Ziprasidone Augmentation of SSRIs for Patients With Major Depressive Disorder (MDD) That do Not Sufficiently Respond to Treatment With SSRIs

The proposed study involves three phases. The first phase is an 8-week, open-label trial of an SSRI for MDD. Patients who do not experience sufficient symptom improvement following this open-label trial will be enrolled in a 6-week, double-blind, placebo controlled trial of ziprasidone augmentation (second phase). Ziprasidone and placebo-remitters will then enter a 12-month, double-blind extension phase (third phase). We estimate that approximately 400 patients will enter phase 1 of the study so that a minimum of 180 subjects will enter double-blind treatment (phase 2) over 5 years. Each treatment arm during phase 2 will have 90 subjects. Hypothesis B1: During phase 2, there will be a difference between the two groups in the percentage of responders (50% or greater reduction in symptom severity) with regards to anxious symptoms of MDD as measured by the 14-item Hamilton Anxiety Rating Scale (HAM-A); response rates will be higher for the ziprasidone group. Hypothesis B2: During phase 2, there will be a difference between the two groups in the percentage of responders (50% or greater reduction in symptom severity) with regards to painful symptoms of MDD, as measured by the overall visual analogue pain (VAS-pain) scale scores; response rates will be higher for the ziprasidone group. Hypothesis C: The time to relapse during phase 3 will be shorter among adjunctive placebo- than ziprasidone-remitters.