The multidistrict litigation (MDL) involving Zoloft birth defects lawsuits against drug giant Pfizer has again been delayed. U.S. District Judge Cynthia Rufe of the Eastern Disctrict of Pennsylvania in Philadelphia has continued a Daubert hearing in the Zoloft MDL to September in response to a Pfizer expert’s claimed discovery of alleged data errors in an earlier study of Zoloft heart defects risks.
Defendant Pfizer’s medical Expert, Dr. Stephen E. Kimmel, wrote a report alleging that one of two independent studies claiming that Zoloft increases the risk of heart defects in newborns contains allegedly incorrect data. Kimmel wrote that he contacted the author of the article that appeared in the New England Journal of Medicine.
According to Kimmel’s report, the author of the article later confirmed there were errors and contacted the Journal to issue corrections. Kimmel wrote that the article’s original position of statistical significance supporting claims that Zoloft increased the risk of congenital heart defects was invalid.
Given the recent discovery, Judge Rufe ordered that the remainder of the hearing would be put off until September so the plaintiffs could have the opportunity to conduct more discovery and depositions.
The proceeding, known as a Daubert hearing, allows parties to challenge the admissibility of expert testimony before the start of a trial. There were about 550 cases as of June 1 in the multi district litigation. But in the time leading up to the hearing, dozens of cases had been dismissed without prejudice.
Judge Rufe ruled in May that the plaintiffs had to turn over a report their expert produced in similar litigation involving Prozac. The plaintiffs handed over the report and testimony of Dr. Nicholas Jewell involving a Prozac case in the Western District of North Carolina.
Dr. Jewell is the plaintiffs’ second causation expert used. The first one, Anick Bérard, was rejected after a week-long Daubert hearing last year. It was an unusual move for the judge to allow a second expert to be proffered in the case.
The plaintiff in the Prozac case alleged her son was born with a supracristal ventricular septal defect, a problem in the wall between the left and right sides of the heart. The mother alleged that she had taken Prozac during her pregnancy.
About 60 percent of the cases that are part of the Zoloft litigation involve claims of cardiac defects. Both Zoloft and Prozac are in a class of antidepressant drugs known as selective serotonin reuptake inhibitors (SSRI antidepressants), but the parties disagree about how similarly the drugs operate. Pfizer argues that plaintiffs are trying to hide inconsistencies in the methodologies used in the two different drug cases.