KEY POINTS
  • Bloomberg reports that Alexion Pharmaceuticals is being investigated by the inspector general of the Department of Health and Human Services.
  • The focus of the investigation was not disclosed, Bloomberg reports.
  • The news sent the stock to session lows.

Shares of Alexion Pharmaceuticals fell after Bloomberg reported that the company is being investigated by the Department of Health and Human Services' inspector general.

The company later told CNBC that it is aware that the office is working with the Justice Department and the U.S. attorney for Massachusetts on a previously disclosed inquiry.