Walmart has been making forays into consumer health care for more than a decade. Now, the nation's largest retailer may be looking to play a bigger role in the sector by acquiring Medicare insurance giant Humana — just as its rival Amazon is increasingly making its own moves in the health-care market.
Walmart and Humana are having early-stage talks about strengthening their existing partnership, people familiar with the matter tell CNBC. As part of those talks, an acquisition has also been discussed, but such deal talks are very early stage and may not happen.
For Walmart, a deal to buy Humana would not come cheap: The health insurer had a market valuation of $37 billion, as of Thursday's close. Aetna's failed 2015 acquisition of Humana was valued at $54 billion.
The firms have held preliminary talks exploring a possible combination, including a potential merger, according to the Wall Street Journal.
"Humana is potentially an attractive asset for Walmart as it would help diversify its revenue stream," Cantor Fitzgerald health insurance analyst Steven Halper wrote in a recent report, noting that the retailer and insurer already partner on a co-branded Medicare prescription drug plan.
"But our industry contacts suggest that Humana has been minimizing its relationship with Walmart recently," Halper added.
Walmart may very well want to reinforce its partnership now, partly in response to retail pharmacy giant CVS Health's $69 billion deal to acquire insurer Aetna, and health Cigna's $54 billion proposed merger with pharmacy benefits manager Express Scripts. Additionally, there is a threat of online retailer Amazon's potential entry into the pharmacy business.
"I think it's interesting to contemplate what the disruption could bring because I think that it makes everybody more creative in how they think about what's possible," said Tracy Watts, senior partner at health benefits consulting firm Mercer.
"That's some of the good that has come out of these various types of partnerships and merger announcements," Watts said.
The key for all of these deals is whether they can provide consumers with a more affordable and effective new health care model.
CVS and Aetna are proposing to use pharmacy clinics to provide coordinated, personalized medical care for members with chronic conditions at a lower cost, by leveraging prescription and medical data.
Yet some analysts say a Walmart-Humana combination has the potential to be even more transformative. Humana already has its own pharmacy benefits unit, and has launched nearly 200 standalone clinics to help manage chronic conditions for its Medicare members.
Walmart has pharmacies in most of its 4,700 stores and Sam Club brands, and in-store clinics in Georgia, South Carolina, and Texas. An expanded partnership or merger with Humana catering to Medicare patients could help the retailer become a major provider of primary care.
"The healthcare organization that accurately captures and analyzes the data of the fast-growing U.S. demographic — seniors — stands to lead the industry of the future," said Dr. David Friend, managing director at consulting firm BDO.
Walmart has also tried to promote its in-store clinics as a lower cost point of primary care for its workers. As the nation's single largest employer, with more than 1.5 million workers, acquiring an insurer could ostensibly help Walmart bring down health costs for its own workforce.
Still, buying a health-care company for its own employees' benefit "would be a terrible reason, because you paid for the value of Humana upfront when you purchased them," said Craig Garthwaite, director of the Health Enterprise Management Program at Northwestern University's Kellogg School of Management.
Still, large employers are pushing for new models to reign in health costs and improve care. Amazon, Berkshire Hathaway, and J.P. Morgan Chase have joined together to create a firm, which will try to reduce costs and improve care for their combined workforces of 1 million people.
Three years ago, when four of the major health insurers rushed to partner on large-scale mergers, the deals were blocked by the Department of Justice, and ultimately rejected by the courts on anti-trust grounds.
Analysts say the CVS-Aetna and Cigna-Express Scripts deals are different, because they are not mergers of rivals but rather vertical deals which would not result in fewer competitors in the medical or pharmacy benefit markets.
"On the anti-trust side, I don't see huge issues… with any of these three vertical mergers," said Garthwaite, though he added that integrated medical pharmacy benefits firms could make it harder for new standalone entrants.
"If the barrier to entry is that everyone really likes having their insurer and their provider integrated together that it creates a much more attractive insurance class, then we should allow that activity to happen and we should regulate it," he explained.
"It shouldn't be that we say we're not going to allow a good product to emerge because we're afraid," Garthwaite added.
Last month, the Department of Justice asked CVS and Aetna extended its review of the merger, asking the companies for more information. The firms still expect the deal to be approved in the second half of the year.
Even if regulators sign off on the deals, there are risks to execution for both Walmart and CVS, as they try to integrate health insurance, pharmacy, and primary care services at such a large scale.
But Mercer's Watts says even if the deals aren't realized, health-care firms are clearly searching for a model that will provide more value and better care for consumers.
"The fact that people gravitate to how much better something could be in some of these partnerships — I think that's good. I think that in the long term that's good for health care delivery," Watts said.
—CNBC's Lauren Hirsch contributed to this report.