Norway-based cancer drug maker Algeta ASA says it has received a preliminary takeover offer from Germany's Bayer AG that values the company at about $2.4 billion.

Algeta said in a statement Tuesday that the offer is for 336 kroner ($55.11) per share; the company has nearly 44 million shares. It said that discussions are at an early stage and the proposal "may or may not lead to a transaction."

Algeta's shares were up 30.3 percent in Oslo at 344.80 kroner after the announcement. Bayer's stock slipped 0.1 percent to 95.93 euros ($129.78) in Frankfurt trading.

Algeta has its headquarters in Oslo and has a U.S. subsidiary, Algeta US, LLC, based in Cambridge, Massachusetts.