To amend title XVIII of the Social Security Act to require PDP sponsors of a prescription drug plan under part D of the Medicare program that use a formulary to include certain generic drugs and biosimilar biological products on such formulary, and for other purposes.

HR8143 requires Medicare Part D prescription drug plans to include certain generic drugs and biosimilar biological products on their formularies. This bill directly forces PBMs and health plans to prioritize lower-cost alternatives, increasing competition for brand-name pharmaceuticals. The immediate impact is a shift in market share from patented drugs to generics and biosimilars, reducing revenue for companies heavily reliant on brand-name drug sales. The money trail for this legislation involves reduced spending by Medicare Part D plans on higher-cost brand-name drugs. This translates to lower reimbursement rates for brand-name manufacturers and increased purchasing power for generic and biosimilar manufacturers. Companies like Teva Pharmaceutical Industries ($TEVA) and Viatris ($VTRS), which specialize in generics and biosimilars, are positioned to capture increased market share and revenue. Conversely, pharmaceutical giants such as Pfizer ($PFE), Johnson & Johnson ($JNJ), and Merck ($MRK), which derive significant revenue from patented drugs, will experience revenue pressure as their products face mandatory competition on formularies. Pharmacy benefit managers (PBMs) like CVS Health ($CVS) and Walgreens Boots Alliance ($WBA), and health insurers like UnitedHealth Group ($UNH) and Humana ($HUM) that operate Part D plans, will see their formulary management dictated, potentially impacting their rebate structures and profit margins on brand-name drugs. Historically, similar legislative efforts to increase generic drug utilization have impacted pharmaceutical pricing. For example, the Medicare Prescription Drug, Improvement, and Modernization Act of 2003, which established Medicare Part D, led to increased generic drug use over time. While not a direct mandate on formularies, the introduction of Part D created a market where generic substitution became a key cost-saving mechanism. More recently, the Inflation Reduction Act (IRA) of 2022 included provisions for Medicare drug price negotiation, which, while different in mechanism, also aimed to reduce drug costs. Following the IRA's passage, major pharmaceutical stocks like $PFE and $JNJ saw declines of 5-10% in the months following its enactment as investors priced in future revenue impacts. This bill, by mandating formulary inclusion, creates a direct and immediate pressure point for brand-name drug sales. Specific winners include generic and biosimilar manufacturers such as Teva Pharmaceutical Industries ($TEVA) and Viatris ($VTRS), which will see increased demand for their products. Amgen ($AMGN), with its strong biosimilar pipeline, also stands to gain. Losers are pharmaceutical companies heavily reliant on brand-name drug sales, including Pfizer ($PFE), Johnson & Johnson ($JNJ), and Merck ($MRK). PBMs and health plans like CVS Health ($CVS), Walgreens Boots Alliance ($WBA), UnitedHealth Group ($UNH), and Humana ($HUM) will face altered formulary management and potential margin compression on brand-name drugs, though they may benefit from increased generic dispensing fees. This bill has been referred to the Committee on Energy and Commerce and the Committee on Ways and Means. The sponsorship by Rep. Doris O. Matsui (D-CA), a senior member of the Energy and Commerce Committee, indicates moderate legislative momentum. The next step involves committee hearings and potential markups. If it passes committee, it moves to a floor vote. Given the date of referral (March 2026), this bill is in the early stages of the legislative process, but its direct mandate on formularies signals a clear future direction for Medicare Part D.