Real estate development firm Campanelli Cos. has signed five leases totaling 22,407 square feet at 300 Crown Colony in Quincy.

MCMC LLC, a national managed care services company, leased 12,072 square feet to relocate from the Marine Industrial Complex in Boston. The company plans to move in November.

Mark Carangelo of Equitable Real Estate Solutions served as MCMC’s broker.

Granite Medical Group, an affiliate of Atrius Health, leased 4,192 square feet to relocate its business office from 500 Congress St. in Quincy to 300 Crown Colony. The company plans to move in October. Granite Medical’s clinical operation will remain at 500 Congress St., according to a statement.

Bob Conrad and Paul McCourt of The Conrad Group Inc. represented Granite Medical Group.

Staffing company On Assignment Inc., has leased 2,173 square feet. The company relocated from 100 Grossman Drive in Braintree in February.

Dan Sullivan of CresaPartners LLC represented On Assignment.

Recent renewals at 300 Crown Colony include The Hanover Co., a national real estate developer, renewing its lease for 2,998 square feet and Vive Communications, a technology solutions provider, renewing a 972-square-feet lease, according to a statement.

"The hands-on local ownership of the Campanelli Cos. has provided our team with the ability to reposition the building and complete over 22,000 square feet of leasing in only four months. Campanelli’s vertically integrated platform provides both existing and prospective tenants with a true sense of professionalism, a key factor when a tenant is considering a long-term lease commitment," said Elcock.