Biogen Idec, a biotech firm based in Cambridge, Massachusetts, has bought the rights of two experimental therapies for Alzheimer's from Tokyo-based Eisai Co, Bloomberg reported. 

With the rights purchase, Biogen Idec Inc would be able to add to its portfolio of therapies targeted at brain disorders. Biogen is a developer, maker and seller of neurology, oncology and immunology-focused drugs. Among the conditions addressed by the company's drugs are multiple sclerosis, rheumatoid arthritis, non-Hodgkin's lymphoma, psoriasis and Crohn's disease, Bloomberg information showed.

In a statement, the two firms said an upfront payment will be given to Eisai by Biogen. When the drugs, currently called E2609 and BAN2401, will be approved and brought to market, Eisai will also be getting fixed development and milestone amounts. Both drug manufacturers will be splitting the development costs. The statement, however, did not specify how much these financial amounts will be, the report said.

Biogen Chief Executive Officer George Scangos said in the statement, "Eisai's candidates have demonstrated compelling early data and complement our Alzheimer's disease research while extending our pipeline in this critical area." He called the partnership with the Japanese firm a "natural fit," the report said.

The statement also revealed that Eisai will be spearheading the development of the therapies and will take care of obtaining approvals for the drugs from the authorities. The Tokyo-based firm made Aricept, the world's best-selling Alzheimer's therapy, which lost patent protection in 2010. Eisai will also get revenue from the two drugs, with both firms dividing the profits between themselves. On its end, Biogen will help endorse the two medicines in the US, European and other markets, the report said.

In addition, the deal between the two drugmakers also gave Eisai the option to develop together and sell two experimental antibodies from Biogen for Alzheimer's, the report said.