Launch of Stem Cell Therapy Trial Offers Hope for Patients with Inherited Blood Disorder

Pictured: Isabelle Rivière and Michel Sadelain

Isabelle Rivière (left), Director of the Cell Therapy and Cell Engineering Facility, and Michel Sadelain, Director of the Center for Cell Engineering

Memorial Sloan Kettering Cancer Center will begin evaluating a new stem-cell-based gene therapy for patients with the inherited blood disorder beta (β)-thalassemia. The clinical trial is the first to receive US Food and Drug Administration approval to treat this disease with genetically engineered cells.

This potential new treatment is a culmination of more than two decades of research led by Memorial Sloan Kettering investigators. If the trial proves to be successful, the treatment could offer hope of a cure for patients with this severe blood disease, as well as related conditions such as sickle cell disease.

“Launching this trial is a major milestone for all the people at Memorial Sloan Kettering and international collaborators who have contributed to this work,” says Michel Sadelain, who leads the Center for Cell Engineering. “Our team was the first to show this approach was possible in disease models, and I’m thrilled to be able to finally start offering this potentially curative therapy to patients.”

A Hereditary Blood Disorder

β-thalassemia is found in people of Mediterranean, Asian, and African descent. It is characterized by the inability of red blood cells to make a protein called β-globin. In sickle cell disease, a related disorder affecting the same gene, the red blood cells make an abnormal form of β-globin.

Together, β-thalassemia and sickle cell disease are the most common, severe hereditary blood disorders worldwide, with several million people affected and more than 50,000 born with these conditions every year.

The current treatment for β-thalassemia is a lifetime of regular red blood cell transfusions, which are lifesaving but fraught with serious secondary complications. Bone marrow or stem cell transplants can offer a cure, but more than three-quarters of patients are unable to find a matched donor.

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Hope for Patients

The trial, which is now enrolling patients, is led by Farid Boulad, a pediatric hematologist-oncologist and transplant specialist, together with Isabelle Rivière, Director of Memorial Sloan Kettering’s Cell Therapy and Cell Engineering Facility, and Dr. Sadelain.

In the trial, patients will have their blood stem cells extracted from circulating blood — a process in which the stem cells are filtered out of the patients’ blood while their other blood cells are returned to them. Investigators will then use a vector to introduce a functional version of the β-globin gene into patients’ stem cells. Vectors are disabled viruses that cannot replicate but efficiently shuttle their genetic cargo into host cells.

“Memorial Sloan Kettering has one of the finest cell therapy facilities in the world to expand and engineer patient cells for clinical studies in patients with cancer and genetic disorders,” says Dr. Rivière.

After receiving a low dose of chemotherapy to suppress the body’s natural production of blood cells, patients will have their own genetically engineered stem cells infused back into them.

“Treating a genetic defect with a reconstructed gene is something we dreamed about in medical school,” says Dr. Boulad. “The fact that it is now a reality is amazing. It is the holy grail of the treatment of genetic disorders.“

The trial will eventually be extended to patients at other institutions, including the National Institutes of Health and the University of Washington. Dr. Sadelain’s group is coordinating with investigators in Italy and Greece and throughout Asia — areas where β-thalassemia is much more prevalent — to offer the treatment to patients there as well.

Only a small handful of diseases are currently treated with this type of gene-transfer therapy, and all but one of them are rare immune disorders. If the treatment proves effective, β-thalassemia would be by far the most common condition to be successfully treated in this way. Memorial Sloan Kettering investigators are also preparing a follow-up study to eventually treat patients with sickle cell disease in a similar fashion.

“Many of the people who have β-thalassemia live in parts of the world that are medically underserved,” Dr. Sadelain explains. “Although the disease is little known in the United States, its incidence and treatment take a large toll worldwide.”

The research that led to this FDA-approved trial was supported by the National Institutes of Health under award numbers HL53750, HL57612, and HL66952; Errant Gene Therapeutics LLC; the Cooley’s Anemia Foundation; the Leonardo Giambrone Foundation; Cooley’s Anemia International; and the Stavros Niarchos Foundation.

