Fresenius Medical Care (NYSE:FMS; ETR:FRE) and NxStage Medical (NSDQ:NXTM) have received a request from the US Federal Trade Commission asking for more information on Fresenius’ $2 billion acquisition of NxStage, according to an SEC filing.

The companies originally announced the acquisition in August, with Fresenius looking to pay $30 per share for Lawrence, Mass.-based home hemodialysis developer NxStage.

The request from the FTC will extend the waiting period imposed by the HSR act until 30 days after the companies have complied with the request, though that period can be terminated earlier by the FTC, NxStage said in an SEC filing.

Fresenius said it plans to fund the deal with cash and debt and expects NxStage to add to net income and earnings per share within three years of the deal’s close.