A bidding war for Shire is threatening to break out after Botox maker Allergan said it was considering a takeover offer for the rare diseases drug maker.
Shares in the London-listed firm jumped 9% after Reuters had reported Allergan’s interest.
Earlier on Thursday, Japan’s Takeda said it was in talks with Shire after making a £43bn bid.
Shire rejected the £46.50 a share offer that Takeda made on 12 April. However, both firms said talks were continuing.
Shire said that Takeda had made three approaches, with the first worth £41bn on 29 March.
The most recent offer was worth £43bn and would result in Shire shareholders owning about half the enlarged group.
That offer was rejected by Shire’s board as directors said it “significantly undervalued the company, its growth prospects and pipeline”.
After making modest gains following confirmation of Takeda’s interest, Shire shares ended the day £2.21 higher at £39.75.
The shares had been trading at about £31 a month ago before Takeda said in late March it was considering an offer for the Irish firm.
Takeda said it would only make a firm offer with the backing of Shire’s board and following satisfactory due diligence.
The Japanese firm is interested in a Shire takeover to strengthen its cancer, stomach and brain drug portfolio.
This week Shire said it was selling its cancer treatment unit to France’s Servier for £1.7bn in a deal that was initiated in December and was unrelated to the possibility of a takeover bid.
Shire was founded in the UK and still has a large base in Basingstoke, but moved its corporate headquarters to Dublin a decade ago. It has 24,000 employees in 65 countries.
According to the company, there are 7,000 rare diseases, but fewer than 5% have a treatment. Most are genetic and about half begin in childhood.