By Ian Walker

LONDON--Shire PLC (SHP.LN) confirmed Friday that it has rejected an offer proposal from AbbVie Inc. (ABBV), saying it "fundamentally undervalued Shire and its prospects as a leader in Rare Diseases and Specialty Markets."

The U.K.-listed drug maker added that it expects to more than double its 2013 annual product sales to $10 billion by 2020.

Shire, which was responding to an earlier announcement by AbbVie, said it received a third offer proposal from AbbVie, which was spun off from Abbott Laboratories in early 2013, on May 30 which valued it at 46.11 pounds ($78.24) a share.

The proposal comprised GBP20.44 in cash and 0.7988 AbbVie shares per Shire share and involved a new U.S. listed holding company with a U.K. tax domicile.

"The Board believes the proposal fundamentally undervalued Shire and its prospects and that as an independent company Shire's focused growth strategy will continue to deliver significant shareholder value and patient benefits," Shire Chairwoman Susan Kilsby said

Shire shares in London at 0750 GMT up 4.52 pence, or 12%, at 4190 pence in a higher FTSE 100 Index--up 0.28%.

Write to Ian Walker at

(END) Dow Jones Newswires

June 20, 2014 04:20 ET (08:20 GMT)

Copyright (c) 2014 Dow Jones & Company, Inc.