To amend part D of title XVIII of the Social Security Act, as added by the Medicare Prescription Drug, Improvement, and Modernization Act of 2003, to permit the Secretary of Health and Human Services to enter into direct negotiations to promote best prices for Medicare beneficiaries.

Amends part D (Voluntary Prescription Drug Benefit Program) of title XVIII (Medicare) of the Social Security Act, as added by the Medicare Prescription Drug, Improvement, and Modernization Act of 2003, to authorize the Secretary of Health and Human Services to enter into direct negotiations between drug manufacturers and pharmacies, and between Medicare prescription drug plan sponsors and Medicare Advantage organizations offering prescription drug plans, to promote the best prices of prescription drugs for Medicare beneficiaries.