French pharma firm Servier and the country's medicine safety agency ANSM are facing accusations of involuntary manslaughter and fraud in a major trial that opened Monday over a diabetes medication suspected of causing hundreds of deaths.

At least 500 people are thought to have died after taking the drug, Mediator, which was also prescribed as a weight-loss medication until being taken off the market in 2009. Mediator was used by an estimated 5 million people since 1976, and ANSM says as many as one in 2,000 patients may have needed hospital treatment for side effects of the drug.

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Almost 5,000 victims have been identified, 2,684 of whom will be represented at the trial by some 376 lawyers. Experts say as many as 2,100 people may die in the long term from side effects of the drug, which has been linked to heart-valve problems and a rare lung disease.

'Endless denial of responsibility'

The scandal surrounding Mediator was the subject of a 2016 French movie, "150 Milligrams," which is based on the work of the lung doctor Irene Frachon, who played a major role in uncovering the alleged wrongdoing by Servier. Frachon, who on Monday slammed Servier for its "endless denial of responsibility," is set be one of about 100 witnesses to testify at the trial.

According to lawyer Charles Joseph-Oudin, Servier "had deliberately lied and hidden the drug's dangerous properties" for "profit."

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But the pharma company says it was unaware of the risks before 2009, even though the drug had by then already been banned in the United States, Spain and Italy.

The ANSM is facing charges for alleged negligence and tardiness in suspending the drug.

The accused risk a fine or an order to compensate victims.

Servier, which is based in a Paris suburb, employs 22,000 people worldwide and reached a turnover of €4.1 billion ($4.5 billion) last year.

tj/rc (dpa, AFP, AP)

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