"The way is now clear for the Bayer group to acquire Norwegian pharmaceutical company Algeta," the German giant said in a statement.
"On expiration of the offer deadline on February 26, Bayer had received acceptances for the voluntary takeover offer for a total of approximately 42.73 million shares, representing approximately 97.28 percent of Algeta's share capital," the statement said.
The German firm had offered Algeta shareholders 362 kronor per share in cash.
Bayer said it has obtained all regulatory approvals required for completion of the deal.
"The transfer of shares to Bayer and the payment of the offer price will take place in the coming days but no later than March 12," it said.
Following that, Bayer would initiate a compulsory acquisition process with the aim of becoming the sole shareholder of Algeta.
It would also file for delisting of the Algeta shares from the Oslo Stock Exchange.
Bayer said it expected to complete the acquisition in the first quarter of this year.
Bayer and Algeta have been collaborating since 2009 on the development and commercialisation of the cancer drug Xofigo.
"The acquisition gives us full control over Xofigo. We are absolutely convinced of the potential of this drug and the underlying technology to provide patients with innovative treatment options," Bayer said.