The Centers for Medicare & Medicaid Services proposed two mandatory payment demonstration programs that would test most‑favored‑nation‑style pricing for Medicare Parts B and D drugs by aligning U.S. payments with prices paid in comparable countries. The administration frames the pilots as a mechanism to lower Medicare drug spending and beneficiary out‑of‑pocket costs, while industry groups are expected to mount legal and lobbying challenges. Implementation could begin in 2027 and would represent one of the most consequential U.S. experiments in drug pricing policy, with broad implications for manufacturer revenue and access strategies.