To amend part D of title XVIII of the Social Security Act to prohibit mid-year changes in the formularies of Medicare Part D plans.

[AI summary unavailable — showing source text] Amends part D (Voluntary Prescription Drug Benefit Program) of title XVIII (Medicare) of the Social Security Act to require changes in formularies of Medicare part D prescription drug plans to be effective only at the beginning of a plan year. (Thus prohibits mid-year changes.)…