Two widely prescribed cancer drugs are among the medications Medicare has negotiated new prices for under the second round of its drug price negotiation program, with the lower prices scheduled to take effect at the start of 2027. Xtandi, used mainly for advanced prostate cancer, and Ibrance, used for certain forms of breast cancer, both carry list prices running into the thousands of dollars a month, making them two of the more closely watched names on this year’s list.
The negotiation authority comes from the same 2022 law that redesigned Part D’s cost-sharing structure, and this second round marks the first time the program has reached into oncology in a significant way.
The first round of negotiated prices, which took effect in 2026, covered ten drugs selected mostly for their high total spending across the Medicare population — blood thinners, diabetes medications and a handful of other widely used treatments. The second round was chosen using the same criteria, but the mix of drugs that qualified this time skews more heavily toward specialty and oncology medications, reflecting how much of Part D’s total spending is now concentrated in a relatively small number of high-cost prescriptions.
What Changes for Xtandi and Ibrance on January 1
The Centers for Medicare & Medicaid Services negotiated new maximum fair prices for 15 Part D drugs in this second round, with Xtandi and Ibrance both on the list alongside other high-cost medications. Xtandi carries a list price of more than $14,500 a month and Ibrance more than $16,500 a month, and both are used for cancers that disproportionately affect older adults. The negotiated prices apply to what Medicare drug plans pay for the medications starting January 1, 2027, which in turn shapes what plans charge enrollees through their formulary tiers and cost-sharing rules.
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The Rest of the Second-Round List
Xtandi and Ibrance are not the only cancer treatments affected. The American Society of Clinical Oncology counts four anti-cancer drugs on the 2027 negotiation list, also including Pomalyst, used for multiple myeloma, and Calquence, used for certain blood cancers. The other eleven drugs on the list cover conditions ranging from diabetes to autoimmune disease, meaning the second round reaches a broader share of Part D enrollees than the first, which focused more narrowly on a handful of blockbuster medications.
How Much the Prices Are Actually Falling
Reductions vary by drug. Across all 15 medications on the list, AARP’s tracking of the program puts the average cut at roughly 44 percent off list prices, with individual discounts ranging from about 38 percent to more than 80 percent depending on the medication. AARP estimates the second round will produce roughly $685 million in combined out-of-pocket savings for the Part D enrollees who take these drugs once the new prices take effect.
What a Negotiated Price Does and Doesn’t Guarantee
A lower negotiated price changes what Medicare and its drug plans pay manufacturers; it does not by itself set what an individual enrollee owes at the pharmacy counter. That amount still depends on which formulary tier a plan assigns the drug, where the enrollee stands relative to the year’s deductible, and how close they are to the annual out-of-pocket cap that governs Part D spending starting in 2027. For someone prescribed Xtandi or Ibrance, the negotiated price is likely to lower total plan and program costs, but the personal savings show up through those existing cost-sharing rules rather than as a direct discount at checkout.
That gap between a negotiated list price and an individual’s actual bill is one reason patient groups have urged plans and pharmacies to be explicit about how the new prices are reflected in 2027 coverage documents. A patient switching plans during this fall’s enrollment period has an added reason to check whether a specific cancer drug’s formulary tier changes along with its negotiated price, since a lower ceiling on what Medicare pays does not automatically move a drug to a cheaper tier.
When a Negotiated Price Doesn’t Reach the Copay
A headline price cut on a specialty cancer drug rarely translates cleanly into a smaller bill at the pharmacy, since formulary tier placement, deductible timing and appeal rights all sit between the negotiated price and what an enrollee actually pays. Someone managing a new cancer diagnosis on top of a plan’s paperwork has little bandwidth left to track where a specific drug falls in that chain.
The Medicare Cost & Coverage Protection Kit is a 10-page kit covering the prior-authorization appeal steps and the new Part D out-of-pocket cap, plus a medication and cost tracker for following spending drug by drug.
Read the full kit at The Medicare Cost & Coverage Protection Kit.
This article was reported and written with AI assistance and reviewed by The Financial Wire editorial team.
David M. Keller is a finance writer based in Columbus, Ohio, covering personal finance and consumer-focused economic topics. He earned his degree in journalism from Ohio University and began his career reporting on local business and economic trends for a regional media outlet. Since then, he has contributed to a variety of online publications, focusing on clear, practical coverage of topics such as cost of living, debt, and everyday financial decision-making.
