How Much Does Kadcyla Cost With Medicare?
Kadcyla (Ado-Trastuzumab Emtansine) costs an average of $14,515 per Medicare Part D claim, with total Medicare spending of $987.0M in the latest year. A generic version is available, which may reduce out-of-pocket costs.
Key Facts: Kadcyla Cost
- Medicare Part D avg
- $14,515/claim
- Likely Part D tier
- Tier 4-5 (specialty)
- Annual cost/patient
- $117,500
- Generic available
- Yes — Ado-Trastuzumab Emtansine
- Manufacturer
- Genentech/Roche
- Treats
- Cancer
- YoY price change
- -8.2%
Source: CMS Medicare Part D Spending Dashboard. Tier placement inferred from typical formulary norms — confirm with your specific Part D plan.
Kadcyla Medicare Coverage & Out-of-Pocket Cost
Kadcyla is covered under Medicare Part D, with the program paying an average of $14,515 per prescription fill. Kadcyla typically falls on Tier 4-5 (specialty) of standard Part D formularies. Specialty drugs use coinsurance (25-33% of plan-negotiated price), not flat copays. The 2025 Part D annual out-of-pocket cap is $2,000.
Your actual out-of-pocket cost depends on three factors: (1) formulary tier — your plan's specific placement; (2) deductible status — most plans require you to meet up to a $590 deductible (2025) before copays kick in; (3) coverage phase — initial coverage, then the donut hole was eliminated in 2025, replaced by a hard $2,000 annual out-of-pocket cap under the Inflation Reduction Act. Once you hit $2,000 in true out-of-pocket spending, the rest of your Part D drugs are free for the year.
Because generic Ado-Trastuzumab Emtansine is available, the single biggest savings move is asking your pharmacist about generic substitution. Generics typically sit on Tier 1 with copays under $10, vs Tier 2-3 placement for brand-name Kadcyla. Most states allow automatic substitution unless your prescriber writes "dispense as written."
For cash-pay or commercial insurance scenarios, compare prices using GoodRx, SingleCare, or Cost Plus Drugs before filling — discount-program prices sometimes beat Part D copays for lower-cost generics.
Kadcyla is manufactured by Genentech/Roche and prescribed primarily for Cancer. In the most recent Medicare Part D data, 68,000 claims were filed for 8,400 unique beneficiaries, at an average cost of $14,515 per claim. Average annual cost per beneficiary is $117,500.
Year over year, Medicare spending on Kadcyla has decreased by -8.2%. Because a generic version of Ado-Trastuzumab Emtansine is available, patients can often substitute to reduce out-of-pocket costs. Its patent expires 2023-01-31.
Key Data
| Metric | Value |
|---|---|
| Avg Cost Per Claim | $14,515 |
| Total Medicare Spending | $987.0M |
| Total Claims | 68,000 |
| Beneficiaries | 8,400 |
| Generic Available | Yes |
| Year-Over-Year Change | -8.2% |
Other Drugs for Cancer
Frequently Asked Questions
Medicare Part D pays an average of $14,515 per claim for Kadcyla. Kadcyla is typically placed on Tier 4-5 (specialty) of standard Part D formularies. Specialty drugs use coinsurance (25-33% of plan-negotiated price), not flat copays. The 2025 Part D annual out-of-pocket cap is $2,000. As of 2025, total annual out-of-pocket on Part D is capped at $2,000 under the Inflation Reduction Act.
Yes. Kadcyla appears in Medicare Part D claims data, with 8,400 beneficiaries filling 68,000 prescriptions in the latest year. Specific coverage depends on your plan's formulary — call the number on your insurance card or check the plan's Summary of Benefits to confirm prior authorization, step therapy, or quantity limit requirements.
Kadcyla (Ado-Trastuzumab Emtansine) costs an average of $14,515 per Medicare Part D claim, with total Medicare spending of $987.0M in the latest year. A generic version is available, which may reduce out-of-pocket costs.
Yes. A generic version of Ado-Trastuzumab Emtansine is available, which typically costs 80-95% less than brand-name Kadcyla. Ask your pharmacist about generic substitution — most state laws allow automatic substitution unless your prescriber writes "dispense as written."
Medicare beneficiaries cannot use manufacturer copay cards (anti-kickback statute), but several options exist: (1) Apply to charity copay foundations like the PAN Foundation, NeedyMeds, HealthWell Foundation, or Patient Advocate Foundation — many cover cancer drugs; (2) Ask your prescriber about therapeutic alternatives in the same drug class that may be on a lower tier; (3) For some drugs, paying cash via GoodRx or Cost Plus Drugs can beat your Medicare copay — always compare before filling; (4) If your income is below 150% of the federal poverty level, you may qualify for the Medicare Extra Help (Low-Income Subsidy) program, which reduces Part D costs to near-zero.
Kadcyla is manufactured by Genentech/Roche. The FDA application number is BLA125057.
Kadcyla (Ado-Trastuzumab Emtansine) is primarily prescribed for Cancer.
Medicare Part D spending on Kadcyla has decreased -8.2% year over year. Total program spending reached $987.0M in the latest reporting year.
Kadcyla (Ado-Trastuzumab Emtansine) costs an average of $14,515 per Medicare Part D claim, with total Medicare spending of $987.0M in the latest year. A generic version is available, which may reduce out-of-pocket costs.
The data source behind this answer is CMS Medicare Part D Drug Spending data. Every figure on the page traces back to that source; the methodology page describes the inputs and the refresh cadence in full detail.
A practical caveat: the headline answer above reflects the most recent CMS Medicare Part D Drug Spending data vintage; underlying data is often revised for months after first publication, and the right reference for any specific decision is whichever vintage is current at the time of the decision. The as-of date is stamped on every page.
Source: CMS Medicare Part D Spending, 2026.