1 January 2027
Medicare negotiated prices for 2027 take effect
Discounts of 40% to 71% below list price for these drugs, before the rebates drugmakers already pay.
When does Xtandi go off patent?
In the US, generics can launch from 2027. Xtandi is sold by Astellas and Pfizer. Last listed US patent expires August 2027. Sales: Astellas global, ¥960.8B (fiscal year to March 2026).
Xtandi's US exclusivity date is based on patent-expiry estimate. It is estimated from patent expiry rather than a fixed entry date, so it may move as patents are challenged or extended. It is a small-molecule drug, so copies are generics. Generic launches usually take most of the US volume within months.
| Patent or protection | Covers | Expiry |
|---|---|---|
| US 7,709,517 | Enzalutamide itself and the drug product | 13 August 2027 |
| Earlier use patents | Methods of treatment | 24 August 2026 |
| Tablet and newer use patents | Tablets and later uses | 11 September 2033 |
| Latest listed patent | A method of use | 23 February 2037 |
Pfizer, which shares US rights with Astellas, gives 2027 as the US expiry of Xtandi's basic patent, and the FDA lists it to 13 August 2027. Generic makers began challenging the listed patents in August 2024, and Pfizer and Astellas sued them in New Jersey; the cases were still open in Pfizer's 2025 annual report. Later patents on tablets and uses run to 2033 and 2037, and the lawsuits will decide whether any of them delay generics beyond 2027. Sandoz already has final FDA approval. Astellas sells Xtandi outside the US and expects its sales to fall by about ¥50B in fiscal 2026.
Sources: FDA Orange Book data files · Pfizer 10-K 2025 · Astellas FY2025 results
| Year | Astellas, worldwide | Growth |
|---|---|---|
| 2024 | JPY 912.3B | – |
| 2025 | JPY 960.8B | +5% |
Astellas fiscal years run from April to March, so 2025 is April 2025 to March 2026. Fiscal 2024 is fiscal 2025 less the ¥48.5B increase Astellas reports. Net sales as reported, in JPY as the company reports them, so growth is not distorted by exchange rates. Source: Astellas FY2025 results
Approved, waiting to launch The FDA gave Sandoz final approval for generic Xtandi tablets in April 2026, after earlier capsule generics from Actavis, Apotex and Zydus. None has launched: Pfizer and Astellas have sued the filers, and the last listed patent expires in August 2027.
| Company (product) | Stage |
|---|---|
| Sandoz | Tablets: FDA-approved 20 Apr 2026 |
| Lupin | Tentatively approved |
| Actavis (Teva) | Capsules: FDA-approved 14 May 2021, not marketed |
| Apotex | Capsules: FDA-approved 22 Apr 2022, not marketed |
| Zydus | Capsules: FDA-approved 26 Sep 2024, not marketed |
| Ascent | Filed with the FDA; settled 2025, terms confidential |
Checked October 2026. Sources: FDA Orange Book: Sandoz · CancerNetwork: tentative approval · Pfizer 10-Q, Q2 2026
Among past small-molecule drugs facing unrestricted generics, US sales in the first full year after copies arrived were a median 18% of the last full year before (range 0% to 48%, 10 drugs), and 6% by the third year (8 drugs). Where settlements limit generic volumes, as with Revlimid, the decline is slower. Every drug is different: settlements, how many copies launch, and pricing all change the curve. See the erosion benchmarks →
Xtandi was selected for the Medicare Drug Price Negotiation Program. Its negotiated Medicare price takes effect in 2027, 48% below its list price. That is the same year US generics can launch. The discount is measured against list price, before the rebates drugmakers already pay, and applies to Medicare only, so the revenue impact is smaller than the headline number. See every negotiated Medicare price →
Xtandi is 45% of Astellas's 2025 revenue (≈$6.0B of $13.4B). Total revenue ¥2,139.2B, fiscal year to March 2026.
Xtandi is 3.5% of Pfizer's 2025 revenue (≈$2.2B of $62.6B). With Ibrance, Eliquis, Vyndaqel and Prevnar 20, the drugs tracked here add up to 43% of Pfizer's revenue losing US exclusivity by 2035. Eliquis and Xtandi are Pfizer's reported alliance and product revenue ($8.0B, $2.2B).
Bars show each company's tracked drugs as a share of its total 2025 revenue. Xtandi is highlighted.
Discounts of 40% to 71% below list price for these drugs, before the rebates drugmakers already pay.
Generics from Sandoz and others are FDA-approved but have not launched while Pfizer and Astellas pursue patent suits.
Launch still waits on patents: the last listed Xtandi patent expires in August 2027. FDA Orange Book