Examination of a Soy-Based Supplement for Major Depression

The purpose of this study is to find out if the soy-based dietary supplement Novasoy (Registered Trademark) is effective for the short-term treatment of clinical depression. This study will also evaluate whether Novasoy (Registered Trademark) is effective in treating the anxiety that often accompanies depression and will assess the best dose level. Novasoy (Registered Trademark) is a marketed botanical dietary supplement containing soy isoflavones. The active form of the soy isoflavone genistin may be a novel treatment for neuropsychiatric illnesses. The soy isoflavone's specific hormonal properties may also have beneficial effects on brain function in depressed patients. This study will be conducted in two phases. During Phase I, participants will stop all medications for at least 1 week. A psychiatric and medical examination will be conducted. During Phase II, participants will be randomly assigned to receive either Novasoy (Registered Trademark) or a placebo (an inactive pill) for 8 weeks. Participants who do not respond to treatment after 5 weeks will be given a higher dose of their assigned medication. After the 8-week period, participants will be monitored for up to 3 months before being referred back to their clinician for further treatment.