GSK notches another Zantac win as Florida court tosses expert testimony linking heartburn drug to cancer

After knocking out multiple personal injury lawsuits this summer, GSK has prevailed on another front in its long-running Zantac litigation.

Late Thursday, GSK said it came out on top in a Daubert ruling in Florida State Court, which has tossed experts’ general and specific causation testimony attempting to link ranitidine—previously the main ingredient in Zantac—to a plaintiff’s prostate cancer.

As a result, GSK will now seek dismissal of the Wilson case in Florida, in which plaintiffs have alleged a causal link between ranitidine and prostate cancer.

GSK likened the decision to a previous victory in 2019, when the judge overseeing the company’s federal multidistrict litigation around Zantac rejected all expert evidence put forward by plaintiffs and dismissed all multidistrict litigation cases claiming the once-popular heartburn drug caused patients to develop bladder, esophageal, gastric, liver or pancreatic cancers.

GSK has long argued that the science linking Zantac to cancer risks is unsound. In its latest release, the company noted that 16 epidemiological studies conducted since 2019 have found that there is “no consistent or reliable evidence that ranitidine increases the risk of any cancer.”

The so-called Daubert standard was established in the Supreme Court back in 1993 and provides criteria for determining whether expert testimony is admissible under a federal evidence rule, GSK explained.

“In applying the Daubert standard, the Court acts as a gatekeeper, ensuring that expert opinions meet certain standards for reliability and that speculative or unreliable opinions are not presented to the jury,” the company noted.

The favorable Daubert decision follows several recent developments in the Zantac litigation.

Earlier this month, the company said it had emerged victorious in Illinois state court after a jury determined that the company wasn’t liable for a plaintiff’s colorectal cancer.

That win closely followed a settlement in a separate Zantac prostate cancer lawsuit that had been pending in Illinois.

Furthermore, in the first Zantac personal injury case to go to trial, Chicago jurors in late May absolved GSK and Boehringer Ingelheim of fault on claims that Zantac had caused another plaintiff’s colon cancer.

The alleged link between Zantac and the possible carcinogen N-nitrosodimethylamine (NDMA) was first raised in 2019. In the wake of the safety flag, the FDA called for all versions of Zantac’s original formulation to be pulled from the U.S. market in April 2020.

The drug originally won approval in 1983 under GSK's ownership. Following the drug's loss of patent exclusivity in 1997, Pfizer, Sanofi, Boehringer Ingelheim and others began selling generic versions of Zantac.