Image courtesy of Alexandria Real Estate Equities Inc.

A high-profile development site on Boston’s Fort Point Channel will become the home of a new $700 million Eli Lilly and Co. life science research institute.

The Indianapolis pharmaceutical company leased 334,000 square feet at 15 Necco St., a 12-story office-lab building being developed by Alexandria Real Estate Equities and National Development.

The property will become the new Lilly Institute for Genetic Medicine, conducting research on RNA- and DNA-based therapies. Occupancy is scheduled for 2024, Eli Lilly and Co. said.

The property was originally eyed for an expansion of General Electric’s Seaport District headquarters before GE shelved plans for a new signature office building on Fort Point Channel amid corporate cost-cutting.

Up to 250 researchers based at 15 Necco St. will collaborate with 200 Ely Lilly scientists based in New York, where the company acquired gene therapy firm Prevail Therapeutics in 2020.

Prevail Therapeutics at Lilly CEO Franz Hefti will be co-director of the Institute.

The 15 Necco St. building also will include shared incubator space with capacity for 150 researchers from local startups, Eli Lilly and Co. said.

Alexandria now owns nearly 39 million square feet of operating properties in North America, including 10 million square feet in Greater Boston. The company has another 2.4 million square feet of development and redevelopment projects in the region including the Necco Street property.

“15 Necco, designed to be a unique and inspiring facility, represents a critical piece of our remarkable value-creation pipeline, and we are thrilled to bring an anchor tenant to this unparalleled location in the Seaport, where we are pioneering a new life science submarket,” Alexandria co-CEO Peter Moglia said in a statement.

Designed by Elkus Manfredi Architects, the building will include a roof deck, flexile workspaces, open space bordering the Boston Harborwalk and public ground-floor workspace, retail/restaurant tenants and a public dock.

Boston officials filed plans in January to construct a 2,090-foot-long earthen berm along Fort Point Channel to protect 15 Necco and neighboring properties from rising sea levels.