Most of the Medicare Part D prescription plan drug list changes that insurers made in the middle of 2008 and 2009 expanded enrollees' access to drugs, according to the U.S. Government Accountability Office (GAO).
Medicare Part D gives private insurers a vehicle for selling prescription coverage to Medicare enrollees.
The GAO looked at the Part D plans' mid-year changes to drug lists, or "formularies," in response to a request from House Democrats.
In 2008, mid-year formulary changes had the potential to reduce access to drugsfor just 4.9% of enrollees who filled a prescription for a drug that year, Kathleen King, a GAO director, writes in a report summarizing the GAO's mid-year Part D formulary change review.
In those cases, the plan providers, or "sponsors," removed a drug from a formulary or tightened utilization management requirements.
