Alexandria and Boston Properties to Expand Gateway Commons

Alexandria Real Estate Equities and Boston Properties have a plan to expand a life science complex in South San Francisco by nearly 300,000 square feet.

The Pasadena- and Boston-based life science developers have filed papers to build a 297,000-square-foot, seven-story building with offices and research labs on a parking lot at 555 Gateway Boulevard, the San Francisco Business Times reported.

The 7-acre parcel, co-owned and operated by Boston Properties, would include a 216,000-square-foot parking garage for 623 cars.

The building would expand Gateway Commons, which when completed would include 1.7 million square feet of offices, R&D labs and hotels and shops along Gateway Boulevard between Oyster Point Boulevard and Corporate Drive.

The 117-acre master-planned business development is co-owned by Alexandria and Boston Properties, who formed a 50-50 joint venture in January 2020.

The life science duo are now converting an office building into 300,000 square feet of laboratories at 651 Gateway.

They’ve also begun construction on a 229,000-square-foot building on a parking lot at 751 Gateway. In December 2021, Genentech leased the entire building, expected to open next year.

The joint venture agreement merged properties owned by both companies into a sprawling life science center 8 miles south of Downtown San Francisco.

Boston Properties contributed office buildings it owned at 601, 611 and 651 Gateway totaling some 768,000 square feet, plus developable land.

Alexandria contributed 313,000 square feet of labs, offices and other buildings, plus developable land.

The 297,000-square-foot building at 555 Gateway and 229,000-square-foot building at 751 Gateway would expand Gateway Commons by a combined 742,000 square feet, more than initially planned.

Over the years, Alexandria has built up its real estate portfolio on Gateway Boulevard. The developer solely owns two office buildings at 901 and 951 Gateway, as well as two smaller properties at 600 and 630 Gateway.

But in October, the real estate investment trust walked away from an approved 600,000 square foot life science campus at 100 East Grand Avenue, leaving business partner Prologis in the lurch. Alexandria reported a loss of $30 million in connection with the fizzled deal.

Alexandria, a giant among life science developers, has 432 properties in North America spanning 47.4 million square feet, according to public records in late December. In the Bay Area, it has 67 properties, of which 8.1 million square feet were in operation, 443,388 square feet were in development and more than 300,000 square feet were in redevelopment.

Life sciences R&D facilities on the Peninsula have a vacancy rate of 4.5 percent, according to Colliers.

— Dana Bartholomew