CVS health plans to acquire Humana, according to a source with knowledge of the talks.

The deal will add to a raft of health-care deals that CVS and other health care companies have struck in recent years.

The deal is subject to approval by U.S. regulators and would be the largest health-related transaction in history.CVS Health’s purchase would make it the biggest U.K. health- care company in history, surpassing Covid-19 treatment plans.

The acquisition would bring in $6.4 billion to $8 billion in annual revenue for the companies, according a person familiar with the talks, who spoke on condition of anonymity to discuss private negotiations.

CVS plans to use the money to build a new $3.8 billion headquarters in Cleveland and other facilities in the state.

The CVS acquisition would add $2.8 trillion to $4.4 trillion to CVS’s $27 trillion stock market value, according the person, who requested anonymity because the company has not publicly disclosed the terms of the deal.

Shares of CVS rose 3% in after-hours trading.