Zolgensma, Libmeldy, Zynteglo, and Hemgenix are currently the most expensive drugs in the world, each priced over two million USD per dose.
For many years, pharmaceutical companies have been racing to develop effective treatments for rare diseases or congenital genetic syndromes. With significant investments, expensive raw materials, and complex manufacturing processes, these treatments often come with price tags in the millions of dollars. This is understandable in a relatively high-risk industry where each drug requires immense effort for research and development.
Currently, the record for the most expensive drugs in the world belongs to treatments for spinal muscular atrophy, a genetic disorder affecting white matter, blood disorders, and hemophilia.
Zolgensma
Developed by Novartis and approved in May 2019, Zolgensma treats spinal muscular atrophy and costs 2.1 million USD per treatment, requiring only a single injection. Zolgensma uses a virus to create a healthy copy of the SMN1 gene, which is defective in children with spinal muscular atrophy.
The U.S. Food and Drug Administration (FDA) approved Zolgensma based on clinical trials involving 36 children aged two weeks to eight months. The agency reported that children treated with Zolgensma showed significant improvements in motor development, including head control and the ability to sit up. Zolgensma has been approved in over 38 countries, with approximately 1,000 children receiving this treatment.
In 2018, Novartis initially priced Zolgensma at 5 million USD per treatment. The Institute for Clinical and Economic Review (ICER), an independent organization in the U.S., deemed this price excessively high. On May 24, based on additional clinical data from Novartis and information released by the FDA, ICER concluded that the price of Zolgensma is warranted given its effectiveness.
Novartis leadership argues that the price of Zolgensma is reasonable, stating it is significantly more cost-effective than prolonged treatments that can cost patients hundreds of thousands of dollars each year. The company is also working with insurance providers to alleviate the financial burden on patients.
Libmeldy
In December 2020, the European Medicines Agency (EMA) approved Libmeldy from Orchard Therapeutics, which treats the genetic disorder metachromatic leukodystrophy (MLD), priced at 2.4 million USD.
Typically, children with MLD gradually lose the ability to think, move, and perceive their surroundings. Eventually, they may be unable to walk, swallow, speak, hear, see, or respond to bodily stimuli. Most children with MLD die before reaching the age of five.
Libmeldy provides a healthy gene to produce enzymes in the child’s body. Initially, doctors collect stem cells from the patient’s bone marrow, which can develop into various blood cells, and send them to a laboratory in Italy. There, scientists use a modified virus to insert healthy gene copies containing the enzyme into their DNA.
Finally, the doctor injects the stem cells back into the patient’s bloodstream. The cells migrate to the bone marrow, producing blood cells that can generate the enzyme and function normally.
By March 2022, the drug was further approved by the National Institute for Health and Care Excellence (NICE) in the UK. At that time, the drug was priced at 2.87 million GBP per patient.
Most of the most expensive drugs today are gene therapies. (Image: David Mack).
Zynteglo
Zynteglo is a treatment for beta-thalassemia, approved by the FDA in August 2022. Manufactured by Bluebird Bio, it costs 2.8 million USD.
Beta-thalassemia reduces the amount of hemoglobin and red blood cells in the blood, affecting oxygen delivery. Patients require regular blood transfusions, approximately twice a week.
Zynteglo utilizes a viral vector (a modified virus that is safe for the body) to deliver a healthy gene into the patient’s blood cells, thereby addressing the issue of reduced red blood cells.
According to Bluebird Bio, 89% of Zynteglo users can achieve “transfusion independence”, meaning they do not require blood transfusions for at least 12 months.
Explaining the high price, Bluebird Bio noted that the lifetime medical treatment cost for a patient with beta-thalassemia who does not use Zynteglo and relies on blood transfusions can reach up to 6.3 million USD.
Hemgenix
The record for the most expensive drug in the world currently belongs to Hemgenix. The cost of each treatment is 3.5 million USD. The drug was approved by the FDA in November 2022 based on its safety and effectiveness, assessed in two studies involving 60 adult males.
Hemgenix is a gene therapy for patients with Hemophilia B, a genetic bleeding disorder that prevents the body from producing enough protein to form blood clots. Normally, the clotting process helps prevent excessive bleeding after an injury. If this does not occur, a wound can bleed significantly.
Hemgenix addresses this issue by providing a healthy gene to the body. With this gene, the liver produces more protein, increasing the level of clotting factors in the body, thereby preventing or limiting blood loss.
The most common side effects of the drug include elevated liver enzymes, headaches, flu-like symptoms, and some mild infusion-related reactions.
