The next big hurdle for the mega-merger will be in New York, where regulators have threatened to block the deal unless the companies agree not to raise premiums and submit their PBM to state oversight.

California has approved CVS Health Corp.'s $69 billion acquisition of Aetna Inc.

The go-ahead came this week after the two companies agreed to pump $240 million into the California's healthcare infrastructure and guarantee against premium hikes to cover the cost of the deal.

"The Department thoroughly examined this merger and determined enrollees will have continued access to appropriate healthcare services and also imposed conditions that will help increase access and quality of care, remove barriers to care and improve health outcomes," Shelley Rouillard, director of California's Department of Managed Health Care, said in a media release.

The go-ahead marks another big hurdle cleared for a merger that many observers believe could fundamentally change healthcare delivery in the United States and pose a direct challenge to traditional care providers.

The U.S. Department of Justice approved the deal in October, with the stipulation that Aetna sell its Medicare Part D business to WellCare Health Plans.

CVS said earlier this month that it hopes to complete the deal by Thanksgiving.

However, one of the last major state regulatory hurdles is in New York. That state's Department of Financial Services is expected to issue a decision on the merger in the coming weeks, after threatening last month to block the merger unless the companies agreed not to raise premiums and to submit their pharmacy benefits manager to state regulation.

CVS Health and Aetna did not return requests Friday for comment.

In addition to their pledge not to raise premiums to cover the acquisition costs, CDMHC said CVS and Aetna agreed to "keep premium rate increases to a minimum," and to invest nearly $240 million in California's healthcare delivery system.

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