The Medicare Prescription Drug, Improvement, and Modernization Act (MMA) was signed into law in 2003 and took effect on January 1, 2006, adding outpatient prescription drug benefits (commonly known as Medicare Part D) to Medicare health coverage. Medicare Part D was intended to assist beneficiaries to gain access needed to the medications they need outside the hospital setting, thus improving health outcomes and reducing hospital admissions and their associated costs. The principles on which Part D was established were voluntary enrollment, affordable drugs, drug benefits provided by private plans in an open competitive market, and efficient program administration.

The Medicare Program in the United States is a public health insurance program administered by the Department of Health and Human Services (DHHS), through the Centers for Medicare ...