Tepezza (teprotumumab-trbw) is Amgen’s infused antibody for thyroid eye disease, the bulging, swelling and double vision that can follow Graves’ disease. Amgen acquired it with Horizon Therapeutics, and it is billed to the medical benefit under HCPCS code J3241 rather than picked up at a pharmacy.
The number most people search for is the price of a vial, and that is the wrong number. Tepezza is dosed by body weight across eight infusions three weeks apart, so the figure that matters is the full course, which lands in the high six figures. This guide does that arithmetic explicitly, states the body weight it assumes, and separates the drug charge from the infusion charge, because those arrive as two different lines on the bill. All figures were researched September 3, 2026.
What Does Tepezza Cost Without Insurance?
Start with the vial. Three independent 2026 sources price one 500 mg single-dose vial within about 2.4% of each other. Medicare’s Part B payment limit file for July 1 through September 30, 2026 pays $379.900 per 10 mg billing unit under J3241, which is $18,995.00 for 500 mg. Drugs.com quotes a cash price of $19,008.45. Amgen’s own list-pricing document, accurate as of June 25, 2026, states a wholesale acquisition cost of $19,451.83 per vial.
Now the course. Amgen’s prescribing information sets the regimen at 10 mg/kg for the first infusion followed by 20 mg/kg every three weeks for seven more infusions, eight total, spanning roughly 21 weeks or about five months. That works out to 150 mg per kilogram of body weight for the whole course. At an assumed body weight of 70 kg (154 lb), the course is 10,500 mg, which is 1,050 of Medicare’s 10 mg billing units.
| Tepezza (teprotumumab-trbw) cost item | Low | Typical | High |
|---|---|---|---|
| One 500 mg single-dose vial, drug only | $18,995.00 (Medicare allowance) | $19,008.45 (retail cash) | $19,451.83 (Amgen list price) |
| One 20 mg/kg dose at 70 kg (1,400 mg, 3 vials) | $53,186.00 (mg administered) | $57,025.35 (3 vials, cash) | $58,355.49 (3 vials, list) |
| Full 8-infusion course, drug only, 70 kg | $398,895.00 (Medicare allowance) | $437,194.35 (23 vials, cash) | $447,392.09 (23 vials, list) |
| Full course by body weight, 60 kg to 90 kg (Medicare allowance) | $341,910.00 | $398,895.00 | $512,865.00 |
| All 8 infusion administrations, facility charge only | $579.88 (Medicare, physician office) | $1,834.16 (Medicare, hospital outpatient) | $8,240.00 (MDsave cash, high end) |
| Medicare Part B coinsurance, full course at 70 kg (20%) | $79,779.00 | $79,779.00 | $79,779.00 |
| Amgen co-pay program (commercial insurance required) | $0 | $0 | $0 |
For a reality check, CMS’s Medicare Part B spending data for 2024 shows $246,465,794.90 spent on Tepezza across 962 beneficiaries and 5,046 claims, which is $256,201.45 per beneficiary for the year and $48,843.80 per claim. Multiply that per-claim average by the eight infusions in a full course and you get about $390,750, which is within 2% of the $398,895 the July 2026 allowance predicts at 70 kg. These are prices that get paid, not sticker numbers nobody meets.
Why the vial math and the milligram math disagree
Medicare pays for milligrams administered. A clinic buys whole vials. At 70 kg a 20 mg/kg dose is 1,400 mg, which requires three 500 mg vials, so 100 mg of every dose is discarded. Across the course that is 23 vials purchased against 10,500 mg given, which is why the vial-based totals run about 10% above the milligram-based total.
That gap is not fictional. Discarded drug from single-dose vials can be billed with a JW modifier, so a self-pay estimate may include it. When you ask for a quote, ask for both numbers: total milligrams and total vials.
The infusion visits are a separate bill
Amgen’s label says to infuse over at least 90 minutes for the first two infusions, and the minimum for later infusions can drop to 60 minutes if tolerated. That maps to CPT 96365 for the first hour plus CPT 96366 for each additional hour.
CMS’s 2026 relative value file assigns 96365 a total of 2.01 non-facility relative value units and 96366 a total of 0.64, which at the $33.4009 conversion factor is $67.14 and $21.38 in a physician office. In a hospital outpatient department the July 2026 addendum pays $217.31 for 96365 and $47.84 for 96366. Across all eight visits that is $579.88 in an office and $1,834.16 in a hospital.
