KFF puts the 18-month cost of the Medicare GLP-1 Bridge between $1.3 billion and $10 billion

The nonpartisan research group KFF estimates that Medicare's GLP-1 Bridge demonstration could cost between $1.3 billion and $10 billion over its 18-month run, depending on how many of the nearly 4 million eligible beneficiaries take part ^[1]. The Trump administration has not released its own cost estimate for the program ^[1].

The spread between the low and high ends is enormous — roughly eightfold — because almost everything depends on participation. For scale, KFF says Medicare Part D spending on prescription drugs was $181 billion in 2025 ^[1]. Even the top of KFF's range would amount to a small share of that annual total, but it would be spread across a year and a half rather than a single year.

What the Bridge is

Medicare is barred by law from paying for drugs used specifically for weight loss, so CMS built the Bridge as a short-term demonstration that sits outside normal Part D coverage ^[1][2]. It launched July 1, 2026 and now runs through December 31, 2027, after CMS extended it from an original end date of December 31, 2026 ^[2].

Eligible beneficiaries pay a $50 monthly copay for covered obesity medicines: all formulations of Wegovy (semaglutide) and Foundayo (orforglipron), plus the KwikPen formulation of Zepbound (tirzepatide) ^[2]. A prescriber must submit a prior authorization attesting the drug is for weight reduction and maintenance, and that the person meets one of three clinical tiers: a BMI of 35 or higher; a BMI of 30 or higher with heart failure with preserved ejection fraction, uncontrolled hypertension, or chronic kidney disease stage 3a or above; or a BMI of 27 or higher with pre-diabetes, a previous heart attack, a previous stroke, or symptomatic peripheral artery disease ^[2]. People with type 2 diabetes or sleep apnea are not eligible for the Bridge, because Part D plans should already cover GLP-1s for those diagnoses ^[1].

Early uptake is running ahead of expectations

Less than two months in, CVS and Walgreens each told NPR they had filled roughly 100,000 Bridge prescriptions, with CVS citing more than 100,000 as of mid-August ^[1]. Walmart did not give a number but said Bridge prescriptions have been processed at more than 5,000 Walmart and Sam's Club pharmacies and are growing week over week ^[1].

CMS did not give NPR participation figures, though CMS Administrator Mehmet Oz said in a July 29 video on X that 250,000 beneficiaries had signed up ^[1]. It is not clear whether those people had prior authorizations approved, which is required before a Bridge prescription can be filled ^[1].

Jeremy Shane of the USC Leonard D. Schaeffer Institute estimated that if the two chains account for about 200,000 prescriptions and other pharmacies account for perhaps twice as many again, that would be "somewhere between 5% and 10% of the eligible population in just a short period of time" ^[1]. Walgreens chief pharmacy officer Rick Gates said stores stocked extra Wegovy, Zepbound and Foundayo ahead of the July launch and have not hit supply problems, and that about half of Walgreens' Bridge patients had never taken a GLP-1 before ^[1].

Why it matters for patients

The cost question is not academic. The Bridge is a temporary demonstration, and how much it ends up costing — and how many people use it — is the kind of evidence that tends to shape whether and how Medicare covers obesity drugs after the program ends. Higher-than-expected uptake cuts both ways: it shows real demand, but it also pushes the bill toward KFF's upper estimate.

For context on the baseline, Medicare already recorded 21.8 million GLP-1 claims and $27.5 billion in gross spending (before rebates) in 2024 for approved non-obesity uses ^[2]. Net spending after rebates would be lower ^[2].

It is also worth noting what the Bridge does not do: it does not change the underlying statute, and it excludes some people with serious conditions from its $50 copay, as NPR has reported separately ^[1].

What happens next

The Bridge is scheduled to end December 31, 2027 ^[2]. The broader BALANCE Model, which would have expanded Medicare Part D coverage starting in January 2027, has been indefinitely delayed; the Medicaid side of BALANCE began rolling out May 1, 2026 with implementation continuing until January 1, 2027, and ends December 31, 2031 ^[2]. Separately, semaglutide was selected for Medicare drug price negotiation in 2025, with a negotiated price set to take effect in 2027 ^[2].

Whether CMS will publish its own cost figures for the Bridge is not yet known.