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Part D Plans Generally Include Drugs Commonly Used by Dual Eligibles: 2015


This memorandum report fulfills the annual reporting mandate from the Patient Protection and Affordable Care Act (ACA) for 2015. The ACA requires that OIG conduct a study of the extent to which formularies used by stand-alone prescription drug plans and Medicare Advantage prescription drug plans (referred to jointly as Part D plans) under Medicare Part D include drugs commonly used by full-benefit dual-eligible individuals (i.e., individuals who are eligible for both Medicare and full Medicaid benefits). Pursuant to the ACA, OIG must annually issue a report with recommendations as appropriate. This is the fifth report the OIG has produced to meet this mandate.


For this memorandum report, we determined whether the 341 unique formularies used by the 3,152 Part D plans operating in 2015 cover the 200 drugs most commonly used by dual eligibles. We also determined the extent to which those commonly used drugs are subject to utilization management tools. To create the list of the 200 drugs most commonly used by dual eligibles, we used the 2011 Medicare Current Beneficiary Survey. Of these 200 drugs, 196 are eligible for Part D prescription drug coverage, 3 are excluded from coverage, and 1 is no longer prescribed in the form taken by beneficiaries.


Overall, we found that the rate of Part D plan formularies' inclusion of the 196 drugs commonly used by dual eligibles is high, with some variation. On average, Part D plan formularies include 95 percent of the 196 commonly used drugs. In addition, 71 percent of the commonly used drugs are included by all Part D plan formularies. These results are largely unchanged from OIG's findings for formularies reported in the related 2014 mandated annual report.

We also found that the percentage of drugs subject to utilization management tools remained relatively the same from 2014 to 2015. On average, formularies applied utilization management tools to 29 percent of the unique drugs we reviewed in 2015, compared to 28 percent of those we reviewed in 2014.

This report does not contain recommendations.