In 1978, Glaxo Laboratories developed a molecule called ranitidine, which could treat heartburn. Soon after the U.S. Food and Drug Administration (FDA) approved the drug under the brand name Zantac, ranitidine rapidly became the world’s top-selling prescription medication. From the beginning to the end, Glaxo was warned by independent investigators and scientists about Zantac’s potential cancer risks. Glaxo failed to share critical evaluations of the drug with the FDA and endorsed erroneous research intended to minimize safety concerns. The company launched an aggressive marketing campaign to promote Zantac as more effective, more convenient, and safer than the alternative drug Tagamet. With Americans already spending roughly a billion dollars annually for heartburn relief, Glaxo introduced a 75mg over-the-counter Zantac pill.
While considerable evidence and suspicions indicated Zantac’s cancer-causing properties, documents show Glaxo ignored the warnings. Connected to cancer as early as 1956, NDMA belongs to a group of chemicals called nitrosamines, which have caused cancer in every species of animal tested. A prominent pharmaceutical analyst suggested that under certain conditions in the stomach, a chemical reaction could turn ranitidine into NDMA. However, Glaxo’s board never requested any studies to determine if ranitidine could form into nitrosamine. Even after several independent studies revealed ranitidine resulted in toxic and mutagenic effects, Glaxo still tried to convince everyone of the safety of their drug. In 1982, despite the company’s scientist Richard Tanner finding up to 232,000 nanograms of NDMA in Zantac, court documents show that Glaxo kept this study a secret.
In 2019, Valisure, a private lab, sent the FDA a document regarding Zantac’s extremely high levels of NDMA. After finding NDMA in every version of ranitidine it analyzed, the lab determined the problem inherently existed with the molecule itself. Although consuming minuscule amounts of the carcinogen is not believed to be harmful, lab tests uncovered excessive amounts of NDMA in ranitidine. It takes less than a milligram of NDMA to mutate mice cells, and 2 grams is enough to kill a person. Consequently, the FDA forced all versions of the drug off the market in 2020. However, the FDA maintained that there were no consistent signals that the drug increased cancer risks. Critics believe the FDA’s stance was an attempt to absolve the agency of wrongdoing.