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Good morning,
I am hopeful that my nephew and my niece can be saved. As I am writing my nephew is in Algeria. He had several blood tranfusions but now it doesn't seem to work. His hemoglobin level is still low after transfusion. The highest it's been is 8. Now the doctors there are giving him a medecine that is used to treat cancer. My nephew just turned 6 years old (in the hospital). I am hopeful that there is help somewhere. The stem cell therapy seems like the only hope for him and probably his 2 years old sister who right now hasn't had any transfusion yet.
Thank you for all your work, I am sure a lot of parents and family appreciate it

Hoping stem cell can help sickel cell kids real soon.

I am very happy with the news that could potentially save those with B- thalassemia. Although I have Thalassemia Minor and does not need transfusion, I had a stem cell transplant for multiple myeloma. I hope stem cell can also help those with sickle cell and Thalassemia also.

A few questions:

Will the stem cell therapy be applicable to B- thalassemia major patients only? Can it be done on Minors as well?

When the therapy is successful, does that mean that the subsequent generations are free from the disease as well as not carrying the trait?

Do the patients need to preserve the stem cells since birth for the therapy to be conducted on them?

We spoke with Drs. Boulad and Sadelain, and here are their answers: Beta-thalassemia minor is a benign disease that does not require treatment. With the therapy being tested in this clinical trial, doctors are only introducing hematopoietic (blood-forming) stem cells, so all the other cells in the body will remain the same. People will still carry the gene and can pass it on to their children. If this therapy works, the next step may be to try to put the normal beta-globin gene in cord blood stem cells.

Hope treatment will serve the best. Kindly confirm when this treatment will go public, so that all the childrens will have normal life without transfusion. Also confirm that iron level is also important.

Can Cord Blood of non HLA matching normal sibling (2 yrs) be used for stem cell transplant of a Beta-Thalassemia patient (7 yrs)

Thank you for your comment. Our experts indicate that the answer to your question is no; if the cord blood of a sibling is half matched or not matched at all, it cannot be used because of the very high risk of graft rejection and graft-versus-host disease.

Iam from Sudan ,my eldest child was affected with beta thalassemia major since he was 2 years , now 9 years old , he is on regular transfussion , and daily chlating therapy , I am following the gene therpy news since 2007 , specially with our dear mr.Pad Girondi,my quesion is:
when gene therapy expect to be available to the public if every thing go all right???

Thank you for your comment. This therapy is in early clinical trials, so it is too soon to estimate when stem cell therapy could be widely available.

Understood that it is hard to estimate when stem cell therapy can be widely available. However, if you can provide an estimate time of the phase I results in 2013.

According to Dr. Boulad, “Although we will be able to estimate the amount of gene in the reinfused stem cells of at least three patients, the time interval for the expression of the gene is not very well known. This information will potentially be available by the end of the 2013.” Thanks for your comment!

hi !! Iam Ramesh from Hyderabad, INDIA. My daughter, now 5 yrs old is a thal major , We are trying for a second child. Doctors suggested to go for the cord blood banking during the second's child delivery, so that It can be a back up for the newborn itself and if the HLA matches with my first daughter, then a bone marrow transplant is possible in India itself. Please reply. Is it correct.

Hello, my girlfriend and me have been just diagnosed with Beta thalassemia minor. I know that we have 25% of chances that our future child could be affected by Beta thalassemia major and the question is:
- Did you manage to find all the people that fit into the eligibility criteria?
- As stated at, can you confirm that the final results will be provided in July 2014?
- Will this gene therapy be applicable to all types of Beta thalassemia major, independently from the type of chromosome/gene affected?
- If everything goes well (that we all hope and pray for) which can possibly be the next steps in order to start treating patients affected by Beta thalassemia major?
Thank you in advance and sorry for so many questions.

