Sanofi, GlaxoSmithKline disclose DOJ investigation into Zantac after recalls

After global recalls of heartburn medicine Zantac and an FDA ban, the Department of Justice is investigating Sanofi and GlaxoSmithKline for possible violations of the False Claims Act. 

The drugmakers last year pulled their Zantac products over an impurity believed to cause cancer, and Sanofi said the probe is over disclosures relating to that impurity. GSK didn't comment on the nature of the investigation, but a spokesman said the company is cooperating.

A Sanofi spokeswoman said the company stands "by the long-standing science that supports the safety of Zantac OTC products, which have been used by consumers for over two decades." She declined to comment on "specifics of ongoing litigation."

RELATED: Sanofi takes $186M hit on the heels of Zantac recall 

Sanofi last year took a $186 million write-down on the product after an October recall. GlaxoSmithKline, the drug’s original developer, sold the branded version in the U.K. and elsewhere before its recall.

Both companies recalled their Zantac products after the discovery of an impurity called N-nitrosodimethylamine, which is believed to cause cancer. 

The saga is part of a yearslong investigation by the FDA and other regulators into drug impurities that might cause cancer, starting in 2018 with heart medicines valsartan and losartan. Global Zantac recalls gained steam last year and into this year. In April, the FDA forcibly removed the drug and its generics from the U.S. market. 

Last September, an online pharmacy and testing lab called Valisure filed an FDA citizen petition notifying the agency that it found the impurity in heartburn meds. Another lab in January alerted the agency to its own discovery, and the FDA later confirmed the findings.

RELATED: GSK joins other drugmakers recalling Zantac products    

Aside from the Department of Justice probes, both Sanofi and GlaxoSmithKline disclosed a Zantac-related lawsuit from the New Mexico Attorney General. That suit alleges violations of the state’s unfair practices act, false advertising, public nuisance and negligence.

Both companies said they couldn’t estimate the potential financial implications of the lawsuits.