PARSIPPANY, N.J. (AP) — Actavis announced that federal regulators have requested additional information related to its planned acquisition of fellow drugmaker Warner Chilcott PLC.

The $8.5 billion all-stock deal originally announced in May would create the third-biggest specialty pharmaceutical company in the U.S. market.

The Federal Trade Commission’s request extends the anti-trust waiting period related to the deal until 30 days after Actavis and Warner Chilcott have fully complied with the request, unless that period is extended voluntarily by the companies or terminated early by the FTC.

Parsippany, N.J.-based Actavis and Ireland’s Warner Chilcott said they plan to fully comply with the FTC’s review and still expect the deal to close in the second half of 2013.

Actavis shares closed at $124.07 on Wednesday.