More life science firms are heading to the end of the Red Line.

Arbor Biotechnologies, Kintai Therapeutics and Simcere Innovation have all signed leases at Building 400-500 at Cambridge Discovery Park, developer Bulfinch announced Monday. The 283K SF lab and office building currently under construction is the last of the office and lab projects slated for the 27-acre development near the Alewife Red Line station.

Arbor will take just over 36K SF on the fifth floor, Kintai has a 72K SF lease across the third and fourth floors and Simcere will lease more than 26K SF on the second floor. FogPharma previously announced a lease for nearly half the building, leaving only a 32K SF availability on the sixth floor.

“We are extremely pleased to announce that Arbor, Kintai and Simcere Innovation have chosen to select CDP’s newest Building 400‐500, bringing the total occupancy at the property to 88%,” Bulfinch Senior Vice President and Director of Leasing Mike Wilcox said in a prepared statement. “Multiple leases signed prior to the building’s completion demonstrates the desire for additional lab, office and R+D space outside of Kendall Square that still maintains convenient access to the MBTA’s Red Line and ‘brain train.'”

As Kendall Square and East Cambridge have becoming some of the tightest life science markets in the world, West Cambridge and Alewife have grown in popularity due to their similar Red Line proximity, access to talent at Harvard and MIT and easy commute to suburbs up Route 2. Kendall Square office rents averaged $97/SF in Q2 compared to $57/SF in West Cambridge, according to Perry data.

Bulfinch Cos. expects to open Building 400-500 at Cambridge Discovery Park by March 2020.