Biogen has signed a 10-year lease for 80,000 square feet of office and lab space at BioMed Realty Trust’s 301 Binney St. in Cambridge’s Kendall Square, bringing the 417,000-square-foot building to full occupancy.

Ironwood Pharmaceuticals and Living Proof also occupy the building.

Transwestern RBJ’s Steve Purpura and Eric Smith brokered the lease for BioMed. DTZ represented Biogen.

The move is the latest among life science companies jockeying for space in the neighborhood. Akamai Technologies recently leased 100,000 square feet at BioMed’s 50 Hampshire complex, which was recently renovated.

Genzyme Corp., which occupies 350,000 square feet at BioMed’s 500 Kendall Square, announced last week it will move to a new 251,000-square-foot headquarters at 50 Binney St. in 2018. Alexandria Real Estate Equities is developing that site into a 1-million-square-foot biotech cluster.

The vacancy rate for class A office and lab space in East Cambridge was 7.3 percent in the first quarter, with average rents of $63.28, according to a first-quarter market report by DTZ.