Nobody self-paying will be quoted Medicare’s rate. MDsave’s cash listings for a one to three hour IV therapy infusion range from $300 to $1,030 per visit with a national average of $713, against an estimated national average charge of $1,525. Eight visits at the MDsave average is $5,704.
What Drives the Price
Your body weight. Every kilogram adds 150 mg to the course. At Medicare’s $379.90 per 10 mg, that is about $5,699 per kilogram. A 30 kg difference in body weight changes the course price by roughly $171,000. No other factor on this page moves the number that much.
Vial waste. Because dosing is continuous and vials are 500 mg, most patients pay for drug they do not receive. The only lever is that a lower body weight sometimes drops a dose under a vial threshold.
Where you sit. Identical work costs 3.2 times as much in a hospital outpatient department as in a physician office under Medicare’s own rules for CPT 96365. Independent infusion centers and office-based practices are the cheaper settings, and the drug price does not change between them.
Quarterly repricing. Part B drug payment limits reset every quarter from average sales price data. The $379.90 figure covers July 1 through September 30, 2026 and is based on first-quarter 2026 sales data. The next reset is October 1, 2026, so re-check before you sign anything in the fall.
No generic, no biosimilar. Teprotumumab has no competitor. Unlike drug categories where a biosimilar cuts the price in half, there is nothing cheaper to ask your clinic to stock.
Cash Price vs. Insurance
This is a drug where insurance is not optional in any practical sense. A commercially insured patient can use the Amgen co-pay program and may pay as little as $0 per dose, which Drugs.com lists as covering both the medication and the infusion administration. That program requires commercial insurance and is closed to anyone whose care is paid in whole or part by Medicare, Medicaid, TRICARE, the VA or any other government program.
Under traditional Medicare, CMS’s July 2026 files set beneficiary coinsurance on J3241 at the standard 20%, which is $75.98 per 10 mg unit and about $79,779 across a 70 kg course before supplemental coverage. A Medigap or retiree plan typically absorbs that. The July 2026 hospital outpatient file lists the same $75.98 minimum copayment per unit.
If you are uninsured, there is no published cash price for Tepezza and no manufacturer program that fills the gap. That means the realistic path is coverage, not payment. Enrolling in a marketplace plan, checking Medicaid eligibility in your state, or working through a hospital’s financial assistance policy will move more money than any negotiation on a $19,000 vial.
How to Pay Less
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Get coverage before you get infused. At $400,000 and up, this is the rare treatment where the entire cost strategy is insurance enrollment. If a hospital system is involved, apply for financial assistance in parallel using our hospital charity care guide, and check whether the facility’s policy might cover you with our charity care checker.
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Choose an office or independent infusion center over a hospital outpatient department. Medicare pays $217.31 for the same infusion code a physician office gets $67.14 for. Self-pay quotes track that structure, and the drug is identical either way.
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Demand the estimate broken into three numbers. Total milligrams of drug, number of vials, and the administration codes with the place-of-service. Our fair price checker helps you sanity-check the administration piece, and our guide to itemized hospital bills explains how to force the breakdown after the fact.
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Pull the facility’s posted cash rate before you schedule. Hospitals must publish machine-readable prices for both the drug code and the infusion codes. Our guide to hospital price transparency walks through finding J3241 and CPT 96365 in that file.
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Negotiate the administration, not the drug. The vial price is essentially fixed across sources, but chair time, facility fees and any office visits billed alongside are negotiable. Our guide to negotiating medical bills covers the script and the timing.
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Apply to independent charitable foundations early. Thyroid eye disease funds at disease-specific foundations open and close through the year, and they are the main route for people who do not qualify for the manufacturer program. Apply the day a fund opens rather than waiting for the first bill.
Bottom Line
Budget roughly $399,000 to $447,000 in drug charges for a full eight-infusion Tepezza course at 70 kg as of September 2026, plus $580 to about $8,240 for the eight infusion appointments depending on the setting. Scale the drug figure by about $5,699 for every kilogram of body weight above or below that assumption.
The per-vial price is stable and barely negotiable, and CMS’s own 2024 claims data confirms Medicare pays about $256,201 per Tepezza beneficiary per year. What you can control is the setting, the billing accuracy, and whether you are covered at all. If you are mapping the wider cost of thyroid and eye care, the thyroid test and levothyroxine pages cover the routine side, a cash-pay eye exam covers monitoring, and Vabysmo shows what the other expensive eye injectables run.