Stacey Rifkin-Zenenberg, DO, Pediatric Hematology Oncology, Section Chief of Pediatric Pain and Palliative Care, talks about a drug that brings cholesterol levels to such a low point they are able to prevent some heart diseases.
Can you tell me a little bit about sickle cell anemia? What causes it and who it impacts?
RIFKIN-ZENENBERG: Sickle cell anemia is an inherited hemoglobinopathy, or blood disease, and affects about 100,000 Americans. It is a change in the gene that makes the hemoglobin which carries oxygen in your blood. It affects the cells in the blood and changes the shape of it. As a result, the patients get pain crises, have an increased susceptibility to infection, and can have chronic changes in their organs that end up causing end-organ damage. There are many different treatments that have been given over the years. The first type of treatment has been disease-modifying drugs. The disease-modifying drugs did not cure patients of the disease, but it modified the disease so that it could lengthen the life and increase the quality of life for these patients.
But still not a cure?
RIFKIN-ZENENBERG: Still not a cure. The first cure that came was a bone marrow transplant. Even though there’s 100,000 Americans that have this, there are only a little over 1,000 bone marrow transplants that are performed in this country every year. So, because of that, there was a new therapy that emerged in the last few years called gene therapy. Gene therapy is an experimental therapy, and the emergence of this therapy was because bone marrow transplant requires a patient to have a donor, and it is well-known that about 40 percent of sickle cell patients have donors. So, gene therapy was engineered so that the patient could be their own donor.
Can you walk me through the process of the patient being their own donor?
RIFKIN-ZENENBERG: What you do is take the patient’s own stem cells and either add a gene to their stem cells that would change the mutation they have, or you would edit the mutation in their stem cells. So, in this case, we would add a new gene that would make a new hemoglobin so the patient would become sickle trait, or a carrier of sickle cell disease and not have the disease anymore.
Can you walk me through the process of taking the stem cells and doing a modification? What is that process?
RIFKIN-ZENENBERG: We put an IV in the patient and give them medicine that stimulates their stem cells to come out of the bone marrow. Then, we send the cells to the company to add the gene to their stem cells. They would then be admitted to the hospital and have a few days of chemotherapy because we have to treat them so the stem cells that are left that do have sickle cell in their body are eradicated. We then give them back their own stem cells with the added gene. Once the infusion is infused, it usually takes approximately a month in the hospital, and then they’re discharged.
Why are they in the hospital for that whole time?
RIFKIN-ZENENBERG: We want to watch them because their cells are low and they’re at risk for infection. They also have to have transfusions during that time.
How do you know it’s working?
RIFKIN-ZENENBERG: We know it’s working because we actually test the blood to see what the amount of sickle hemoglobin is. We know that the amount of sickle hemoglobin is the amount that somebody who is a carrier of sickle cell disease has and not someone who has the disease.
How important is this breakthrough in terms of the condition?
RIFKIN-ZENENBERG: It’s extremely important that we have the ability to do gene therapy. Curative options are important because disease-modifying drugs can be used as a bridge to the curative therapies. For the people who don’t have donors for bone marrow transplant, gene therapy may become that option for them. But, gene therapy is still experimental.
How long have you known Razel and how severe was his case?
RIFKIN-ZENENBERG: He had severe sickle cell disease and was admitted multiple times every year. This affected his entire family to the point that they were always on-call to bring him to the hospital. We tried to control his pain at home, but he had to come to the hospital many times for pain management. He had trouble in school because, even though we did what we could, it really does a tremendous amount on the psyche of the patient. Pain itself is really tough to deal with, the psychological part, the spiritual part, and the social part of it. It was a tremendous leap of faith on their side because I was very transparent with them that I didn’t know if this would work. I told them I would take them on this leap of faith and partner with them. He was being admitted at least once or twice a month because we could not get his pain under control. I specifically reached out to the company and tracked them down and told them I needed help with a patient.
Is this a cure? Is Razel cured?
RIFKIN-ZENENBERG: I don’t think that we can say this is a cure yet. There’s still far to go to say that this is a cure. We hope it’s a cure. Right now, he is a year and a half from when we did this, and still remains sickle cell trait. He has no pain at all. The majority of patients in this study are the same as he is. They maintain no pain crises, but maintain their sickle cell trait status.
Can sickle cell be fatal?
RIFKIN-ZENENBERG: Yes, absolutely. At any time in a child’s life or in an adult’s life.
It is a life-threatening condition. That’s why it’s so important we continue to do research and continue to have parents who will agree to things and we keep on doing things like this.
What’s it like when you see Razel now, having treated him from the time he was a baby?
RIFKIN-ZENENBERG: I remember all of the times that he was admitted. I’m proud of him, but I’m also sad because it really has taken a toll on him. This whole experience has been very traumatic for him. If this can be avoided, it would be wonderful because this has been very tough for him to go through. I think that he is ecstatic that he does not have pain, but I think every day he’s very anxious and afraid that it might come back.
Interview conducted by Ivanhoe Broadcast News.
END OF INTERVIEW
This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors; always consult your physician on medical matters.
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