ARIAD Pharmaceuticals Inc. has agreed to occupy the remaining 142,000 square feet of space available for development at Alexandria Real Estate Equities’ 75/125 Binney St. facility in Cambridge.

The lease announcement follows a 15-year lease ARIAD signed for approximately 244,000 square feet at the Kendall Square project known as the Alexandria Center. The lease amendment brings ARIAD’s total space leased to approximately 386,000 square feet, or 99.5 percent, of the project. The remaining 2,000 square feet of space is slated for retail.

Alexandria expects to deliver the 75/125 Binney St. facility to ARIAD in the first quarter of 2015.

Along with ARIAD’s lease, Alexandria announced the execution of a construction loan for approximately $250 million. The lenders include The Bank of New York Mellon as the lead, along with Union Bank, TD Bank and Compass Bank. The term of the loan is four years and Alexandria has the right to extend it for an additional year. The loan has a variable interest rate of Libor + 135 basis points.

The Alexandria Center’s 11-acre "science park" will feature four ground-up developments – 50 Binney St., 75/125 Binney St., 100 Binney St. and 225 Binney St. – comprising approximately 1.7 million square feet of laboratory and office space, as well as approximately 200,000 square feet of residential space. In 2011, Alexandria kicked off Alexandria Center development with an approximately 305,000-square-foot build-to-suit for Biogen Idec Inc. at 225 Binney St.