<Li> Signed into law by President George W. Bush on December 8, 2003 </Li> <P> The Medicare Prescription Drug, Improvement, and Modernization Act, also called the Medicare Modernization Act or MMA, is a federal law of the United States, enacted in 2003 . It produced the largest overhaul of Medicare in the public health program's 38 - year history . </P> <P> The MMA was signed by President George W. Bush on December 8, 2003, after passing in Congress by a close margin . </P> <P> The MMA's most touted feature is the introduction of an entitlement benefit for prescription drugs, through tax breaks and subsidies . </P>

Who signed into law the expansion of the medicare prescription benefit