Kadcyla Average Wholesale Price per Vial
Kadcyla (ado-trastuzumab emtansine), used for HER2-positive breast cancer, comes in single-dose vials of 100 mg or 160 mg. The average wholesale price (AWP) is about $11,000 per 100 mg vial and $17,600 per 160 mg vial, based on U.S. pricing data as of late 2023. These figures exclude discounts, rebates, or patient assistance, which can lower net costs significantly.[1]
Dosing typically requires 3.6 mg/kg IV every 3 weeks (e.g., 280 mg for a 70-78 kg patient), so per-treatment costs range from $20,000-$30,000 before adjustments.[2]
How Much Patients Actually Pay
Out-of-pocket costs vary widely:
- With commercial insurance: Often $0-$500 per dose after copays, thanks to manufacturer coupons from Genentech.
- Medicare Part D: Average $100-$1,000 monthly, capped at $2,000/year in 2025 under the Inflation Reduction Act.
- Uninsured: Full list price applies, but Genentech's assistance programs cover most for eligible patients earning under $100,000/year.[3][4]
| Factor | Impact on Cost |
|--------|---------------|
| Insurance type | Commercial: lowest copays; Medicare: benefit design caps exposure |
| Body weight | Higher weight = more vials (e.g., >100 kg may need two 160 mg vials) |
| Site of care | Hospital outpatient: 20-50% higher than physician office due to facility fees |
Factors Driving High Costs
List prices haven't changed much since FDA approval in 2013, but inflation and lack of competition keep them elevated. No biosimilars are approved yet; patents on the antibody-drug conjugate last until at least 2027, with some formulation patents to 2033.[5] Genentech (Roche) faces ongoing litigation from competitors like Pfizer over these protections.
Cheaper Alternatives and Comparisons
- Tukysa (tucatinib) + Herceptin + Xeloda: Similar efficacy in some trials; monthly cost ~$15,000-$20,000, often lower net after rebates.[6]
- Enhertu (fam-trastuzumab deruxtecan): Newer ADC rival; list price ~$13,000 per 100 mg vial, but real-world costs comparable after negotiations.[7]
- Generic capecitabine or tamoxifen: Much cheaper (~$100/month) but less targeted for HER2+ cases.
Switching often depends on biomarkers and prior treatment failure. Tools like GoodRx show current pharmacy prices starting at $10,500 for 100 mg vials with coupons.[8]
Patent Status and Future Price Drops
Key U.S. patents expire 2027-2033; check DrugPatentWatch.com for updates on challenges.[5] First generics/biosimilars unlikely before 2028, potentially halving prices like with Herceptin.
[1]: IBM Micromedex RED BOOK (2023 pricing).
[2]: Kadcyla prescribing information, Genentech.
[3]: Genentech Access Solutions patient data.
[4]: CMS Medicare Part D reports.
[5]: DrugPatentWatch.com
[6]: Tukysa WAC pricing, Seagen.
[7]: Enhertu pricing, Daiichi Sankyo/AstraZeneca.
[8]: GoodRx.com (real-time quotes).