A study showed that increases in prices of brand-name drugs in the U.S. were largely driven by year-over-year price increases of drugs that were already in the market rather than because of new therapies or improvements in existing medications.

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A study showed that increases in prices of brand-name drugs in the U.S. were largely driven by year-over-year price increases of drugs that were already in the market rather than because of new therapies or improvements in existing medications.