"Old pharmaceutical companies had a need for high security in isolated suburban fortresses," says Hughes. "They didn't want their scientists talking to other scientists."

Roche, part of F. Hoffman-LaRoche, had a major office and research campus in the Nutley area. However, when it acquired biotech firm Genentech in California, Roche centralized research at the Genentech facilities, to take advantage of the company's more nimble structure. Roche is now in the process of selling its Nutley campus, which has been a major presence for decades, says Hughes.

Similarly, Sanofi Aventis in Bridgewater, NJ, which acquired Massachusetts-based Genzyme, has closed its laboratories in New Jersey and moved the bulk of its research to Cambridge, MA. Sanofi's US headquarters remains in Bridgewater, and other pharmaceutical companies maintain administrative and headquarters facilities, such as Johnson & Johnson in New Brunswick, says Hughes.

Millennials are also more interested in working in edgier urban environments, such as the relocation of Glaxo Smith Kline from suburban and Center City locations in the Philadelphia market to a new facility in the Navy Yard in South Philadelphia, near the sports complexes and some trendier restaurants and clubs, he says.