GSK, Pfizer, Sanofi Escape U.S. Federal Litigation Over Zantac

Drugmakers GSK Plc, Pfizer Inc, Sanofi SA and Boehringer Ingelheim on Tuesday defeated thousands of U.S. lawsuits claiming that the heartburn drug Zantac caused cancer, as a judge found the claims were not backed by sound science.

The ruling by U.S. District Judge Robin Rosenberg in West Palm Beach, Florida, knocks out about 50,000 claims in federal court, though it does not affect tens of thousands of similar cases pending in state courts around the country.

"We are extremely surprised by this miscarriage of justice and fully expect that the Eleventh Circuit Court of Appeal will reverse these rulings on appeal," lawyers for the plaintiffs said in a joint statement.

A Sanofi spokesperson said the decision "significantly decreases the scope of the litigation potentially by over 50%."

A spokesperson for GSK said the company welcomed the decision, while Pfizer and Boehringer Ingelheim did not immediately respond to requests for comment. All the drugmakers have denied that Zantac causes cancer.

Zantac, first approved in 1983, became the world's best selling medicine in 1988 and one of the first-ever drugs to top $1 billion in annual sales. Originally marketed by a forerunner of GSK, it was later sold successively to Pfizer, Boehringer Ingelheim and finally Sanofi.

Numerous generic drugmakers also launched versions of the medicine, but are not part of the federal mass tort litigation.

In 2019, some manufacturers and pharmacies halted sales of the drug over concerns that its active ingredient, ranitidine, degraded over time to form a chemical called NDMA. While NDMA is found in low levels in food and water, it is known to cause cancer in larger amounts.

The U.S. Food and Drug Administration in 2020 pulled all remaining brand name and generic Zantac products off the market, citing research showing the amount of NDMA in the products increases the longer the drug is stored and could potentially become unsafe.

Lawsuits began piling up soon after the recalls began from people who said they developed cancer after taking Zantac. Plaintiffs said that the companies knew, or should have known, that ranitidine posed a cancer risk and that they failed to warn consumers.

All of the cases filed in federal courts nationwide were consolidated before Rosenberg in Florida.

In Tuesday's order, she found that expert witnesses the plaintiffs planned to use to establish that Zantac can cause cancer could not be admitted in court because they "systemically utilized unreliable methodologies" and showed "a lack of internally consistent, objective, science-based standards for the evenhanded evaluation of data."