Zoloft lawyers accuse Pfizer of hiding birth-defect risks

Pfizer researchers found evidence last year that pregnant women using its Zoloft antidepressant had a higher risk of giving birth to a child with heart problems and other congenital anomalies, Bloomberg reports. Now, the internal report has surfaced in a lawsuit blaming Zoloft for a young boy's heart defect, the first such case to go to trial.

Lawyers for the 11-year-old Logyn Pesante and his mother flagged the May 2014 report, saying that it helps show Pfizer ($PFE) didn't properly warn about the risks of its drug. According to the report, Zoloft poses risks of a variety of health problems, including structural defects in the heart and digestive system, and congenital heart and lung disease.

Pfizer, however, says the plaintiffs' lawyers took "a single statement in one document, summarizing the results of few studies, out of context," Bloomberg reports. One of its lawyers, Beth Wilkinson, said in court that, "The science has never even suggested that birth defects were caused by Zoloft."

An expert witness for Pesante testified that his own review of the data persuaded him that Zoloft was "a risk factor for birth defects," the news service says. Dr. Robert Cabrera, a doctor at a University of Texas institute researching birth defects, also pointed to a 2007 study in the New England Journal of Medicine that found twice the risk of birth defects in infants born to Zoloft patients.

Wilkinson said Pfizer warned about pregnant women's use of the drug on its official FDA-approved label. The agency has never ordered the company to amp up its warnings about those risks, the lawyer said.

"[A] comprehensive review of the literature did not support an association between use of Zoloft and birth defects, including cardiac anomalies," Pfizer told Bloomberg.

Pesante's case is just one of more than 1,000 pending. The two sides have been fighting over expert witnesses and their research, with a variety of experts barred last fall for failing to use proper methods for analyzing data.

- read the Bloomberg coverage

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