Two to 3 percent of children treated with antidepressants had suicidal thoughts or behavior as a result of the drugs, officials said yesterday based on the Food and Drug Administration's most comprehensive analysis of past clinical trials of the widely used drugs.
In a sharp departure from a decade-old position, agency officials said the increase in suicidal tendencies was not a result of the children's underlying depression but was caused by the medications themselves.
"Out of 100 patients treated, we may expect to see two to three patients [who] will experience increases in suicidality due to short-term treatment," said Tarek A. Hammad, the FDA analyst who conducted the latest review. The increase, he said, "is beyond the suicidality as a result of the disease being treated."
Senior FDA officials acknowledged that the results of the new analysis were substantially the same as the conclusions more than seven months ago of an agency scientist who also found an increase in suicidal tendencies in children taking the medications. At the time, the agency declined to make the conclusions of staff scientist Andrew D. Mosholder public, citing a lack of confidence in his results.
Hammad spoke at a meeting of an FDA expert advisory board that began a two-day hearing yesterday on the controversy over the reported risks of prescribing the widely used antidepressants to young people.
Robert J. Temple, the FDA's associate director for medical policy, defended the decision to hold off presenting Mosholder's controversial conclusions in March.
"Obviously people can disagree," he said. At a news briefing that included Mosholder and Hammad, Temple added: "We are cognizant that taking these drugs might increase suicidal ideation. But depression alone is a cause of potential suicide, so scaring people needlessly and overdoing it is worrisome also."
Parents and other critics of the agency had accused senior officials of turning a blind eye to the worrisome data. But Temple, Hammad and Mosholder agreed that the studies lent themselves to differing interpretations, in part because they were not originally designed to answer questions about suicidal tendencies. While individual clinical trials sometimes contradicted each other, the FDA officials said a broad pattern of evidence had emerged that, on average, children taking the medications had about twice the risk of developing suicidal behavior or thoughts as children receiving sugar pills, or placebos.
"It's very consistent," Temple said, adding that regulators would examine today whether the drugs' labeling should be modified and whether some drugs for children should be recommended to physicians ahead of others.
The controversy over the drugs is the subject of several congressional inquiries. Physicians and families have complained that pharmaceutical companies kept secret the results of more than half the trials that found the drugs were no more effective than placebos.