Biogen Idec has gone back to the future by dropping Idec from its name.

The Cambridge, Mass.-based biotechnology company announced Monday that it is now simply Biogen – which was its name prior to the 2003 merger with San Diego, Calif.-based Idec Pharmaceuticals.

“The old Biogen and the old IDEC each contributed meaningfully to our current success, but today we are a new company, distinct from either parent, and we hope not only to carry on our heritage of excellence, but to forge new ground,” CEO George Scangos wrote on the company’s website. “Our name is intended to acknowledge our heritage but also to create a new image to reflect our new reality.”

Founded in 1978, Biogen has more than 1,300 employees in the Triangle and is in the midst of adding more than 100 new employees locally. It produces a half-dozen of its multiple sclerosis and hemophilia drugs in the Triangle.

IDEC brought two cancer treatments to the combined business at the time of the merger. But in 2010 the company decided to shift away from oncology to focus on three therapeutic areas: neurology, immunology and hematology.

The new name comes with a new logo and new signage at the company’s two Research Triangle Park campuses. But the company’s stock will continue to trade on Nasdaq under the symbol “BIIB.”

Biogen’s stock rose 10 percent Friday in the wake of encouraging test results for the company’s experimental drug for the treatment of Alzheimer’s disease, aducanumab.

Some of the clinical work on aducanumab is being performed in RTP, but the company hasn’t decided where it would be manufactured if it wins approval, said company spokesman Steven Goldsmith.