The online pharmacy that first detected a potentially cancer-causing chemical in branded and generic versions of Zantac had sharp words for the U.S. Food & Drug Administration (FDA) late last week, after the agency said its own testing suggested ranitidine did not create the carcinogen after ingestion.
In a statement to Reuters, Valisure CEO David Light criticized the FDA’s testing methods “as overly simplistic conditions that do not properly evaluate a real-world stomach.” He and his company continued to urge the agency tor order a Zantac recall.
Valisure formally petitioned the FDA for a recall in September, after detecting N-nitrosodimethylamine (NDMA) in every batch of Zantac and ranitidine it tested, and often at levels that far exceeded the agency’s recommended daily limits. According to Valisure, some of its testing also suggested the presence of NDMA resulted from the instability of the ranitidine molecule, which degrades when subjected to conditions similar to digestion.
The U.S. Environmental Protection Agency considers NDMA a probable human carcinogen. Animal tests have linked the chemical to cancer, including kidney, liver, and gastrointestinal tumors.
The FDA notified the public of Valisure’s findings on September 13, but did not recall any Zantac or ranitidine products.
Last Friday, the FDA announced that its own tests simulating conditions of the human stomach and small intestines suggested ranitidine did not form NDMA after ingestion. Janet Woodcock, director of the agency’s Center for Drug Evaluation and Research added that the levels of NDMA detected in the drug itself were “similar to the levels you would expect to be exposed to if you ate common foods like grilled or smoked meats.”
Yet according to Reuters, the FDA’s own published results show that some over-the-counter Zantac and ranitidine products had as much as nine-times the agency’s acceptable limit of NDMA. What’s more, the testing isn’t even complete, with the agency acknowledging plans for future human tests to fully understand whether the chemical forms after ingestion.
Dozens of countries have either banned, recalled or suspended the sale of Zantac and ranitidine products since September.
While the FDA hasn’t ordered a Zantac recall in the United States, several companies, including Sanofi-Aventis, Sandoz, and Dr. Reddy’s Laboratories, among others, have chosen to voluntarily recall their ranitidine products. A number of retailers, including Walgreens, Walmart, and CVS, have also pulled the medications from store shelves.