Mylan, maker of the EpiPen, may have overcharged Medicaid as much as $1.27 billion over the past 10 years, The Hill reports.

According to a report by the Office of Inspector General, Mylan misclassified the emergency allergy treatment as a generic drug, which allowed the company to avoid steep price cuts required of brand-name drugs.

Mylan then ignored federal regulators when they informed the company of the misclassification, the OIG report said.

Mylan is believed to have reached a $465 million settlement with the Department of Justice, The Hill reports, though the DOJ has declined to confirm it.

Mylan raised the ire of the public last year when it raised the cost of the EpiPen from $100 for a two-pack dose to $600. The drug is used to save the lives of people with severe allergic reactions.

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