The most expensive drug in the world is Lenmeldy (atidarsagene autotemcel), a one-time gene therapy for children with early-onset metachromatic leukodystrophy, which lists at $4.25 million in the United States. Two gene therapies follow close behind at $3.95 million each: Fayuvi for Sanfilippo syndrome type A, approved in September 2026, and Kebilidi for AADC deficiency. These are wholesale acquisition costs, the manufacturer's list price before discounts and rebates, as of September 2026.
Every drug that costs more than $2 million is a single treatment for a rare inherited disease, and nearly all are gene therapies, which give a patient's cells a working copy of a faulty gene. The record has been broken five times since 2019: by Zolgensma that year, three times in 2022 alone, and by Lenmeldy in 2024. Medicines taken every year never reach these single prices, but some cost more than $1 million a year, and over a lifetime they can cost more than a gene therapy.
What is the most expensive drug in the world?
Lenmeldy, made by Orchard Therapeutics, is the most expensive drug by list price. The FDA approved it on March 18, 2024, for metachromatic leukodystrophy (MLD), an inherited disease that destroys the protective coating of nerves in the brain and spinal cord and affects about 1 in 100,000 newborns. Doctors collect the child's own blood stem cells, a laboratory adds a working copy of the ARSA gene, and the cells are returned in a single infusion.[1]
Close behind are Fayuvi ($3.95 million), a gene therapy for Sanfilippo syndrome type A, a fatal childhood brain disease, and Kebilidi ($3.95 million), which is infused directly into the brain to treat AADC deficiency, a disorder of dopamine and serotonin production.[2][3] Kresladi, for a rare immune deficiency, was priced at $3.9 million in 2026.[4] Table 1 ranks the drugs whose US list price exceeds $2 million.
| Rank | Drug | Condition treated | Company | US list price | FDA approval |
|---|---|---|---|---|---|
| 1 | Lenmeldy (atidarsagene autotemcel) | Metachromatic leukodystrophy | Orchard Therapeutics | $4.25 million | 2024 |
| 2 | Fayuvi (rebisufligene etisparvovec) | Sanfilippo syndrome type A | Ultragenyx | $3.95 million | 2026 |
| 2 | Kebilidi (eladocagene exuparvovec) | AADC deficiency | PTC Therapeutics | $3.95 million | 2024 |
| 4 | Kresladi (marnetegragene autotemcel) | Leukocyte adhesion deficiency type I | Rocket Pharmaceuticals | $3.9 million | 2026 |
| 5 | Hemgenix (etranacogene dezaparvovec) | Hemophilia B | CSL Behring | $3.5 million | 2022 |
| 6 | Elevidys (delandistrogene moxeparvovec) | Duchenne muscular dystrophy | Sarepta Therapeutics | $3.2 million | 2023 |
| 7 | Lyfgenia (lovotibeglogene autotemcel) | Sickle cell disease | bluebird bio | $3.1 million | 2023 |
| 7 | Zevaskyn (prademagene zamikeracel) | Recessive dystrophic epidermolysis bullosa | Abeona Therapeutics | $3.1 million | 2025 |
| 9 | Skysona (elivaldogene autotemcel) | Cerebral adrenoleukodystrophy | bluebird bio | $3.0 million | 2022 |
| 10 | Roctavian (valoctocogene roxaparvovec) | Hemophilia A | BioMarin | $2.9 million | 2023 |
| 11 | Zynteglo (betibeglogene autotemcel) | Beta thalassemia | bluebird bio | $2.8 million | 2022 |
| 12 | Genglycos | Glycogen storage disease type Ia | Ultragenyx | $2.7 million | 2026 |
| 13 | Itvisma (onasemnogene abeparvovec) | Spinal muscular atrophy, age 2 and older | Novartis | $2.59 million | 2025 |
| 14 | Casgevy (exagamglogene autotemcel) | Sickle cell disease, beta thalassemia | Vertex Pharmaceuticals | $2.2 million | 2023 |
| 15 | Zolgensma (onasemnogene abeparvovec) | Spinal muscular atrophy, under age 2 | Novartis | $2.125 million | 2019 |
The generic names in the table describe how each treatment works. A name ending in -cel is a cell therapy: Lenmeldy, Lyfgenia and Casgevy are made from the patient's own stem cells, modified in a laboratory and given back. A name ending in -vec is a viral vector: Hemgenix, Elevidys and Zolgensma use a modified, harmless virus to carry a new gene straight into the patient's tissues. Both approaches aim to fix the cause of a disease with one treatment, which is why they are priced as a single payment rather than as a yearly bill.
The ranking at the top has changed quickly. Zolgensma held the record from 2019 until August 2022, when three gene therapies raised it in four months, and Lenmeldy set the current mark in March 2024. Each record holder was a one-time treatment for a rare inherited disease, and each raised the ceiling by $0.2 million to $0.75 million.[13][9][5][1]
Why are gene therapies so expensive?