Hi Claudio, we spoke to Dr. Boulad and Dr. Sadelain and they provided answers to your questions. They said the protocol is currently open until July 2014 and patients are still being enrolled. The timing of the results will depend on patient accrual numbers and the levels of gene expression that are seen. They hope these issues will both be solved by July 2014.

If it moves forward, this therapy would be for all types of Beta-thalassemia major independent of the Beta-globin gene mutation.

In order to start treating patients affected by Beta-thalassemia, all (or at least the majority) of patients would need to engraft with the gene and become transfusion independent without any major side effects. The next steps would be production of the vector in larger scale, FDA approval for the vector, and extending the trial to a Phase II study. Licensing the vector to a biotech company may be necessary to broaden access to this therapy, just as it is with any new medication, chemotherapy, or biologic agent.

Thanks for your comment!

My son was diagnosed with CDA when he was 21-months old. He's now 33. When he was diagnosed there were fewer than 200 reported case in the world. He recently learned not only does he have CDA, he also has hemochromotosis to boot. I had resolved myself to the fact that this disease was so rare and so few people were affected that no one wanted to find cure. It was like, "why bother"? It's too late for him now because he has an enlarged heart, liver and super high levels of iron. It didn't help when he lost his job and medical coverage. So thank you for seeing a need to research this disease despite so few people having it. I just wish this had been out there sooner.

Dear Doc Michel,
I am 19 years beta Thalassemia major ,
We meet on the confrence of Delhi in India,you gave me the email of Dr. Farid's ,but I can't contact him,
Can I participate trials of gene therapy?
Please reply me,
Thank you

Gevning sir.I am having a diachorionic diamniotic twin 16 wks pregnancy.we both partners have thal beta trait .we have done CVS for both of babies, out of which one is minor and one is major. Is my major baby eligible for trial .if yes please send me details, I will be very thankful to u .I am very worried about what to do next as we have chosen the option of not to terminate the pregnancy.

Thank you for your comment. Unfortunately, we can’t answer personal medical questions on our blog. However, you can learn more about Memorial Sloan-Kettering’s clinical trial for Beta-thalassemia here: Please note the current trial is only for adults.

I belong to india/new delhi.My daughter aged 20 years is having thal.major.
would like to know how many patients have been taken on clinical trials till date and how they are responsing to treatment.
we look forward to the treatment in future for my daughter.

Nalin, the trial is still in its early stages and it is too soon to say what the outcome will be. Thank you for your comment.

I live in Australia and my 6 year old son has thalassemia major. He has regular blood transfusions and daily chelation therapy. Would he be eligible for the trial? Congratulations on how far you have come to finding a cure. You have given us all hope. Thank you.

how long it will take for the results to come out i.e. when can we expect the treatment ? any time period of the trials. Thousands of patients are waiting for the treatment and eager to know the news.

I am from Andaman & Nicobar Islands in India. My son Mohd. Ashfaq is a Beta Thallassemia major. He was diagonosed at the age of 08 months, and since than he is on regular blood transfusion and on daily chelating therapy. He is now 14 yrs. old. I have been following the Gene Therapy (Thallagen) project since 2006 and I always pray for the success of the project, so that it will cure all the affected childrens in the world. Time will will come that there won't be a single case of Thallassemia in this worlds. My best wishes to Pat. Girondi, Farid Boulad, Michel Sadelain and Isabelle Riviere. I just wanted know when can I expect to treat my son by Gene therapy.

Mohd. Amin Moosa,

The trial is still in its early stages and it is too soon to say what the outcome will be or when gene therapy might be available for treating Beta-Thalassemia. You can see updates from the trial at:

Thank you for your comment.

I would like to get some info and nominate my brother who wants to be a part of this test.
He is Thalasemia- Major patient and 21 years of age.
We are based in Asia and can easily come to US for the research and try this trial.
Kindly let me know where can I get some info about it.

