The nation’s medicine chest is sporting a few empty spaces on its shelves these days, thanks to layoffs and decisions to locate select operations in other locales. The recent decision by Bristol-Myers Squibb to downsize seems to epitomize concerns, however, that New Jersey is losing its long-running boasting rights about being the home address for big pharma.

“New Jersey and its research facilities here are more closely linked to chemical-based pharma,” Jim Hughes, a Rutgers University economist and dean of the Edward J. Bloustein School of Planning and Public Policy, tells The Trenton Times. “New Jersey is at a disad vantage there. We don’t have the same depth of biosciences as other places. That’s worrisome, I guess.”

Drugmakers interested in biotech research increasingly want to locate their facilities in what Hughes called “centers of excellence in life sciences,” places that already have groups of hospitals, medical complexes and universities. The San Diego area is one such cluster. The Bay Area of California is another. A third is in the Boston/Cambridge area of Massachusetts, where Merck and Novartis are expanding. That’s also where Bristol-Myers is building its new biologics center that will be completed next year, the Times writes.

“Clearly, one of the reasons we selected the site we did, it’s a specialized process that requires a skilled labor force. A lot of that kind of work is already being done in Massachussetts. It has a built-in talent base,” a Bristol-Myers spokesman tells the paper.

As usual, numbers tell a story. New Jersey’s percentage of the nation’s total pharmaceuticals employment has slipped to 13.8 percent from 20 percent in 1990, says Hughes. At the time, its pharma jobs numbered about 40,000, and that figure has held steady. But California now has 46,000 jobs, up from 23,000. The change reflects the shift toward biotech. “We are in the last stages of the old business model,” says Hughes.