Symptom Reduction and Suicide Risk in Patients Treated With Placebo in Antidepressant Clinical Trials

The assumption that depressed patients who are assigned to placebo in antidepressant clinical trials are exposed to substantial morbidity and mortality is not based on research data. We assessed suicides, suicide attempts, and depressive symptom reduction in studies of 7 new antidepressants using the Food and Drug Administration database. Among 19,639 participating patients, 34 committed suicide (0.8% per year), and 130 attempted suicide (2.9% per year). Rates of suicide and attempted suicide did not differ significantly among the placebo- and drug-treated groups. Annual rates of suicide and attempted suicide were 0.4% and 2.7% with placebo, 0.7% and 3.4% with active comparators, and 0.8% and 2.8% with investigational antidepressants, respectively. Symptom reduction was 40.7% with investigational drugs (n = 4,510), 41.7% with active comparators (n = 1,416), and 30.9% with placebo (n = 2,805). These data may help inform discussions about the use of placebo in antidepressant clinical trials.