Terms of the deal were not disclosed. MedExpress runs 141 urgent-care clinics in 11 states. This year, MedExpress plans to open 25 to 30 additional clinics, which house practitioners who treat routine injuries and illnesses.
Optum provides consulting, management and data analytics services to hospitals, payers and other healthcare companies. It has also become a large, profitable division of UnitedHealth, the largest health insurance company in the country by revenue.
The MedExpress deal puts UnitedHealth in the low-cost provider setting, and it builds off two other acquisitions Optum disclosed last year. In September, Optum agreed to acquire MedSynergies, a physician practice consulting firm. It bought care-monitoring company Alere Health for $600 million a month later.
OptumRx, the pharmacy benefits division of UnitedHealth and Optum, also has been actively expanding. In March, OptumRx and Catamaran Corp. agreed to merge, creating the third-largest pharmacy benefits manager in the country behind Express Scripts Holding Co. and CVS Health Corp.
UnitedHealth will release first-quarter earnings for 2015 next Thursday. Optum represented about 37% of UnitedHealth's $130.5 billion of revenue in 2014.