But drug makers and trade associations have filed multiple lawsuits challenging the program, which is designed to lower costs for Medicare patients.

“Everybody negotiates prices,” Tanden told Phang. “What the pharmaceutical companies are doing are they’re going to the courts to ensure that they can charge any price they can get away with, and that is wrong.”

Tanden also said she expects the program to be expanded, with 15 or 20 drugs added in future installments.

“It’s really important to remember that for medications that aren’t on this list, they may be on future lists,” she said, noting that “prices have been lowered already for insulin.”