June 5 (Reuters) - A federal judge asked the Food and Drug Administration (FDA) to reexamine its decision to reject citizen calls to restrict the use of antibiotics in animal feed, court filings showed.
The latest ruling is the second such setback for the FDA over concerns that overuse of antibiotics in animal feed is endangering human health by creating antibiotic-resistant "superbugs".
In March, a federal court ordered the FDA to begin proceedings to withdraw approval for the use of penicillin and tetracyclines in animal feed unless makers of the drugs can produce evidence that their use is safe.
The lawsuit was filed by environmental and public-health groups including The Natural Resources Defense Council, Center for Science in the Public Interest and the Union of Concerned Scientists in the Manhattan federal court.
The plaintiffs argued that using common antibiotics in livestock feed has contributed to the rapid growth of antibiotic-resistant bacteria in both animals and humans.
Two citizen petitions were filed by the plaintiffs in 1999 and 2005 requesting the FDA to begin withdrawal proceedings for all non-therapeutic uses of medically important antibiotics food producing animals.
In response, FDA rejected those two petitions citing the time and expense required to evaluate individual drug safety and to hold formal withdrawal proceedings, if necessary.
However, on Monday, U.S. Magistrate Judge Theodore Katz said: "Denying the petitions on the grounds that it would be too time consuming and resource-intensive to evaluate each individual drug's safety, and withdraw approval if a drug was not shown to be safe, is arbitrary and capricious."
Antibiotic-resistant infections cost Americans more than $20 billion each year, the plaintiffs said, citing a 2009 study from the Alliance for the Prudent Use of Antibiotics and Cook County Hospital.
The case is Natural Resources Defense Council et al. v. FDA, in the U.S. District Court for the Southern District of New York, no. 11-3562. (Reporting by Sakthi Prasad; Editing by David Cowell)