Scientists have announced a potential major breakthrough in the treatment of an aggressive form of adult Leukemia, but the results are tentative. Here are five things you need to know.
1) What Is The Potential Breakthrough in Leukemia Treatment?
The treatment involves fighting an acute form of leukemia (acute lymphoblastic leukemia or ALL) that is usually lethal in adults. The treatment uses a form of gene therapy that alters the patient’s own immune system so that the immune system attacks the cancer.
Specifically, the T-cells were extracted from the patient and primed to target CD19, a protein present in all ALL cells. The cells were then reintroduced.
The five patients to receive this groundbreaking treatment, aged between 23-66, had all been diagnosed with ALL and, after previously being in remission after intensive chemotherapy, were looking at certain death if they did not receive bone marrow transplants. However, the patients needed to be in remission before they could receive said transplants, something that for many was now an impossibility as they simply were not strong enough to endure another bout of chemo.
This is where the CD19-targeted T cell treatment offered some hope, as it was hoped it could eradicate ALL long enough for patients to achieve remission.
2) Was the CD-19 Targeting Leukemia Treatment Successful?
Five adult patients who had ALL achieved complete and rapid remissions following the CD19-targeting treatment.
Three of the five adults to receive this treatment have been in remission for 5-24 months.
However, two of the adults later died. One died of a blood clot following a bone marrow transplant.
More significantly, the other died of a relapse (though the patient, unlike the others, was unable to have the usual bone marrow transplant).
As implied above, the survivors have all gone on to have bone marrow transplants and remain in remission, though relapse is still possible.
3) What Are The Side Effects of the CD-19 Targeting Treatment?
While manageable, the side effects were potentially life threatening.
Administering primed T-cells created what doctors referred to as a “cytokine storm,” spiking a patient’s fever to 105 degrees. The hormone rush also caused blood pressure to plummet and heart rate to shoot up to dangerous levels. This was managed with close monitoring in intensive care and a steroid treatment.
4) Is This an ALL Cure or Does Further Work Still Need to Be Done?
To be clear, this treatment is in its infancy and studies are ongoing.
Researchers do not know if the treatment will cause any long term side effects (though this is unlikely) and they do not yet know the true longevity of the treatment, that is to say, how long-lasting its eradication of ALL can be.
Studies will now need to be carried out on larger samples of patients to ascertain whether the benefit translates on a wider scale and, in particular, which adults respond best to this kind of treatment (for instance, if the treatment works better among younger adult patients).
It also remains to be seen whether the treatment could mean that subsequent bone marrow transplants were unnecessary. They were offered for ethical reasons, that bone marrow transplants are the regular course of treatment and to deny them to patients who might be facing death would have been wrong. However, as the treatment eradicated all traces of active ALL, it may be that the bone marrow transplant wasn’t needed.
The importance of this very small breakthrough cannot be underestimated, with Carl June, a cancer researcher at the University of Pennsylvania who was not involved in the study, telling the Wall Street Journal a definitive summary on the study’s value: “This has the potential to increase the number of people who would be cured.”
5) Who Carried Out The Study and Where Can I Find More Information?
The study was carried out by Dr. Renier J. Brentjens, specialist in leukemia at Memorial Sloan-Kettering Cancer Center, and a team who hold a patent on the engineered T-cell receptor.
Study sponsors include the National Cancer Institute and Sloan-Kettering.
The findings are reported in the journal Science Translational Medicine.
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