US biotech group Celgene Corp (NASDAQ:CELG) has made a US$7.2bn takeover approach to rival Receptos, although an analyst said it could face a bid battle.
Celgene offered US$232 a share for Receptos, which has an experimental pill treatment for bowel disease and relapsing multiple sclerosis known as Ozanimod.
Celgene said the deal would give it a transformational chance to develop treatments for several therapeutic areas.
Both companies' boards approved the deal, which values Receptos at a 12% premium to its July 14 closing price of US$207.18.
The tender is expected to close in the third quarter and the acquisition by the end of the year.
Celgene shares rose to nearly US$123 a share while Receptos' stock lifted to just over US$207 per share.
But other pharmaceutical firms such as the UK's AstraZeneca (LON:AZN), Israeli group Teva (TLV:TEVA) and Gilead Sciences (NASDAQ:GILD) of the US are also believed to have been interested in Receptos.
One broker, Cowen & Co, said Celgene appeared to have got a good deal and had not overpaid.
Another US broker, Wedbush, has an 'outperform' and US$348 acquisition value on Receptos, based on sales of Ozanimod and other drugs. That would value it at about US$10.9bn.
Wedbush analyst Liana Moussatos said the proposed acquisition price of US$7.2bn was only slightly more than one times Receptos's peak sales.
"Consequently, based on our valuation for Receptos, we believe another bidder may come in as we see plenty of potential upside to justify it," Moussatos said in a note.