Yahoo TV

STORY: Four major drugmakers have been spared thousands of U.S. lawsuits.

A judge on Tuesday (December 6) found claims that the heartburn drug Zantac caused cancer were not supported by sound science.

The ruling knocked out 50,000 claims in federal court for GSK, Pfizer, Sanofi and Boehringer Ingelheim.

Lawyers for the plaintiffs said they were 'extremely surprised' by what they called a 'miscarriage of justice'.

They also 'fully expect' the ruling will be reversed on appeal.

A spokesperson for GSK said the company welcomed the decision, while Pfizer said it was pleased by the outcome.

All the drugmakers involved have denied Zantac causes cancer.

The drug was first approved in 1983 and became one of the first to hit $1 billion in annual sales.

It was originally marketed by a forerunner of GSK, and later sold to Pfizer, Boehringer Ingelheim and Sanofi.

But some manufacturers and pharmacies stopped sales of the drug in 2019.

That was due to concerns its active ingredient, ranitidine, degraded over time to form a chemical called NDMA - which is known to cause cancer in larger amounts.

The U.S. Food and Drug Administration in 2020 pulled all remaining brand name Zantac and generic versions off the market.

Lawsuits followed soon after the recalls began from people who said they developed cancer after taking Zantac.

On Tuesday, though, a Florida judge found that expert witnesses the plaintiffs planned to use could not be admitted in court.

She argued they used "unreliable methodologies".

The ruling does not directly affect tens of thousands of similar cases pending in state courts around the U.S.

The first state trial is currently scheduled to begin in February in California.

Shares in the drugmakers soared on Wednesday (December 7).

GSK was up over 8% in early trade, while Sanofi jumped 5%.