Optimal Length of Continuation Therapy in Depression: A Prospective Assessment During Long-Term Fluoxetine Treatment

Abstract
Objective: The purpose of this study was to determine prospectively the optimal length of therapy in a long-term, placebo-controlled continuation study of patients who responded to acute fluoxetine treatment for major depression (defined by DSM-III-R). Method: The study was conducted at five outpatient psychiatric clinics in the United States. Patients who met criteria for remission after 12 or 14 weeks of open-label acute fluoxetine therapy, 20 mg/day (N=395 of 839 patients), were randomly assigned to one of four arms of a double-blind treatment study (50 weeks of placebo, 14 weeks of fluoxetine and then 36 weeks of placebo, 38 weeks of fluoxetine and then 12 weeks of placebo, or 50 weeks of fluoxetine). Relapse rate was the primary outcome measure. Both Kaplan-Meier estimates and observed relapse rates were assessed in three fixed 12-week intervals after double-blind transfers from fluoxetine to placebo at the start of the double-blind period and after 14 and 38 weeks of continued fluoxetine treatment.R...