PARIS (AP) — A massive trial with more than 4,000 plaintiffs is opening for French pharmaceutical giant Servier Laboratoires and France's medicines watchdog, accused of involuntary manslaughter, fraud and other charges in a scandal over a diabetes medication suspected of causing hundreds of deaths.

Although designed as a diabetes drug, Mediator was widely prescribed as a hunger suppressant to millions of people before sales were suspended in France in 2009. The trial opening Monday in Paris is expected to last six months.

A 2010 study said the drug was suspected in 1,000-2,000 deaths, with doctors linking it to heart and lung problems.

François de Castro, a lawyer for Servier, said the pharmaceutical firm wasn't aware of risks associated with Mediator before 2009 — 33 years after it first went on sale.