Gilead Sciences and Novo Nordisk are leasing new office and laboratory spaces in Seattle.

Gilead Sciences’ research and development division will occupy almost all of a three-story office and laboratory building under construction in Seattle’s South Lake Union neighborhood, the building’s owner said Wednesday.

Alexandria Real Estate Equities said Gilead has signed a long-term lease for 106,000 square feet in the 115,000-square-foot building at 199 E. Blaine St.

The building, across Fairview Avenue East from Lake Union, is scheduled to be completed in 2010.

Separately, BioMed Realty Trust said it has leased 37,000 square feet in its new Fairview Research Center in South Lake Union to a subsidiary of pharmaceutical giant Novo Nordisk. The five-story, 94,000-square-foot building is at Fairview Avenue North and Mercer Street.

A Gilead spokeswoman said the expansion was “just part of normal company growth” and declined to provide more details.

The Foster City, Calif.-based company became one of the top players in Seattle biotechnology research when it acquired homegrown Corus Pharma for $365 million in 2006. The unit, led by Corus founder Bruce Montgomery, continues to specialize in therapies for respiratory ailments.

Having a presence in Seattle allows Gilead to tap into the local biotech talent, Chief Operating Officer John Milligan told The Seattle Times last year.