Photo courtesy of Samules & Assoc.

Alexandria Real Estate Equities’ search for promising growth corridors for life science outside of Cambridge has led to the Fenway with a $1.52 billion agreement to buy Samuels & Assoc.’s 1.8 million-square-foot portfolio, including plans for an additional 400,000-square-foot office-lab building.

The purchase includes the nearly 1 million-square-foot 401 Park Drive, the former Landmark Center property which was repositioned by Boston-based Samuels during 10 years of ownership to attract new office tenants. Currently 93 percent leased, 401 Park Drive includes 221,000 square feet that can be converted for lab space, Alexandria said in an SEC filing.

Alexandria said it will seek approval for an additional 400,000-square-foot office-lab building, which if approved, would increase the purchase price by $98 million.

Samuels also is constructing a new 510,000-square-foot office-lab tower at 201 Brookline Ave. which is already 17 percent leased to venture capital firm Third Rock Ventures and Cambridge-based Tango Therapeutics. The building is scheduled for completion in 2022.

After acquiring the Landmark Center in 2011 for $530 million with investment partner J.P. Morgan, Samuels repositioned the former Sears warehouse and office building to attract tech startup Toast as a major tenant, and converted former retail space into the Time Out Market food hall which opened in 2019.

The Fenway’s potential emergence as a life science cluster is also being pursued by Related Beal, which recently redesigned its Kenmore Square redevelopment of Boston University-owned properties to add 117,000 square feet of lab-ready space, and a partnership between Meredith Management and IQHQ on the 720,000-square-foot Fenway Center air rights project.