Exelixis Inc., a Calif. biotech company, targeted King of Prussia to hold its East Coast operations. However, absent a building it found suitable, it is now eyeing a built-to-suit facility. Natalie Kostelni unrolled the blueprints on this proposed structure in the Philadelphia Business Journal.

Exelixis is presently working with Brandywine Trust Realty to develop a King of Prussia plot on Park Ave., east of 1st Ave., near the Valley Forge Casino Resort. It seeks 200,000–250,000 square feet, split among offices and labs.

“Exelixis decided to locate its East Coast office in King of Prussia due to its convenience and accessibility to much of the Greater Phila. and central New Jersey talent base,” read a corporate email explaining the interest. “Access to this talent pool will allow the company to broaden its employee base to meet the goals of our ambitious expansion plans in the coming years.”

Exelixis anticipates more than 600 employees to eventually work on Park Ave. The biotech company said that an agreement with Brandywine had yet to be reached on the development and that the timing and planning for it is underway.

For the time being, Exelixis is making do with a temporary office on Freedom Business Center Drive (a short distance from Park Ave.) and rented lab space in Radnor.

Exelixis’ business focus is cancer treatments.

More on this expansion of commercial space in King of Prussia is at the Philadelphia Business Journal.