SAN FRANCISCO — A possible $66 billion takeover of health insurer Aetna by CVS Health could lower costs to both companies, leading to the hope that at least some savings might be passed through to patients.

On Thursday, the Wall Street Journal, citing unnamed people who said they are familiar with situation, reported CVS Healthcare was in talks to acquire Aetna for more than $200 per share. Representatives of both companies declined to comment on the report.

While at first glance, a bid by CVS, with its 9,000 national pharmacies, for Aetna might seem like the mouse swallowing the cat, it's actually the opposite. The market capitalization of CVS is currently about three times that of Aetna, approximately $180 billion versus $60 billion.

There are other facets to its business that make an insurance company an interesting target for a pharmacy, experts say.

Pharmacy benefit management

An important part of CVS' business is CVS Caremark, the pharmacy benefit management subsidiary of CVS Health. Pharmacy benefit management companies work with insurers to decide which drugs are most beneficial and cost-efficient. They also negotiate discounts from drug manufacturers.

"Aetna participants are likely to see the most benefit … because CVS would be maybe able to offer them lower co-pays if they shop with them," said Joseph Agnese, a senior analyst with investment research firm CFRA.

Agnese says don't expect the deep discounts, but he adds that "the more (CVS) is purchasing, the better the deals they'll be able to get (from drug companies)."

CVS Caremark has expertise and access to customers’ pharmaceutical information and medical needs, so it makes sense that the company would want to expand that to include not just pharmacy, but full health care, says Mohamed Jalloh, a spokesman for the American Pharmacists Association.

“It could be that they’re trying to expand their service and extend the pharmacy insurance benefit to insuring everything,” said Jalloh.

A linked Aetna-CVS could presumably better manage the cost of prescription drugs, driving utilization toward better value products and getting a better deal on pharmaceuticals, said Laurence Baker, chair of the Department of Health Research and Policy at Stanford University Medical School.

Baker notes that CVS and Aetna aren’t the only companies doing this dance. UnitedHealth, for example, also works with a closely affiliated PBM that it built.

Not everyone is convinced prices could come down for customers.

In a time of rising health care costs and bitter partisan fights over insurance and accessibility, the potential merger may mean more savings for the companies than individual users.

The merger is in many ways an indication for the pharmacy benefit management (PBM) industry “that the jig is up,” said Adams Dudley, a professor of medicine and health policy at the University of California, San Francisco.

“The idea of a PBM was that they would negotiate really well and really hard with the drug companies, and that the insurers didn’t have the knowledge or the bandwidth to do that,” said Dudley, who directs the UCSF Center for Healthcare Value.

“But it’s become apparent that they’re not saving people money, because they keep all the profits themselves. People are suddenly realizing that if PBMs make a lot of profit, it just jacks up drug prices. It’s completely the opposite of what we thought they would do,” Dudley said.

The merger wouldn’t likely save much money for consumers, in the opinion of Aaron Katz, an expert on health policy at the University of Washington’s school of public health.

That doesn't necessarily mean it wouldn’t save money for the companies. “Larger entities tend to be tougher negotiators over price and contracts,” said Katz.

While the proponents of health company mergers often cite the cost savings of merged systems and the benefit to consumers, “I haven’t seen much convincing evidence myself,” said Katz.

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Wider offerings would help

Frustration over the unrealized savings that PBMs were supposed to bring could be a reason for CVS Healthcare to look to widen its reach to a broader swath of health care, should the lucrative PBM business go away.

“They skim an awful lot off the top. Their administrative profits are very high and that might not be sustainable in the future,” Dudley said. As an example, he noted the low prices big box stores such as Costco are able to offer because they purchase directly from the manufacturers, saving the cut the PBMs were taking.

CVS is already on its way to expanding its offerings. The company currently runs more than 1,000 MinuteClinics staffed by nurse practitioners and physician assistants who can provide basic health care for walk-in patients.

For Aetna, mergers are a road it's been down. Two years ago it agreed to buy Louisville, Ky-based insurer Humana for $34 billion. However, the deal was abandoned earlier this year due to regulatory concerns.

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