GSK has seen nearly £7bn wiped off its value after a US court ruled that over 70,000 lawsuits against the British pharmaceutical company could proceed.
The news led to GSK’s largest share price drop in almost two years as it now faces trials to determine whether its former heartburn medication, Zantac, causes cancer.
In a ruling on Friday, made public over the weekend, Judge Vivian Medinil stated that a jury should consider the scientific evidence from both sides. She affirmed that scientific evidence linking Zantac to cancer is admissible in court, adding, “In Delaware… trial courts entrust questions of science to the scientists. It would be improper to simply dismiss these experts as ‘poseurs or witnesses for hire’.”
This development follows years of legal disputes over Zantac, which was withdrawn from sale by drugmakers in 2019 after US regulators found “unacceptable levels” of probable cancer-causing ingredients. Zantac had been available over the counter in the US, while in the UK, GSK recalled four prescription-only Zantac products.
GSK and other companies that sold Zantac have been contesting these lawsuits since mid-2022, denying claims that Zantac’s ingredients cause cancer.
Some court cases have ruled in their favour, including a jury in Chicago last month that found Zantac did not cause an individual to develop colon cancer. Additionally, GSK reached out-of-court settlements in California last October.
