GSK: Delaware Supreme Court agrees appeal over Zantac cancer case claim

Pharmaceutical giant GlaxoSmithKline (GSK) and rival drug manufacturers, including Sanofi, Pfizer and Boehringer Ingelheim, have won the right to an appeal hearing by the Delaware Supreme Court, regarding the now-discontinued antacid Zantac amid claims that an ingredient in it may cause cancer. There are now more than 70,000 lawsuits regarding the drug.

The appeal is against a lower court judge's earlier agreement to allow the plaintiffs to offer expert testimony on the alleged cancer link. The drug makers argued the testimony was not supported by sound scientific methods. 

The main concerns revolve around ranitidine, Zantac's active ingredient, which is believed to potentially degrade into N-nitrosodimethylamine (NDMA), a possible carcinogen, if the drug is stored at higher temperatures or left on shelves for a long time. 

However, GSK has consistently denied these claims, saying that the expert testimony on which these concerns were based was not reliable. 

The Food and Drug Administration (FDA) recalled Zantac in 2020, with Australia and the European Union also opting for voluntary recalls. 

Before the recalls, Zantac was sold by GSK, US pharma giant Pfizer, French drug company Sanofi and Boehringer Ingelheim, based in Germany.

GSK's shares were up more than 3% by Tuesday's market close on news of the appeal.  

GSK said in a press release on Tuesday: "GSK welcomes today's decision by the Delaware Supreme Court that it will review the Delaware Superior Court's decision allowing the introduction of plaintiffs' expert evidence at trial. 

"The scientific consensus remains that there is no consistent or reliable evidence that ranitidine increases the risk of any cancer. Since 2019, there are 16 epidemiological studies looking at