The United States Federal Drug Administration (FDA) has just approved a new treatment for a rare blood-clotting disease that comes at a high price.
It costs $3.5 million per dose, making it the most expensive drug in the world.
At first glance, the price is startling, but a recent analysis of the drug’s cost-effectiveness suggests that this is a relatively “fair” price for what the treatment achieves — at least in the US.
The medicine, called Hemgenix, is a gene therapy treatment for hemophilia B, a rare genetic disorder that causes blood to clot less quickly. The most serious symptoms include spontaneous and repeated bleeding episodes that are difficult to stop.
Hemophilia B tends to be more common in men than women, and while an exact number is difficult to pinpoint, it is estimated that nearly 8,000 men in the United States currently have the lifelong disease.
The main drug currently used to treat hemophilia B in the US gives patients a much-needed clotting factor, but the lifetime cost of treatment is high. Patients with severe symptoms require a routine and expensive treatment regimen that can become less effective over time.
Today, researchers estimate the lifetime cost of 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 anywhere else in Europe, but still add up to tens of millions of dollars per patient over their lifetime.
Hemgenix, on the other hand, is a one-time intravenous product that is administered in a single dose at a fraction of the price. The product is transported into the body via a virus-based vector engineered to deliver DNA to target cells in the liver. This genetic information is then replicated by cells, spreading the instructions for a clotting protein known as factor IX.
Two studies so far have tested the effectiveness and safety of Hemgenix. In a study of 54 participants with severe or moderate hemophilia B, researchers found elevated levels of factor IX activity, reducing the need for routine replacement therapies currently available to patients.
After receiving gene therapy, the rate at which patients developed uncontrolled bleeding dropped by over 50 percent compared to their baseline rate.
Side effects included headaches, flu-like symptoms and liver enzyme elevations, all of which should be carefully monitored by doctors going forward.
“Gene therapy for hemophilia has been on the horizon for more than two decades. Despite advances in treating hemophilia, the prevention and management of bleeding episodes can impact patients’ quality of life,” said Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research.
“Today’s approval offers a new treatment option for patients with hemophilia B and represents an important advance in the development of innovative therapies for patients suffering from a high burden of disease associated with this form of hemophilia.”
It’s not yet clear if this gene therapy is a cure for hemophilia B, but early results are promising.
For serious but rare conditions like 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.
The US government’s incentives to encourage scientific research are a useful way to spur innovation in rare diseases that would otherwise fall by the wayside, but this policy is a double-edged sword.
It also means that the US market bears the costs of supporting drug monopolies while other nations that restrict drug prices benefit from international research.
Today, the US pays two to six times more for prescription drugs than other countries around the world.
The previous record holder for the most expensive drug was another “one-shot” form of gene therapy used to treat spinal muscular atrophy. At an estimated $2 million per course, it also sparked heated debate about how drug companies fund their businesses.
While many drugmakers have used orphan drug status to create drug monopolies over the past few decades, this latest product could be a case where the policy could work, at least for some people.
The upfront costs are certainly huge, but for those lucky enough to have a supportive insurance company, Hemgenix could save millions in medical expenses and improve life in immeasurable ways.
The European Medicines Agency and their counterparts in the UK and Australia are also now reviewing the use of gene therapy treatment.
It will be interesting to see how much drugmakers are allowed to charge for Hemgenix in other parts of the world.