The logo of pharmaceutical company GlaxoSmithKline is seen at its facility in Stevenage, Britain, October 26, 2020.
Mateo children | Reuters
LONDON — Shares of the British pharmaceutical giant GSK fell 9% on Monday, after a US court ruled that scientific evidence could be presented in a series of lawsuits related to the discontinued heartburn drug Zantac.
The Delaware State Court ruled Friday night that plaintiffs' experts could testify in the roughly 75,000 cases alleging that the once-popular drug ranitidine, sold under the brand name Zantac in the United States, can cause cancer.
“This case has always been about putting science before a jury,” Brent Wisner, an attorney with the Wisner Baum firm who represents many of the plaintiffs, said in a statement.
The conflict has been going on for years and involves numerous pharmaceutical companies. Zantac was sold by GSK as a prescription drug in the 1980s before becoming an over-the-counter drug after its patent expired in the late 1990s; owners included GSK, the French sanafithe American firm Pfizer and the German Boehringer Ingelheim.
The drug was withdrawn from the European and US markets in 2019 and 2020 after regulators conducted a safety review that raised concerns that it contained a probable carcinogen called NDMA.
The companies involved deny that there is a scientific consensus that the drug may be related to the subsequent development of cancers.
In a statement on Friday, GSK said it disagreed with Delaware's latest ruling and would immediately seek an appeal.
He said the decision contradicted the federal court's December 2022 multidistrict litigation ruling, which dismissed all cases alleging five types of cancer. He added that the court's decision only concerned whether the methodology used by the plaintiffs' experts was reliable enough to be introduced as evidence at trial.
“Following 16 epidemiological studies analyzing human data on ranitidine use, the scientific consensus is that there is no consistent or reliable evidence that ranitidine increases the risk of cancer,” GSK said.
Sanofi, which is named in about 25,000 of the 75,000 cases, said in its own statement Friday that it was disappointed with the decision not to exclude the plaintiffs' experts from the cases and would also appeal. Sanofi shares fell 1% on Monday.
CNBC has contacted Pfizer and Boehringer Ingelheim for comment. Last month, the Financial Times reported that Pfizer agreed to pay between $200 million and $250 million to settle more than 10,000 Zantac lawsuits in Delaware. CNBC has not independently confirmed the amount.
Jefferies analysts had flagged a potential tailwind for GSK in late May after an Illinois jury found GSK and Boehringer Ingelheim were not responsible for colorectal cancer in the first Zantac case to go to trial.