Gene therapy prices are set against the cost of the illness they replace, not against the cost of making them. Before Lenmeldy launched, the Institute for Clinical and Economic Review (ICER), an independent group that estimates what a drug is worth in health gained, put its value-based price at $3.94 million, the highest figure it had ever calculated for any treatment. Orchard priced Lenmeldy above that benchmark, pointing to lower lifetime care costs and fewer working hours lost by parents.[1] Sarepta made the same argument for Elevidys, describing its $3.2 million price as conservative and claiming the therapy would remain cost-effective at $5 million to $13 million.[6]
The other reason is scale. A drug for 1 in 100,000 newborns has only a few dozen possible patients a year in the United States, so each sale must recover a large share of the cost of developing a new drug. Analysts expect Fayuvi to reach peak sales of about $250 million a year despite its $3.95 million price.[2] Rare pediatric disease approvals also earn priority review vouchers, which let the holder speed up a later FDA review and sold for $180 million to $200 million each in 2026. For a small company, a voucher can be worth more than the first years of sales.[11]
How much does Hemgenix cost?
Hemgenix costs $3.5 million for a single infusion. When the FDA approved it on November 22, 2022, it became the most expensive drug in the world, overtaking bluebird bio's Skysona, which had set the record at $3 million two months earlier.[9] It was developed by the Dutch company uniQure and is sold by CSL Behring, and it treats adults with hemophilia B, the rarer form of the inherited bleeding disorder, in which the blood lacks a working clotting protein called factor IX.[5]
Hemgenix uses a modified virus (AAV5) to deliver a factor IX gene to liver cells, which then make the clotting protein themselves. The gene encodes factor IX Padua, a variant first found in an Italian patient with unusually strong blood clotting that differs from normal factor IX by a single amino acid, a change that makes the protein about 5 to 8 times more active.[14][15] In the HOPE-B trial of 54 men, the average number of bleeds per year fell by about 90% over four years, and 94% of patients no longer needed regular factor IX infusions.[15] Because those infusions are themselves costly and lifelong, ICER estimated that Hemgenix would be cost-effective at $2.9 million.[5]
Hemgenix remains the most expensive hemophilia drug. Pfizer's Beqvez, another hemophilia B gene therapy, launched at the same $3.5 million in 2024 but was discontinued in February 2025, with Pfizer citing limited interest from patients and doctors.[16] For hemophilia A, BioMarin's Roctavian lists at $2.9 million.[10]
Zolgensma and Novartis
Zolgensma was the first gene therapy to break the $2 million mark. Novartis launched it in May 2019 at $2.125 million for children under 2 with spinal muscular atrophy (SMA), a genetic disease that destroys the nerve cells controlling movement, and it held the record until bluebird bio's Zynteglo launched at $2.8 million in August 2022.[9] To soften the one-time bill, Novartis offered payers installments over up to five years and outcome-based agreements that tie payment to how well a child responds.[13]
Novartis's most expensive drug is now Itvisma, the same gene therapy injected into the spinal fluid of patients aged 2 and older. It was approved in November 2025 at $2.59 million. Novartis priced it 35% to 46% below what 10 years of ongoing SMA treatment would cost.[12] One such treatment, Spinraza, costs about $900,000 in its first year and about $450,000 a year after that by average wholesale price, and RxBenefits estimates its lifetime cost at more than $10 million.[17]
Most expensive drugs taken every year, and the most expensive pill
Before gene therapies, the title of world's most expensive drug went to medicines taken for life. In 2010 Forbes named Alexion's Soliris, a monoclonal antibody for the rare blood disorder paroxysmal nocturnal hemoglobinuria, the most expensive drug in the world at $409,500 a year.[18] Today the costliest yearly treatments exceed $1 million. By average wholesale price, a pricing benchmark about 20% above the list price, Myalept for generalized lipodystrophy costs about $1.5 million a year, and Zokinvy for progeria and Miplyffa for Niemann-Pick disease type C cost about $1.3 million a year each.[17]
Zokinvy (lonafarnib) is also the most expensive pill, or more precisely capsule, that an ordinary pharmacy can fill. In 2021 Pharmacy Times put its price at $717 for one 50 mg capsule, or more than $1 million a year at a typical dose.[19] It treats Hutchinson-Gilford progeria syndrome, which causes rapid aging in children, and Miplyffa, also an oral capsule, is close behind. No medicine for a common disease comes near these prices, per pill or per year.
List price and what is actually paid
A list price is where negotiations start. BioMarin expected the $2.9 million list price of Roctavian to bring in about $1.9 million after discounts, and it promised to refund insurers up to the full price if a patient did not respond and a prorated share if the effect faded within four years.[10] Abeona offers a partial refund for Zevaskyn if patients need more wound treatment within three years.[8] Refunds of this kind, with the installment plans first offered for Zolgensma, shift part of the risk of an expensive, unproven long-term effect from the payer to the manufacturer.
Taken together, the ranking shows how drug prices have changed with the kind of medicine being sold. The most expensive drugs were once antibodies and pills taken every year for life; they are now single treatments priced to match a lifetime of the care they replace. The record has moved from $2.1 million to $4.25 million in five years, and each new gene therapy for a rare childhood disease is a candidate to move it again.
