Daubert Hearings Challenging Opinions About Tylenol Prenatal Exposure Risks To Be Considered By MDL Judge Dec. 7

The U.S. District Judge presiding over all Tylenol lawsuits will hold a hearing this week to determine whether several of the plaintiffs’ expert witnesses will be allowed to testify at trial about the link between prenatal exposure to acetaminophen and the development of autism and attention deficit hyperactivity disorder (ADHD) among children.

Tylenol (acetaminophen) has been widely used by pregnant women for decades, largely due to the widespread belief that it is safe for unborn children. However, a growing number of lawsuits are now being pursued by families nationwide, each raising similar allegations that drug makers failed to adequately warn pregnant women about the growing evidence that in utero Tylenol prenatal exposure may cause autism or ADHD.

Given common questions of fact and law over the adequacy of the Tylenol pregnancy warnings, the U.S. Judicial Panel on Multidistrict Litigation (JPML) established coordinated pretrial proceedings last year, centralizing all claims brought throughout the federal court system before U.S. District Judge Denise Cote in the Southern District of New York, as part of a federal multidistrict litigation (MDL).

As part of the coordinated pretrial proceedings, Judge Cote has prioritized discovery into the link between Tylenol and autism, as well as ADHD and other developmental problems. However, the size and scope of the litigation continues to increase as families realize that their child’s diagnosis may have resulted from exposure to acetaminophen before birth.

Tylenol Lawsuit Daubert Hearings

During a three hour hearing on December 7, Judge Cote will hear arguments from both sides about whether the testimony provided by certain expert witnesses proposed by the plaintiffs is sufficiently reliable to present to a jury at trial, which are known as Daubert hearings.

The U.S. Supreme Court has established the standard for admissibility of expert testimony in the federal court system with a series of rulings, starting with Daubert v Merrell Dow Pharmaceuticals, Inc., which allows the judge to act as a gatekeeper, ensuring that testimony presented is relevant and based on a sound scientific foundation.

In September, defendants filed a Rule 702 motion (PDF), seeking to exclude five plaintiffs’ expert witnesses. The manufacturers and sellers of Tylenol claim that the plaintiffs’ experts rely on speculative science to determine that Tylenol causes autism, using very limited medical and scientific literature. The motion also claims that plaintiffs’ witnesses ignored better-conducted studies that contradict their findings.

The defendants called for a Daubert hearing in an October 2 letter (PDF), asking for a week of testimony, including live witnesses, starting on December 4. They sought to give 20 hours to each side for direct and cross examination, and 90 minutes of closing arguments.

Plaintiffs protested these conditions in a response letter (PDF) submitted the same day.

“The parties’ expert witnesses in this case have been cumulatively subject to over 80 hours of cross examination.” The letter notes. “Plaintiffs see no need for the time and expense associated with preparing for and conducting a week-long hearing to supplement the extensive Rule 702 record if such a proceeding will not most efficiently assist the Court in resolving the pending motions.”

Judge Cote determined that a short Daubert hearing was sufficient in a hearing order (PDF) issued on November 7, mostly siding with plaintiffs and setting the Daubert arguments for December 7. The judge has given each party only three hours of oral argument and ruled that the Court does not require the testimony of any of plaintiffs’ expert witnesses.

December 2023 Tylenol Autism and ADHD Lawsuit Update

If plaintiffs’ expert witnesses are approved to testify at trial after the Daubert hearings, the litigation over the manufacturers’ failure to warn about the risk of ADHD and autism from Tylenol will be cleared to move forward.

Unless the drug makers are able to entirely dismiss the lawsuits at this stage, it is expected that Judge Cote will then establish a “bellwether” process, where a small group of representative cases will be selected for early trial dates, to help gauge how juries may respond to certain evidence and testimony that will be repeated throughout the litigation.

Although the outcome of such bellwether trials will not be binding on other families pursuing lawsuits, the average payouts awarded by juries may influence the amount of any Tylenol settlements Johnson & Johnson and other drug makers may offer families in the future, to avoid the need for each individual case to go to trial in the coming years.