Pfizer escapes hundreds of lawsuits alleging birth defects tied to Zoloft

Pfizer ($PFE) chalked up a big win in its courtroom saga over alleged birth defects tied to its antidepressant Zoloft. A federal judge agreed to dismiss the vast majority of claims against the company that link its drug to heart problems in infants.

U.S. District Judge Cynthia Rufe in Philadelphia dismissed more than 300 suits against Pfizer without a trial, leaving one case pending in the court, Bloomberg reports.

The company faces claims that Pfizer's antidepressant causes congenital heart defects in babies after their mothers take the med, and that Pfizer did not adequately warn patients about potential risks. Pfizer maintains that it kept the FDA and the public abreast of safety issues associated with Zoloft, and that there is no evidence confirming a link to birth defects.

"There is extensive science supporting the safety and efficacy of Zoloft, and the medicine carries accurate, science-based and FDA-approved information on its benefits and risks," the company told FiercePharma in a statement.

The latest win comes on the heels of other victories for Pfizer in cases over Zoloft. Last year, the company won two jury trials in St. Louis and Philadelphia over related claims and escaped paying $2.4 million in damages. Plaintiffs' lawyers in both cases tried to show that Pfizer knew that Zoloft could cause birth defects.

In the Philadelphia jury trial, lawyers put forth evidence showing that Pfizer scientists warned executives that there was a possible link between Zoloft and birth defects. The lawyers also pointed to a 1998 internal report, which showed that company researchers found more than a dozen side-effect reports about birth defects tied to Zoloft. Pfizer shot down the claims, pointing out that the drug's official label warns women against using the drug during pregnancy, the company said.

In yet another case in October, Pfizer scored a win after a Philadelphia state court judge dismissed a case brought by a couple who claimed that Zoloft caused birth defects in their son.

Still, regulators are taking note of potential safety problems with Zoloft and weighing in on the issue. In September, the FDA said that it wanted Pfizer to change the drug's label to reflect warnings from researchers who found an increased risk of congenital heart defects in infants whose mothers took Zoloft.

Pfizer is not the only company that has faced pushback over safety issues linked to its antidepressants. In 2010, GlaxoSmithKline ($GSK) paid more than $1 billion to settle hundreds of lawsuits claiming that its antidepressant Paxil increased the risk of birth defects. A couple of years later, a court in Canada approved a class-action case making similar claims, which set off a new round of investigations into the drug.

- read the Bloomberg story

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