While lab vacancy rates still remain high at 15%, users of 50,000 sf or more are finding the market for vacant laboratories in this city's biotech corridor rapidly tightening. Adam Subber, a vice president with Cresa, tells GlobeSt.com that the 7% drop in lab vacancy rates is due mainly to a number of large users, including Vertix, which recently announced that it will take three floors at Cambridge's 675 W. Kendall St. Pharmaceutical giant Sanofi Aventis is reportedly looking for 60,000 sf to 70,000 sf for an expanded research site and CombintoRx, which is relocating from Boston, will expand its 245 First St. operation by more than 40,000 SF.

Altus Pharmaceuticals and Shearing Plough are also looking to expand significantly, Subber says. "Earlier this year, there were about half a dozen options available for biotech companies seeking 50,000 to 70,000 sf," Dan Sullivan, also a vice with Cresa, says. "Now, there are only two or three viable options."

The tightening market has also driven up asking rates for lab space from last quarter's $38 to $45 per sf to $40 to $55 per sf in the current quarter, Cresa found. The strengthening of Cambridge's biotech market may also fuel speculative development of lab space in the area, says Subber. Lyme Properties has already said it will proceed with the first phase of its 301 Binney St. project. That will ultimately add 450,000 sf of laboratory space to the market in the area's first speculative development in three years.