Associated Press

CAMBRIDGE, Mass. — Biotechnology company (Nasdaq: BIIB) said Monday that its chief operating officer plans to retire at the end of the year.

The announcement comes as Biogen prepares to name a new CEO to replace James C. Mullen, 51, who is retiring effective Tuesday. Biogen said Monday that it will choose a successor in the next few weeks.

COO Robert A. Hamm, 58, plans to retire Dec. 31 after 16 years at Biogen, the company said.

Biogen has two significant operations in the Research Triangle Park, N.C. area.

It operates a manufacturing center in RTP and a customer service operation in Durham.

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