Why do U.S. drug prices rise after launch while foreign prices fall?

AARP data show that list prices for 25 top brand-name drugs have increased an average of 81% in the U.S. since launch, while falling 13% across 19 peer nations through April 2026. The gap reflects structural differences in pricing systems: U.S. drugs tend to launch high and keep rising, whereas other countries use price reviews to drive them down over time.