WASHINGTON (Reuters) – French drug maker Sanofi-Aventis and U.S. regulators are discussing potential revisions to prescribing instructions on antibiotic Ketek after safety reviewers said a strong warning may be needed about cases of liver failure, the Food and Drug Administration said on Friday.
The company and the FDA confirmed the talks after the Wall Street Journal cited an internal FDA report linking Ketek to 12 cases of liver failure, including four deaths.
FDA spokeswoman Susan Bro said the report was a confidential memo from reviewers in the FDA’s Office of Drug Safety and the agency would not release it publicly.
But she confirmed that the report called for new information on Ketek’s label about liver injury reports. One possibility the reviewers raised was adding a “black box,” the strongest warning possible for a prescription drug, Bro said.
The report “recommends labeling revisions be considered but not product withdrawal,” Bro said.
Bro said she could not say how many reports of liver damage in Ketek patients had been received because data were still being reviewed.
Ketek, which was approved in 2004 to treat respiratory infections, drew renewed scrutiny in January when researchers reported that three patients using the drug developed severe liver damage and one died.
The FDA had rejected the drug in 2001 and 2003, asking for more safety information.
U.S. lawmakers have questioned the FDA’s approval of the drug amid charges of faulty data from one of the company’s studies.
The safety reviewers noted that “while the numerical risk appears higher in the Ketek database, they are not able to conclude greater risk for liver injury in patients receiving Ketek than other drugs in the category,” Bro said.
“This will be carefully considered along with all other sources of expert review in the agency’s assessment of Ketek’s safety profile,” she added.
A Sanofi spokesman in Paris said the company “continues to believe that Ketek is safe and effective.”
“We are in talks with the FDA to evaluate secondary effects on the liver and as we are in discussions we are not going to start commenting on these figures,” the spokesman added, when asked about the alleged cases.
He said all secondary effects were reported to the FDA and talks on labeling had been going on for several months. He said the company did not have a copy of the safety reviewers’ memo.
Sanofi shares fell 24 cents, or 0.5 percent, to $46.67 in afternoon trading on the New York Stock Exchange.
(Additional reporting by Noelle Mennella in Paris and Kenneth Li in New York)
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