What GSK Didn’t Say About Zantac for 40 Years

Hi, it’s Anna in Virginia. I’m going to tell you a tale about a pharmaceutical company that sold a potentially dangerous drug and what it knew 40 years ago that may have saved lives, but first…

The heartburn tablet Zantac was on the market for almost 40 years. As drugs go, it was a raging success. It raked in billions in sales for its creator, a company that now goes by GSK.

All the while GSK, just Glaxo back then, had a 10-page report from 1982 somewhere in its files outlining an experiment that found Zantac’s active ingredient, ranitidine, under certain conditions could form a probable carcinogen called NDMA. Glaxo executives in the UK didn’t share this with their American counterparts in the US as they gunned for Food and Drug Administration approval in the early 1980s. They also didn’t share it with the FDA.

So, how do I know about it, you ask? My colleagues Susan Berfield, Jef Feeley and I got access to thousands of pages of court documents, including depositions and studies that have never been made public before, as well as drug applications and meeting transcripts at the FDA to trace Zantac’s hidden history.

Read our story here.

The 10-page report, now known as the Tanner study, wasn’t the only sign something might be wrong with the pills. Throughout the years, GSK downplayed signs Zantac could degrade before its expiration date was up — which was a recipe for impurities, potentially harmful ones, to form. But it wasn’t GSK, or even the FDA, that initially revealed the problems with Zantac, and a number of generic competitors. It was an independent lab called Valisure that does drug testing. It found the NDMA in 2019 and alerted the FDA that scientists at the lab believed the problem was the ranitidine itself. It was degrading to create NDMA. Only then did the recalls start.

The FDA conducted its own research and eventually forced Zantac off the market in 2020. But that isn’t the end.

More than 70,000 lawsuits have been filed in state courts against the company by people who took Zantac and generic versions of it. The first one to go to trial, set in the California Superior Court in Alameda County, may start as early as this month.

The real kicker for me is that the pharmaceutical company Sanofi, which now owns the rights to sell Zantac in the US, has found an odd way to bring the pills back to drugstore shelves. The drugmaker first attempted to see if it could somehow safely continue to use ranitidine in Zantac, but that didn’t work.

So instead, Sanofi began selling non-prescription Zantac in 2021 that doesn’t contain any of the key ingredient that defined the drug. It’s instead now made with famotidine, the active ingredient in competitor Pepcid. So if your local Walgreens happens to run out of Pepcid, now you know where to find a secret stash, just grab a box of Zantac. — Anna Edney