Majid, we are sorry to hear about your brother’s diagnosis. If he would like to make an appointment with one of our specialists, or arrange for a review of his medical record, please ask him to contact our International Center. From outside the United States, he can use AT&T Direct Access. First dial the access number for the country he is in, then 888-675-7722. Or, he may email them at

Thank you for reaching out to us.

My 6yr old son has what they are calling an interleukin 2 signaling defect. Hence everything he gets progressess to something that requires hospital care. He cannot hold titers of hib, tetanus, etc....It took many specialists to figure out what was going on. They really can only offer protective antibx and continual revaccination. This time some CD 56 and NK cell lymphocytosis came back and virtually no tetanus or hib titer at a protective level. Is there anything Sloan might be able to help us with as they monitor blood every 3 months and apparently worse case scenario would be a bone marrow transplant.
thanking you for your time in advance,
Jill Peterson

Dear Jill, we suggest you give our pediatrics department a call at 212-639-5954. They can be reached Mon–Fri, 8:00 am–6:00 pm, ET. They will be able to give you the best sense of the treatment options available to your son. Thanks so much for reaching out.

I noted that the Phase I study completion time has been extended to July 2015 on clinical trials website. There was no formal communication published by mskcc in this respect.

My only suggestion that mskcc can do a better job at communicating the updates on trials.

Good news, dose it use the technology of ES Cell Based Gene Overexpression?

May God bless all the people associated with finding the cure for beta thalassemia and also other diseases.
My son(9 yrs ) was diagnosed with major beta thalassemia at 6 months of age.we live in nyc .He is being treated by Dr.Girdina at NYPH.
He has no sibling match.What is his possible hope with gene therapy

Thank you for reaching out. Memorial Sloan Kettering does have one gene therapy trial for beta thalassemia. You can learn about it here:

You can see a fuller description of the trial here:

For more information about this study and to inquire about eligibility, please contact Dr. Farid Boulad at 212-639-6684 or via e-mail at

I am karteek from India. I am suffering from a genetic disorder called xeroderma pigmentosum. I have consulted many doctors but no one result. They said no cure but I was Hoping this will cure me.

Karteek, at this time MSK is not investigating cell therapy for xeroderma pigmentosum, but there may be other institutions that are. You might want to go to, a database maintained by the US National Institutes of Health that tracks clinical trials around the world. Thank you for your comment.

Dear mskcc Team,
I appreciate your team for the hard work and pray for the success of this study
We will be thankful to you if you can post current update

My daughter is a Thal Maj.patient aged 20years.How far is the genetic cure for thalassemia in reality? And also what may be the cost?Whether it will be available in near future in India?

Umashankar, we are sorry to hear about your daughter. This treatment is still being evaluated in early-phase studies and it’s too early to say when it will be widely available. Thank you for your comment.

Please post latest update of gene therapy in beta thalassemia major
Thank you

Vishal, we sent your question to Dr. Massague, who responded, “We are preparing a new lot of vector for the thalassemia trial and will resume the clinical trial when the vector is available.” Thank you for your comment.

My son is beta thal major. I wanna know the results of the trial of the therapy. I have heard that you r supposed to complete a trial this month. And thanks from my heart that u all r rising hope for us.

Thank you for reaching out. This trial is still ongoing, but if you would like to learn more information, you can contact Dr. Farid Boulad at 212-639-6684 or via e-mail at

Any latest update on gene therapy and where can i get more information as my son which is 12yrs old this year has been doing transfusion since 2 yrs old.. if this could help it would be a miracle for him.

Thank you for reaching out. This trial is still ongoing, but if you would like to learn more information, you can contact Dr. Farid Boulad at 212-639-6684 or via e-mail at

I have had that major since 1962, and when I was 10ish a doctor told me that they will fix this illness as they were already working on gene therapy, I thought he made that up to give me hope, and that is what I have done all my life. Now I am comming to my Middle Ages and still it is not quite ready? I'm beginning to believe I will not live long enough before it is released, but I hope to be wrong and that it's just around the corner. You can reach it but not quite but can't have it! Seems so unfair!