CVS Health completed its $69 billion acquisition of health insurer Aetna on Wednesday, in a move widely anticipated to transform the U.S. healthcare system with similar mergers ahead.

The agreement will combine the companies’ coverage options with drugstore capabilities and a pharmacy benefits platform. Both sides expect that their customers will be able to benefit from the services they deliver and keep patients out of the emergency room, as they will receive much of their primary care from CVS MinuteClinics.