Drug giant Pfizer Inc. said it is planning to relocate the majority of its 530 employees at research facilities in the Alewife neighborhood of Cambridge to Kendall Square in Cambridge; sometime next year, they will join roughly 400 Pfizer employees who are already working in Kendall Square, a hotbed of the life sciences industry.

Pfizer said it plans to hire a broker to explore either selling or subleasing four buildings in Cambridge, including three on Cambridge Park Drive in Alewife.

Pfizer said one reason for the move is that it is looking to make the most efficient use of its global real estate. Another reason: Pfizer wants to create a single, integrated research-and-development community that can easily access and collaborate with world-class biomedical researchers and other partners.

Advertisement - Continue Reading Below

In Kendall Square, meanwhile, a building at 610 Main St. is under construction. Pfizer expects that building to be ready for its first occupants early next year. Most employees from the Alewife facilities will move there. Other Alewife employees will relocate to existing Pfizer space at 700 Main St., though others could be transferred to a Pfizer complex in Andover, the company said.

“We expect that there will be minimal impact to the size of Pfizer’s workforce in the state of Massachusetts, given that most colleagues will be moving to other Pfizer sites or leased space in Massachusetts,” a Pfizer spokeswoman said in an e-mail.

“Pfizer remains committed to maintaining its presence in Massachusetts, given the state’s support for the biopharmaceutical industry,” she added.

The plan is to begin to vacate Pfizer’s campus at Cambridge Park Drive toward the end of 2013, with the majority of the move taking place in early 2014, Pfizer said.

Some of Pfizer’s Cambridge employees are new arrivals. In early 2011, the company said it was shifting some research-and-development operations from Groton, Conn., to Greater Boston as part of a larger plan to cut costs.

The Cambridge buildings that Pfizer plans to either sell or sub-lease are 87 Cambridge Park Drive, 200 Cambridge Park Drive, 35 Cambridge Park Drive, and 620 Memorial Drive.