Research design features and patient characteristics associated with the outcome of antidepressant clinical trials.


Journal Article

OBJECTIVE: The authors examined which, if any, research design features and patient characteristics would significantly differ between successful and unsuccessful antidepressant trials. METHOD: Clinical trial data were reviewed for nine antidepressants approved by the Food and Drug Administration between 1985 and 2000. From the antidepressant research programs on these medications, 52 clinical trials were included in the study. The authors evaluated trial design features, patient characteristics, and difference in response between placebo and antidepressant. RESULTS: Nine trial design features and patient characteristics were present in the research programs for all nine of the antidepressants. The severity of depressive symptoms before patient randomization, the dosing schedule (flexible versus fixed), the number of treatment arms, and the percentage of female patients were significantly associated with the difference in response to antidepressant and placebo. The duration of the antidepressant trial, number of patients per treatment arm, number of sites, and mean age of the patients were similar in successful trials (with a greater antidepressant-placebo difference) and less successful trials (with a smaller antidepressant-placebo difference). CONCLUSIONS: These findings may help in the design of future antidepressant trials.

Full Text

Duke Authors

Cited Authors

  • Khan, A; Kolts, RL; Thase, ME; Krishnan, KRR; Brown, W

Published Date

  • November 2004

Published In

Volume / Issue

  • 161 / 11

Start / End Page

  • 2045 - 2049

PubMed ID

  • 15514405

Pubmed Central ID

  • 15514405

International Standard Serial Number (ISSN)

  • 0002-953X

Digital Object Identifier (DOI)

  • 10.1176/appi.ajp.161.11.2045


  • eng

Conference Location

  • United States