatment-resistant or treatment-intolerant major depressive episode.