Kyle Walsh | CNBC

PillPack, the Internet pharmacy that Amazon acquired in 2018, has updated its logo and other paperwork to include a new "Amazon Pharmacy" brand, and sources say its CEO has been promoted to vice president within Amazon. Specifically, the group's branding has changed from "PillPack, an Amazon company" to "PillPack by Amazon Pharmacy." It's the first public reference to Amazon Pharmacy, an entity that many analysts expect will eventually do more than mail delivery of medicines through PillPack. Today, PillPack specializes in fulfilling multiple prescriptions and mailing them to customers in clearly labeled packages so they remember to take their pills at the appropriate times. Its customers tend to be older and on multiple medications. But Amazon could enter other areas of the sector by serving patients who have acute medical needs, or by adding a pharmacy to its retail stores, including Whole Foods.

The prescription drug market is worth more than $330 billion, making it a lucrative opportunity for Amazon along with its rivals including Walmart and Costco. These companies are all positioning themselves against traditional drug store chains, like CVS and Walgreens. Costco, as CNBC reported this month, is now piloting a mail delivery service with grocery delivery start-up Instacart, which offers both convenience and affordable prices to its members. In addition to the logo change, PillPack also recently filed paperwork that adds "Amazon Pharmacy" to the licensed name of its pharmacy fulfillment centers in New York, Texas, Florida, Arizona and New Hampshire, a company spokesperson told CNBC. The company said that there won't be any service changes for existing or new customers, and that it will retain its own brand. But customers will be notified in the coming weeks with labels and printed materials that will include references to Amazon Pharmacy. The company also updated its help center page with references to PillPack by Amazon Pharmacy.

A slow integration