Biogen Idec's controversial multiple sclerosis (MS) drug Tysabri will now be available in Europe for serious cases of the disease, the company announced.

European Union (EU) authorities have approved marketing of Tysabri as a treatment for relapsing remitting MS patients for the purpose of delaying the progress of disability and reduction of the frequency of relapses, the company said.

While this will be the drug's first appearance in Europe, it has a colorful history in the U.S. In February 2005, the FDA recalled Tysabri after clinical trials revealed three patients had contracted a brain disease known as progressive multifocal leukocephalopathy (PML). Two of the patients died.

After further consideration, the FDA allowed Tysabri's to return to the market in a restricted distribution program after it deemed that the advantages of the drug for MS patients in critical condition outweighed the low probability of new cases of PML.

In its EU approval submission, Biogen Idec stated that its risk management plan for Tysabri includes ways to minimize the potential risk of PML and other infections.