Suicide Risk and Symptom Reduction in Patients Assigned to Placebo in Duloxetine and Escitalopram Clinical Trials: Analysis of the FDA Summary Basis of Approval Reports

Background: We assessed suicide and suicide attempt risk as well as symptom reduction among 3,282 depressed patients participating in duloxetine and escitalopram clinical trials assigned to either an antidepressant or placebo.

Methods: We reviewed the FDA Summary Basis of Approval reports for data regarding safety and efficacy for duloxetine and escitalopram. Furthermore, we compared suicide risk among antidepressant clinical trials in this study with our two previous analyses on seven antidepressant clinical trials.

Results: Suicide and suicide attempt risk varied considerably among the three analyses, showing up to ten fold differences. Interestingly, the variability exists across the three reports, rather than between treatments (antidepressants versus placebo).

Conclusions: These findings suggest caution in generalizing suicide risk even from a relatively large number of participants and thus, firm conclusions can only be drawn if the number of participants is overwhelmingly large (approximately two million patients). We also noted similar magnitude of response to placebo and antidepressants among the three studies.