New law will cut link between PBM pay and drug prices in Medicare from 2028

Pharmacy benefit managers working for Medicare Part D plans will be barred from earning fees tied to drug prices or rebates from 2028, under reforms in the Consolidated Appropriations Act, 2026.

The spending law, signed on February 3, limits PBM compensation to flat, fair-market-value bona fide service fees. Those fees cannot vary with a drug's price, rebates, formulary decisions or referral volume, Mintz noted. PBMs must also pass manufacturer rebates through, AJMC reported.

The change targets a long-standing concern that intermediaries paid on rebates have an incentive to favor higher-priced drugs. That issue is pertinent in rare diseases such as ATTR-CM, where newer drugs such as BridgeBio's Attruby must compete for formulary position against established products such as Pfizer's Vyndamax.

The details are still being worked out. CMS is drafting implementation rules, Pharmacy Times reported in September. Lawyers have warned that flat-fee requirements may be hard to apply when service volumes are unpredictable.