The Cost of Gene Therapy in Treating Sickle Cell Disease

Peter Salgo, MD: What does it cost to treat a patient with sickle cell disease throughout his or her life? Compared to the cost, potentially, of gene therapy, or transplant?

Sophie Lanzkron, MD, MHS: There is a wide range, and I think that’s the other key piece of this is that there are some people who can go through their lives with minimal costs, and there are some people who have just outstanding costs. There was a press release, I think it was from AHRQ [Agency for Healthcare Research and Quality] that talked about billions of dollars that were spent from 2016, that the admission rates have gone up 40% in the last few years. And so, we do know that there is a large amount of cost from acute care utilization associated with this disease. But it’s not everyone, right? There are patients who rarely seek care. They see their primary care doctor once a year, they see their hematologist once a year, and they do well. And I think our responsibility is to identify those people for which these expensive therapies are most appropriate.

Biree Andemariam, MD: I 100% agree. There’s also the cost that’s not measurable in dollars.

Jane Hankins, MD, MS: Yes, that’s right.

Biree Andemariam, MD: And that’s the cost to quality of life of the individual living with sickle cell disease and their caregivers. And some of this is quantifiable. Lost days of school and progression towards one’s goals, academically, if you’re a child born with sickle cell disease. Being a parent of an individual with sickle cell disease and having some missed days from work. Some of that is quantifiable. And if we could change the course of this disease and we could have kids born with sickle cell disease have some curative intent, or curative therapy, and they could live disease-free, they would then have more productive lives. And that would feed back into our economy.

Peter Salgo, MD: You know what’s exciting to me? We’re sitting at a table. We are talking about sickle disease, and in this conversation the word “cure” has actually popped up.

Biree Andemariam, MD: Yes, right.

Peter Salgo, MD: And this is a first. This is a first. I didn’t think within my clinical career I would ever see this. So, when you say it’s exciting, I agree with you.

Elliot Vichinsky, MD: I think it’s very exciting. But I’ve got to tell you: I’ve been around a long time and I’ve heard “cure” a long time. The cyanate, the urea, there are a lot of drugs that were coming out. And so what I’m concerned about, I do think these are disease-modifying therapies. But most of the patients don’t get the comprehensive care that will sustain their life that’s available. And so, it isn’t a choice that I’ve heard, “Well, if we can’t provide care for them, let’s give them these therapies.” There are a lot of standard medical care techniques that will provide improvement in outcomes and quality of life, as well as survival. That should be the infrastructure as they make decisions. So, we have to have those things, too.

Jane Hankins, MD, MS: I completely agree, and I made a note in here about supportive care. That made a difference in children with ALL [acute lymphocytic leukemia]. Patients with ALL today have a 90% survival rate, right? A lot of that is supportive care.

Peter Salgo, MD: Okay. Well let me take the reductio ad absurdum, if I may, which is: let’s presuppose I have a patient with severe SS [sickle cell] disease. Right? This patient gets tremendous care, is integrated into the system, gets everything that we can throw at this disease. With that, what’s the estimated lifespan?

Biree Andemariam, MD: I don’t know that we have an exact number, but Elliot said earlier that in his opinion this could be into the 60s.

Elliot Vichinsky, MD: Well there are risk factors for each patient. If you look at aggregate data, the sad news is the survival rate is 40 years, versus the 60-year survival rate that was reported in London and some of the centers in the United States.

But each individual patient has risk factors. So, you could have a child who’s never had any problems, doing well, and then they have a catastrophic stroke, and then their care, and now we can keep them alive, but then they go on for a long time. So, I think with supportive care the lifespan as an aggregate group would be around 60 years of age if it was done correctly. And not quality of life.

Jane Hankins, MD, MS: Not quality of life, correct.

Elliot Vichinsky, MD: No. I mean that they may survive longer, but they’re still going to have multi-organ failure.

Peter Salgo, MD: There are 2 ways to take the next question, which is, is the incremental life expectancy from 60, to less than whatever the average life expectancy in America is: approximately the mid 80s. But I agree, it’s quality. They added 20 years. Is that 20 years on a cost-effective basis, and boy that’s a tough question, with the money, transplant, or a gene therapy?

Sophie Lanzkron, MD, MHS: It depends, right?

Sophie Lanzkron, MD, MHS: Right. Such morbidity associated with this disease, is that right?

Peter Salgo, MD: Let’s modify life expectancy by quality of life, which one can suppose over the years with microinfarct, with everything else even with the best of care, gets worse and worse and worse. So even if you’re aged 60, 70, 80, your life is getting worse.

Jane Hankins, MD, MS: Yes.

Elliot Vichinsky, MD: Dialysis. The unemployment.

Peter Salgo, MD: So that costs money too.

Jane Hankins, MD, MS: Yes.

Peter Salgo, MD: So, even if you increase life expectancy, you’re increasing cost. And to some degree, because of increased life expectancy, you’re increasing cost of care. Right? The cost of care of sickle specifically.

Biree Andemariam, MD: If you didn’t give them curative therapy.

Peter Salgo, MD: That cost needs to be bundled in. I’m trying to get a way to balance this. My personal sense is, if you can make the cost of transplant or gene therapy rational, whatever rational may be, as defined that the cumulative cost going out over the next 40, 50, 60 years, doesn’t it favor early intervention curatively?

Biree Andemariam, MD: Yes, I get it now, yes.

Jane Hankins, MD, MS: And I think what we need is good simulation, good cost-effectiveness analysis that we haven’t done.

Elliot Vichinsky, MD: If the study proves to do what we think they are, there’s no question in my mind.

Jane Hankins, MD, MS: Of course.

Elliot Vichinsky, MD: And I would intervene very early in life. So, the question about cost in a lot of ways is a little bit upsetting for me because we have not done anything for this disease. If these drugs really worked the way we expect them, that would be a no-brainer for me to do all of those therapies.

Transcript edited for clarity.