Both drugs are antidepressants in the selective serotonin reuptake inhibitor (SSRI) class, and like other SSRIs have been shown to significantly increase the risk of suicidal thoughts and behaviors in children, adolescents and young adults after even short-term use.
Lexapro is the 15th biggest selling drug in the United States.
On March 20, the FDA approved Lexapro for the treatment of major depressive disorder in children between the ages of 12 and 17, based on the findings of only one clinical study. Another study showed the drug to have no more effect than a placebo.
"A lot of these kinds of trials are not successful because it's very difficult to do depression studies," said Forest spokesman Frank Murdolo. "But we have two studies that were successful."
The second study referenced by Murdolo was conducted on Celexa, which the FDA declined to approve for use in children. A second Celexa study found no evidence that the drug was effective.
The FDA also approved Lexapro as a way to maintain control of depression symptoms, even though Forest admits there is no clinical evidence for that benefit in children. The FDA argued that it was possible to extrapolate the effectiveness of the drug from adult studies.
Lexapro is only the second antidepressant to receive US approval for use in children.
According to a federal complaint however, Forest has been marketing Lexapro and Celexa to children illegally for at least nine years.
In 1999, the FDA asked the company to conduct two independent clinical trials into Celexa's effectiveness in children, offering as incentive a six-month patent extension. Forest commissioned two studies -- one by the Danish company Lundbeck, which initially developed the drug, and another by U.S. researcher Karen Dineen Wagner.
While the Wagner study found "a statistically ... significant reduction in depressive symptoms in children and adolescents" and "no serious adverse events" from the drug's use, the Lundbeck study found that Celexa provided no benefits over the placebo. In addition, out of a total participant population of 244 in the Lundbeck study, nine more Celexa patients attempted or considered suicide compared with those taking a placebo.
For the next three years, however, Forest widely publicized the Wagner study but did not disclose the results of the Lundbeck study.
The complaint also accuses Forest of carrying out a "widespread campaign to promote the drugs for pediatric use by paying pediatric specialists to give promotional speeches to other physicians ... and by selectively distributing publications on pediatric uses, among other strategies."
Between 2000 and 2005, Forest hosted more than 900 "advisory boards" across the country about the use of the two antidepressants, paying more than 19,000 attendees $500 each. Other payments made to pediatricians included fishing trips, spa visits and tickets to sports games or Broadway shows.
Sources for this story include: www.reuters.com; www.psychiatrictimes.com.