FILE PHOTO: French doctor Irene Frachon shows a box of Mediator to the media during the trial in the Mediator drug case at Nanterre courthouse near Paris May 14, 2012. REUTERS/Charles Platiau

PARIS (Reuters) - Drug maker Servier and the French drug regulator will face trial over weight-loss pill Mediator, believed to have caused at least 500 deaths in one of France’s worst health scandals, the prosecutor’s office said on Tuesday.

Once licensed as a diabetes treatment, the drug was widely prescribed as an appetite suppressant to help people lose weight.

Mediator, whose active chemical substance is known as Benfluorex, was withdrawn from the French market in 2009, around a decade after being pulled in Spain, Italy and the United States.

The prosecutor’s indictment covers charges of misleading claims as well as manslaughter and targets 14 people as well as 11 institutions including Servier and the French drug regulator ANSM.

According to the health ministry, at least 500 people died of heart valve trouble in France because of exposure to Mediator’s active ingredient. Other estimates based on extrapolations have put the death toll closer to 2,000.