The FDA announced Wednesday that Zoetis ($ZTS) has agreed to withdraw the arsenic-based drug Histostat (nitarsone) from the market by this fall. The move follows years of pressure from food safety groups concerned that the drug--used to prevent blackhead disease in poultry--could endanger human health.
According to a statement from the FDA, published reports suggest that the organic form of arsenic contained in drugs like Histostat can transform into inorganic arsenic, which is a known carcinogen. In fact, in 2011, Zoetis' former owner, Pfizer ($PFE), agreed to cease marketing of its arsenic-based poultry drug 3-Nitro (roxarsone) after the FDA found increased levels of inorganic arsenic in chickens. Subsequent FDA studies have affirmed the 2011 findings, the FDA said.
In 2013, the FDA withdrew the approvals of 98 arsenic-based animal drugs in response to a petition filed by the Center for Food Safety and other groups.
But Zoetis continued to hold three separate FDA approvals for Histostat, which remained on the market. And despite its authorized use as a preventative, advocacy groups such as the Center for Food Safety alleged that farmers were adding the drug to poultry feed to spur faster weight gain and give chickens and turkeys a healthy-looking color.
"The withdrawal of these harmful feed additives is a major victory for consumers and the health of our food system," said Paige Tomaselli, senior attorney with the Center for Food Safety, in a statement. "It is unfortunate that it took over 5 years of intense pressure from outside groups, yet in the end, we are pleased that FDA listened to our scientific objections and is now ridding arsenic from our meat supply."
Zoetis plans to phase out Histostat gradually this year, according to a letter to the FDA sent by Catherine Knupp, president of veterinary medicine research and development at the company. That timeline "provides the turkey industry with time (one season of the disease) to prepare for a future in which no therapeutic product will be available," she wrote.