Image courtesy of SMMA

BioMed Realty’s appetite for life science sites in Boston continues with the pending acquisition of a speculative office building nearing completion in South End.

The firm confirmed it has 321 Harrison Ave. under agreement and is seeking approval for 220,000-square-foot office-to-lab conversion. The core-and-shell is scheduled for completion in March, and BioMed is seeking Boston Planning & Development Agency approval for changeover to life science use.

The 11-story building broke ground on speculation in April 2018 in a partnership between Burlington-based Nordblom Co. and CIM Group of Los Angeles. Built atop an existing parking garage, the building features 29,000-square-foot floor plates.

To accommodate the more powerful building systems needed in lab space, the revised project would include new penthouse space and roof screening for mechanical equipment, and a new fourth-floor pedestrian bridge connecting to the neighboring 1000 Washington St. office building.

It’s the latest BioMed purchase of existing or permitted developments, a reflection of biotech and pharmaceutical companies’ quick timelines for occupancy.

In January, BioMed completed its $163 million acquisition of the Xmbly site in Somerville’s Assembly Square, where Cresset Group and Novaya Real Estate Ventures had obtained approval for 1.3 million square feet of office, lab and retail space.

Also last month, San Diego-based BioMed paid $362 million for the ground lease on 601 Congress St. in the Seaport District, the former John Hancock headquarters, with plans to convert most of the floors into life science space.