ROCKVILLE, Md. (AP) -- Biotech drug developer Human Genome Sciences Inc. has rejected an unsolicited $2.59 billion takeover offer from GlaxoSmithKline PLC, saying it undervalues the company.
But the Rockville, Md., company said Thursday that it has decided to explore its strategic options, which could include a potential sale of the company. It invited GlaxoSmithKline to participate in its exploratory process.
GlaxoSmithKline offered $13 per share, which is an 81 percent premium to Human Genome's closing price on Wednesday of $7.17 per share. Human Genome currently has about 199.1 million outstanding shares, according to FactSet.
Shares of Human Genome Sciences jumped $6.73, or 93.9 percent, to $13.90 in premarket trading, while GlaxoSmithKline's stock added 71 cents to $47.08.
GlaxoSmithKline is Human Genome's partner on the lupus drug Benlysta. Speculation has swirled since October that GlaxoSmithKline may try to buy Human Genome.
Human Genome said Thursday that it has asked for more information from Glaxo, which is based in the United Kingdom, on products that are in its clinical pipeline. Human Genome has substantial financial rights in some of those products.