 Participants are tapered off anti-depression drugs and any other medications not allowed on the study over a 3-week period and then begin a 2-week drug-free period. During these 2 weeks they have an electroencephalogram EEG with light stimulation, and those whose EEG indicates a seizure disorder are excluded from the study. Also at the beginning of the drug-free period they begin taking a placebo sugar pill twice a day. After 2 weeks on placebo, some patients begin treatment with Org 24448, while others remain on placebo. They continue the medication for 8 weeks, during which time they have a weekly check of vital signs, blood and urine tests, and rating scales for depression and anxiety. Level of functioning is evaluated twice during the study. After 8 weeks of treatment, patients have a physical exam, electrocardiogram ECG, EEG, blood tests, and begin to come off the study drug, tapering the medication over a week. 