For many, many years we've been hearing about gene therapy - the chance that we can get into people's DNA and fix it to resolve problems and fix disease. In a recent piece in Science, Stuart Orkin and Philip Reilly discuss what finally achieving success might mean:
Imagine a young man with hemophilia A who no longer has to self-administer factor VIII replacement; an individual with sickle cell disease who is free of chronic pain and intermittent crises; a girl functionally blind since the age of 5 who can now see; or a baby rescued from a fatal, inherited neurodegenerative disease. For decades, gene therapy has tantalized us with such futuristic scenarios. However, these goals are now coming into focus, and it is the time to consider some of the consequences of success.
As they report, gene therapy has been forty-four years in the making. But gene therapy, which has cost billions of dollars in research and development, is different from the traditional pharmaceutical market. For one thing, most diseases which are the focus of gene therapy research are relatively rare. Most of these conditions affect children. In addition, gene therapy is more like a procedure than a drug. You perform it once, and potentially achieve a lifetime cure. There's no way that, like many pharmaceutical products, profits can be made on volume.
It's important to note that at this time, we still don't have a lot of promising results in human subjects. But we're getting close - close enough that it's best we consider how we might pay for this now, rather than wait until it's here and we all start fighting about it.
We may expect that prices for gene therapy might approach previously unseen amounts. The only gene therapy currently approved for use in Europe is Glybera. It treats lipoprotein lipase deficiency, a rare illness. It's now priced at more than $1 million per patient, even though, as the authors point out, its efficacy is not without doubt.
This may seem ridiculously high, but it's not. Organ transplants can run that high, and they sometimes offer less of a cure than gene therapy might. Even bone marrow transplant can cost more than $500,000, and we do that all the time. But when it comes to therapies that aren't procedures, we often balk. The fights over Sovaldi, which was still arguably cost-effective compared to other treatments, might give us an inkling of what's to come.
The authors offer some ideas on where to start. First, they present some estimates on the current cost of managing genetic disorders. Cystic fibrosis costs almost $6 million per patient over a lifetime. Gaucher disease about $5 million, sickle cell disease $1 million, and Hemophilia A between $5 and $10 million.
They also suggest we consider the modality of the specific gene therapy. If it's as intensive as bone marrow transplant, it may be priced similarly. Development costs must be considered, which are likely similar regardless of the prevalence of the disease being treated. That prevalence is its own factor, however. The price will likely have to be higher when the disease is rarer.
Further considerations involve how much it costs to produce the therapy, and, of course, what outcome is expected. A full, definitive cure may be worth quite a bit.
Clearly, different countries will make these determinations in varying ways. The United States, more than any other, lets the market decide what it will pay. That doesn't always turn out well. The authors suggest the following instead:
First, very expensive gene therapies with large up-front payments should require that the burden of retreatment be borne by the drugmaker or its successors... Second, some reasonable portion of the economic benefits that under the Orphan Drug Act flow to companies that develop therapies for “orphan” disorders might be redirected to reducing the price of the drug, perhaps by greatly reducing the pricing of copays... Third, the U.S. National Academy of Medicine (or a similar body) should commission a study to explore new methods to streamline the regulatory process for developing genetic and perhaps other therapies for ultrarare disorders.
These aren't definitive solutions, but they're a good place to start. It's better that we have this discussion before decisions have to be made, rather than after. Go read their article.