Cambridge officials have approved Needham-based Bulfinch Cos.’ plans to build a 150-room AC by Marriott Hotel and two new office-lab buildings in Cambridge Discovery Park, a 27-acre campus and former Arthur D. Little headquarters in Alewife.

The planning board this week approved 400,000 square feet of new development within the office park that Bulfinch Cos. acquired in 2000.

The master-planned park currently contains 820,000 square feet of office and lab buildings occupied by the Forrester Research headquarters, Genocea Biosciences and the Harvard-Smithsonian Center for Astrophysics, along with a 650-space parking garage.

The board amended the master plan special permit to allow two new office-lab buildings, a 456-space parking garage and the hotel. The four-story, 82,400-square-foot hotel would be located along Route 2 and contain a restaurant, a fitness center, swimming pool and meeting space. Construction will begin by April 1, Bulfinch Cos. President Robert Schlager said, with completion expected in summer 2016.

Bulfinch Cos. is in negotiations with a tenant for one of the build-to-suit office and lab sites. Bulfinch is competing with East Cambridge properties, where rents are significantly higher. It’s also marketing the sites to suburban tenants wanting accessibility to the MBTA’s Red Line.

"This would be a great opportunity for a flagship type of life science tenant," Schlager said.

The new development would cover approximately six acres of the site. Bulfinch Cos. sold the Forrester Research headquarters, which occupies Building 100 in the park, in October but retains ownership of the rest of the property.

The hotel replaces a 200,000-square-foot office-lab building previously approved for the site.

Newton-based National Development announced last week that it will build a 200-room AC by Marriott Hotel next to its Ink Block residential and retail development in Boston’s South End. A 152-room AC By Marriott is under construction at Station Landing in Medford.