Delaware Court Sides With Zantac Makers on Cancer Claims

The Delaware Supreme Court rejected the legitimacy of expert testimony linking the heartburn drug Zantac to cancer, in a major win for makers of the product.

In a unanimous ruling Thursday, the state’s highest court agreed with the argument of companies including GSK Plc, Pfizer Inc. and Boehringer Ingelheim Pharmaceuticals that Superior Court Judge Vivian Medinilla erred in allowing the cancer testimony and letting the cases proceed to trial.

“A trial judge must act as the gatekeeper of expert testimony and should not dismiss challenges to the sufficiency or reliability of an expert opinion by viewing the disputes as questions for the jury to weigh,” the state’s highest court said in a 46-page ruling.

Last year, GSK offered more than $2 billion to settle its Zantac liability, while Pfizer and French drugmaker Sanofi have pushed to resolve thousands of suits. GSK’s settlement resolved the vast majority of outstanding cases for the UK pharmaceutical company, with the latest ruling only impacting a handful of remaining cases in Delaware. Boehringer’s pharmaceuticals unit has settled only a small share of the cases against it. The company has prevailed in several recent trials over the cancer claims.

GSK and Sanofi shares were little changed in early trading. GSK’s shares have gained 8% since the start of the year, while Sanofi’s have fallen nearly 10%. Pfizer’s shares rose just under 1% in New York trading.

Officials of closely held Boehringer said in an email they were pleased with the high court’s ruling and maintain there is “is no reliable scientific evidence that Zantac can cause cancer.”

Representatives of GSK, Pfizer and Sanofi didn’t immediately respond to requests for comment on the ruling.

Another Look

The drugmakers challenged a decision by Medinilla, who found the plaintiff’s expert witnesses appropriately reviewed evidence about whether Zantac can cause cancer. The state’s highest court sent the cases back to the trial court for a judge to take another look at the expert testimony. Medinilla stepped down in February.

While judges in other states including California and Illinois had signed off on similar expert testimony, the drugmakers said Medinilla should have followed the lead of a federal judge in Florida, who in 2022 rejected the cancer evidence as unreliable. The justices in Delaware said the state’s laws governing expert testimony “are consistent with federal law” when it comes to weighing the legitimacy of scientific evidence.

The court noted Medinilla erred in deferring to jurors about the legitimacy of expert testimony and wrongfully applied a standard that “favored or presumed” the admissibility of expert testimony. She also ran afoul of the proper standard to evaluate the experts’ testimonies on so-called general causation — evidence that Zantac can transform into a carcinogen and sicken users under certain circumstances.

Ex-Zantac users have sued branded and generic drugmakers that made the heartburn medicine alleging the product caused 10 types of cancer, including breast, stomach and colon cancer. Plaintiffs contend the companies knew ranitidine — the drug’s active ingredient — turned into the potential carcinogen NDMA if not kept cool. In 2020, the US Food and Drug Administration asked companies to remove all ranitidine-based products.

National Attention

The case has drawn national attention since the focus of the litigation shifted to Delaware, after the Florida judge’s ruling undercut thousands of federal suits before her. Medinilla allowed the companies to file an early appeal of her ruling on the expert-witness testimony.

The US Chamber of Commerce filed a so-called “friend of the court” brief, arguing Medinilla erred by blessing expert-witness testimony in the Zantac cases “that was fundamentally unreliable.” The judge concluded rather than excluding expert witnesses, their evidence could be properly challenged by the companies via cross-examination.

Because the state’s highest court sent the cases back to the trial court for another look, there’s a chance they may still proceed to trial, said Mikal Watts, one of the plaintiffs’ lawyers who filed suit in Delaware.

“We believe that upon re-briefing under this new standard — with the science that now exists explaining why Zantac is still illegal to sell anywhere in the world six years after the FDA banned it — we can easily meet the new standard set forth by the Delaware Supreme Court today,” Watts said in an email.

The case is IN RE Zantac Litigation, No. 255, 2024, Delaware Supreme Court (Dover).

Top photo: Zantac. (Drew Angerer/Getty Images)