A federal appeals court has revived a multibillion-dollar Medicare fraud case brought by whistle-blowers alleging Johnson & Johnson paid doctors kickbacks to wrongly prescribe an expensive drug.

Two former salespeople for the health care giant allege J&J illegally marketed its blockbuster anemia drug Procrit. They claim the company got doctors to prescribe it for unapproved uses and sometimes at high doses that could be dangerous.

Federal regulators have since put restrictions on which patients can get the drug and how much they can take, hurting Procrit sales.

A federal appeals court in Boston has revived the case and sent it back to the District Court in Boston.

Johnson & Johnson officials say they will comment later today.