Shares of CVS Health tumbled Friday with other drugstore chains following a report it could acquire insurer Aetna to fortify itself against a possible Amazon entry into the sector.

CVS Health has offered to buy Aetna for more than $200 per share, The Wall Street Journal reported late Thursday, citing people familiar with the matter.

The newspaper described the talks as serious, but said they may not lead to a deal.

Around 1630 GMT, CVS Health was down 4.8 percent to $69.75, while rivals Rite Aid dropped 4.5 percent and Walgreens Boots Alliance 3.9 percent.

Aetna, which spiked 11.5 percent in the final moments of trading Thursday afternoon following the Journal's report, dipped 1.4 percent to $177.73, holding most of its gains.

The possible deal comes amid signs that Amazon is preparing to expand into pharmacy distribution.

A report in the St. Louis Post-Dispatch said Amazon, which has disrupted the grocery business with its $13.7 billion acquisition of Whole Foods Market, had obtained licenses in 12 states to become a wholesale pharmaceutical distributor.

"While these licenses do not seemingly permit (Amazon) to act as a dispensing pharmacy, it does allow it to deliver relevant pharmaceutical and medical products to pharmacies," said a note from Credit Suisse.

"We can only speculate as to what Amazon's next steps may be," the note added.

"While we acknowledge the inherent challenges and complexities of the supply chain, the specter of Amazon continues to weigh on sentiment across our universe of distributors, pharmacies, and (pharmacy benefit managers)."

CFRA Research analyst Joe Agnese said Amazon's move was the "big threat for the sector right now."

Source: AFP