Radium-223 dichloride, which Bayer used to call Alpharadin, is designed to target bone metastases from prostate cancer that cannot be treated by standard hormone therapy.
Bayer licensed radium-223 from Algeta in 2009, and if approved in the United States, radium-223 will be co-promoted by Bayer and Algeta, the Oslo-based company said on Friday.
Bayer, which on Wednesday said it was requesting EU approval for the drug, will market radium-223 alone in Europe if the treatment is approved there.
Bayer said last year that Radium-223 dichloride could become a "blockbuster" product with annual sales of least 1 billion euros.
The drug has some properties of calcium, which makes it cling to cancerous bone cells and then destroy them via alpha rays, which is more targeted that the shotgun approach of conventional radiotherapy.
(Reporting by Jonathan Gould; Editing by Hans-Juergen Peters)