Court Rules Studies Don’t Support Cirrhosis/Acetaminophen Link
This article was originally published in The Tan Sheet
A few observational case studies are not enough to prove prolonged therapeutic use of Tylenol (acetaminophen) was sufficient to cause a plaintiff’s liver damage, a New York state court ruled in a case brought against McNeil Consumer Healthcare.
The appellate division of New York’s Supreme Court ruled the Supreme Court properly determined that the Johnson & Johnson division “met its burden by demonstrating that there was no evidence linking acetaminophen to cirrhosis,” Judge John Leventhal wrote in the unanimous Nov. 22 opinion in Ratner v. McNeil-PPC.
Plaintiff Margalit Ratner said she used Tylenol and Extra Strength Tylenol beginning in 1985 to relieve migraine headaches but never exceeded the maximum recommended dose. She began having liver trouble in 1997 and eventually needed a liver transplant in 2004.
Four experts were prepared to testify on Ratner’s behalf, two “to set forth the theory” that her acetaminophen use caused her liver cirrhosis, Leventhal wrote. One relied upon, among other evidence, “four case studies performed on mice and rats” while another planned to rely on “scientific publications and literature which he asserted indicated that acetaminophen could cause hepatitis, fibrosis and cirrhosis.”
An expert for McNeil said the medical literature Ratner’s experts intended to rely upon “consisted almost exclusively of case reports and animal studies about acetaminophen overdose, and that such data about overdoses could not be extrapolated to explain the cause of the plaintiff’s condition.”
When admitting novel science into evidence, New York courts apply a standard laid out in Frye v. United States, which permits “expert testimony based on scientific principles, procedures or theories only after the principles, procedures or theories have gained general acceptance in the relevant scientific field,” Leventhal wrote. The burden of proving tests are accepted in the scientific community rests with the party presenting the evidence.
The Frye test also has been applied to social and behavioral theories, so when as in this case, a plaintiff’s experts intend to testify about “a novel theory of causation” – that chronic therapeutic doses of acetaminophen cause liver damage – the appropriate evidentiary standard is “whether the theory is properly founded on generally accepted scientific methods or principles,” Leventhal added.
McNeil did not dispute that there is scientific support for the theory that a massive overdose of acetaminophen can cause liver failure but asserted there is “no scientific support for the general theory that acetaminophen taken within recommended doses can cause cirrhosis of the liver and, therefore, that there is no support for the specific theory that the plaintiff’s cirrhosis is attributable to acetaminophen.”
The court agreed with McNeil. “We find that the data upon which the plaintiff’s experts relied is insufficient to support their novel theory of medical causation, rendering that theory speculative.”
The plaintiff introduced only two case reports of individuals that linked therapeutic doses of acetaminophen and liver cirrhosis in otherwise healthy subjects, Leventhal wrote. The studies “constitute merely observational data which are of a lesser caliber than controlled clinical studies from which results can be reviewed and verified” and “do not unequivocally state that acetaminophen caused the liver cirrhosis observed therein.”
McNeil in July lowered the maximum daily dose for its Tylenol products (Also see "McNeil Lowers Recommended Maximum Dose For Extra Strength Tylenol" - Pink Sheet, 1 Aug, 2011.).
Ratner sought to recover damages for negligence, failure to warn, defective design, breach of implied and express warranties and a violation of New York’s general business law. She can appeal the case to the Court of Appeals, New York’s highest state court.