Centene (CNC -0.67%) and WellCare Health Plans (WCG) are on the brink of fusing together. In a joint press release issued after market hours Tuesday, the two companies said that they have "satisfied all regulatory requirements under the merger agreement to complete the pending transaction." This includes a review of the transaction by the Department of Justice.

The approval has been quite some time in coming, as is fairly typical in the healthcare sector. Last March, it was announced that WellCare agreed to be acquired by peer health insurance provider Centene in a deal valued at $17.3 billion at the time. That price is to be paid in a blend of cash and Centene stock.

The regulatory concern was warranted, as the absorption of Centene will make WellCare the largest insurance provider for public healthcare programs such as Medicare and Medicaid.

Stethoscope atop US currency and insurance claim form.

Image source: Getty Images.

Following the announcement of the deal last year, the two companies created a website dedicated to their tie-up. On the site, they say that as one they will have roughly 22 million members in the U.S., with over 12 million clients on Medicaid and approximately 5 million utilizing Medicare.

The site quotes WellCare CEO Ken Burdick as saying that "[w]e are enthusiastic about this combination of two high-performing growth companies focused on government-sponsored managed care, which will bring benefits to all of our stakeholders."

Centene and WellCare say that by combining, they can save around $500 million in annual expenses by the second year following the deal's close, which is expected to occur "on or about" Thursday, Jan. 23.

The prices of both healthcare stocks closed slightly higher on Wednesday.