Genentech ( DNA) and Biogen ( BGEN) agreed to work together on the development of a BR3 protein therapeutic currently in Biogen's pipeline in a bid to find a treatment for autoimmune disorders.

Financial terms of the arrangement weren't disclosed. The protein is a B-cell activating factor receptor and is a key target for developing drugs to treat disorders associated with abnormal B-lymphocyte activity, such as rheumatoid arthritis and lupus.

Both companies will be collaborating on development efforts.

The protein, BAFF-R, was first identified by Biogen. It stimulates B-lymphocytes to develop into mature B-cells that produce antibodies, the body's first line of defense against infection.

In rheumatoid arthritis and other autoimmune diseases, higher levels contribute to the production of autoantibodies that attack and destroy the body's own tissue and organs.

Around midday, Genentech was gaining 2.6% to $76.56 on the New York Stock Exchange, and Biogen was down 1.8% to $47.25 on the Nasdaq.

Separately, Banc of America raised its price target on Genentech to $80, and Jefferies raised its target on the stock to $86.