The United States Federal Drug Administration (FDA) has approved a new treatment for a rare blood clotting disorder.
Each dose will cost US$3.5 million, making it the most expensive drug anywhere in the world.
At first glance, the price is staggering, but recent analyzes of the drug’s effectiveness show that it is a relatively “fair” price for what the treatment achieves. – at least in the US.
The drug, Hemgenix, is a gene therapy tool for hemophilia B, a rare genetic disorder that causes reduced blood clotting. The most serious symptoms include spontaneous and recurrent episodes of bleeding that are difficult to stop.
Hemophilia B is more common in men than women, and although exact numbers are hard to come by, estimates suggest that about 8,000 men in the United States currently suffer from the disease in their lifetime.
The main drug currently used to treat hemophilia B in the United States provides patients with a much-needed clotting factor, but its lifetime treatment costs are high. Those with severe symptoms require a regular and expensive treatment regimen that may begin to diminish over time.
Today, researchers estimate the lifetime costs to adults for each patient with moderate to severe hemophilia B to be approximately $21 to $23 million. Treatment costs in the UK are cheaper than in the US or elsewhere in Europe, but run into tens of millions of dollars over the lifetime of each patient.
Hemgenix, on the other hand, is a single-dose intravenous product at a fraction of the cost. The product is delivered into the body via a viral-based vector designed to deliver the DNA to target cells in the liver. This genetic information is then replicated by cells and releases the instructions for a clotting protein known as Factor IX.
Two studies have so far tested the effectiveness and safety of Hemgenix. In a study of 54 participants with severe or moderate hemophilia B, researchers found increased levels of Factor IX activity, reducing the need for regular replacement therapies currently available to patients.
After receiving the gene therapy, the rate of uncontrolled bleeding in patients decreased by more than 50 percent compared to their baseline.
Side effects included headaches, flu-like symptoms and liver enzyme elevations, all of which should be closely monitored by doctors.
“Gene therapy for hemophilia has been on the horizon for more than two decades. Despite advances in the treatment of hemophilia, preventing and treating bleeding episodes can have a negative impact on people’s quality of life,” said FDA Director Peter Marks. Center for Biology Evaluation and Research.
“Today’s approval provides a new treatment option for hemophilia B patients and represents an important advance in the development of innovative therapies for those living with the high disease burden associated with this form of hemophilia.”
It is not yet clear whether this gene therapy treatment is a cure for hemophilia B, but early results are promising.
For serious but rare diseases such as hemophilia B, the FDA has a special designation to encourage medical research. For example, Hemgenix is classified as an “orphan drug” because it will only treat a small number of patients.
As part of this designation, Hemgenix manufacturer CSL Behring has exclusive rights to the US market for the next seven years.
U.S. government incentives to spur scientific research are a useful way to spur innovation in rare diseases that would otherwise fall by the wayside, but the policy presents a double-edged sword.
It also means that the US market bears the costs of supporting drug monopolies, while other countries that impose drug price caps benefit from international scrutiny.
Today, the United States pays two to six times more for prescription drugs than the rest of the world.
The previous record holder for the most expensive drug was another “one shot” form of gene therapy for the treatment of spinal muscular atrophy. At around $2 million per course, it has sparked heated debate about how drug companies should fund their ventures.
While many drug manufacturers have used orphan drug status over the past few decades to create drug monopolies, this latest product may be a case where the policy may work, at least for some people.
The upfront costs are certainly huge, but for those lucky enough to have a supportive insurance company, Hemgenix can save millions in medical costs and improve their lives immeasurably.
The European Medicines Agency and its drug regulatory counterparts in the UK and Australia are also reviewing gene therapy treatments for use.
It will be interesting to see how much drug manufacturers are allowed to charge for Hemgenix in other parts of the world.