Decreased suicide rates in recent antidepressant clinical trials.
Khan, A., Mar, K., Gokul, S. & Brown, W.
Rationale The last systematic analysis of suicidality in antidepressant clinical trials submitted for approval by the US Food and
Drug Administration was in 2000. Given the attention to suicide and antidepressants in the early 2000s, the authors aimed to
evaluate if there have been any changes in suicide rates in antidepressant clinical trials following 2000.
Objective and Methods The Integrated Safety Summary data from approval packets for 14 investigational antidepressant
programs (1991–2013, 40,857 patients, 10,890.5 exposure years) were used to calculate suicides and suicide attempts per
100,000 patient exposure years (standardized rates) for antidepressant and placebo treatment groups separately. Suicides/
suicide attempt rates, mean age, and percent female were compared between 1991 and 1998 (pre-2000) and 2002–2013 (post2000).
Drug-placebo differences in suicide/suicide attempt rates were explored.
Results Among antidepressant-treated patients, the standardized suicide rate decreased significantly from pre- to post-2000
(643.6 to 25.8, p < 0.0001) as did the standardized suicide attempt rate (3975.7 to 645.4, p < 0.0001). For placebo-treated
patients, the decrease was not significant for suicide rate (471.1 to 174.2, p = 0.66) but was significant for suicide attempt rate
(from 3538.3 to 522.6, p < 0.001). Regression analysis showed a similar pattern with suicide/suicide attempt rates decreasing
over time. None of the drug-placebo comparisons in suicide or suicide attempt rates were statistically significant. There was no
change in percent female or mean age of patients in trials pre- and post-2000.
Conclusions Deaths by suicide and suicide attempts have decreased significantly in antidepressant clinical trials following 2000
compared to the decade before 2000. Basic demographic features of the patients have remained consistent and medication
treatment effects on suicidality were not apparent. These findings may reflect enhanced screening procedures and effective
exclusion of suicidal patients in clinical trials for depression.