Which depressed patients respond to nefazodone and when?

Background: Retrospective data analyses were conducted of a single-blind tr ial of 993 outpatients with nonpsychotic major depression (DSM-III-R) treat ed for 12 weeks with nefazodone to provide a more specific picture of the n ature and timing of response or remission to acute-phase treatment. Method: All patients participated in a single-blind, 16-week lead-in to obt ain responders eligible for a subsequent double-blind, randomized continuat ion phase trial. Outcomes were defined by the 17-item Hamilton Rating Scale for Depression (HAM-D). A greater than or equal to 50% reduction from base line defined response, and a total HAM-D exit score of less than or equal t o 8 defined remission. Results: Of all patients who entered the trial, 41.8% (last observation car ried forward) responded at or before week 4 (early responders), and an addi tional 25.2% responded thereafter. 18.3% achieved remission at or before we ek 4; 33.6% achieved remission after week 4. Thus, 77.3% of those respondin g ultimately remitted. On average, remission followed response by 2 weeks. The average end-of-treatment dose was 376 mg/day at exit (last observation curried for ward). Responders or remitters (as opposed to nonresponders or nonremitters) had lower baseline depressive symptomatology and were more li kely to be married or cohabiting. Conclusion: The full symptomatic benefit of antidepressant medication may n ot be apparent until completion of an 8- to 10-week trial. A high number of responders ultimately attained remission. Baseline demographic and clinica l features were not highly predictive of who would or would not benefit fro m nefazodone. For routine care, a minimal acute-phase trial, using a 50% re duction in baseline symptom severity to define response, should be 8 weeks. Whether ultimate nonresponders can be identified earlier than 8 weeks dese rves further study.