This isn't the first paid delivery of any kind from UPS. The company has a deal to shuttle medical samples between WakeMed facilities in Raleigh. That's a commercial arrangement over areas that are under a company's control. Now, it's flying in residential areas and delivering to everyday people. Alphabet's Wing is already delivering medicine as part of a pilot program, but that's limited to over-the-counter medication, gifts and snacks.
It's not exactly a booming business with just two deliveries. However, it's still a significant milestone. The deliveries point to a future where you don't have to travel to the pharmacy, or else wait for a courier truck to make its usual rounds -- you could get the medicine you need within minutes of your supply running out. It also bodes well for mainstream adoption of drone delivery, even if it's likely to be a long while before you can assume your prescription pills will descend from the skies.