Medicare Part D spending is highly concentrated: a relatively small set of drugs drives a large share of the total. Looking at the latest CMS data (data year 2023), three therapeutic stories stand out.
The categories driving spend
| Category | Headline drugs | Why it is big |
|---|---|---|
| Anticoagulants | Eliquis, Xarelto | Huge, aging patient populations on daily therapy |
| Diabetes / GLP-1 / SGLT2 | Ozempic, Jardiance, Trulicity, Farxiga | Large populations plus high per-unit cost; fast growth |
| High-cost biologics | Humira pen, Revlimid | Very high per-unit price, smaller populations |
The blood thinner at the top
Eliquis alone accounted for $18.3B in 2023 — by far the single largest line. It serves nearly 4 million beneficiaries at a modest $9.74 per dosage unit; the scale, not the unit price, makes it #1.
The GLP-1 surge
The fastest-growing big drug was Ozempic, where spending nearly doubled (+98.7% year over year). The GLP-1 class — Ozempic and Trulicity — plus the SGLT2 inhibitors Jardiance and Farxiga, reflects a structural shift in how diabetes and related conditions are treated.
Concentration matters for policy
Because spending is so concentrated, a handful of negotiations or patent expirations can move the program’s total. That concentration is exactly why these drugs were early targets of Medicare drug price negotiation.
Browse the full biggest total spend ranking or the A–Z drug index. These are aggregate program figures, not the price you pay, and not medical or pricing advice.
Source: CMS Medicare Part D Spending by Drug, data year 2023, U.S. public domain.