Biogen Idec's stock was up 4 percent in early trading Thursday after federal regulators approved the company's multiple sclerosis drug Tecfidera.
The Food and Drug Administration's decision on Wednesday came just days after the European Union backed the drug, a new oral treatment for people with relapsing forms of MS.
Biogen Idec, which employs more than 1,000 people at its Research Triangle Park campus, also makes the multiple sclerosis drugs Avonex and Tysabri.
Tecfidera could generate $3.25 billion in annual revenue by 2017, according to Bloomberg News.

Officials with the N.C. Biotechnology Center are in discussions with at least 20 companies that are considering expansion in this state.
Biogen Idec is preparing to expand its Research Triangle Park campus, reinforcing the Massachusetts drug company's commitment to its operations in this region.
The new CEO of Biogen Idec, a Massachusetts company that employs more than 850 people at its campus in Research Triangle Park, is preparing a shake up of the company.
Biogen Idec, which employs about 850 people in Research Triangle Park, is seeking a new top executive.