Ann Arbor's 2 million-square-foot ex-Pfizer complex is no longer empty.

The University of Michigan, which acquired the 30-building, 174-acre site in June for $108 million, today moved its first employees to the complex. That group - 30 employees from the U-M Medical School's Institutional Review Board office - is occupying offices near the southeast corner of Huron Parkway and Plymouth Road.

The University of Michigan today moved its first employees to the ex-Pfizer site in northern Ann Arbor.

Until now, a few U-M staff members responsible for the site's repositioning were alone in roaming the halls of the campus, which has been renamed North Campus Research Complex. The move follows U-M's announcement in January that it had identified various departments representing 300 employees who would be the first to move to the ex-Pfizer site.

"Today is a major milestone in the development of the North Campus Research Complex, and we welcome this pioneering group of employees," U-M Health System CEO and Executive Vice President for Medical Affairs Ora Pescovitz said in a statement.

In April, several departments will join the Institutional Review Board office at the site. They include the U-M Comprehensive Cancer Center's development and clinical trial offices; the Michigan Institute for Clinical & Health Research; and the Medical School Office of Research's Calendar Review and Analysis Office.

Contact AnnArbor.com’s Nathan Bomey at (734) 623-2587 or nathanbomey@annarbor.com or follow him on Twitter. You can also subscribe to AnnArbor.com Business Review's weekly e-newsletter or the upcoming breaking business news e-newsletter.