Immunotherapy strongly improves prognosis of babies with leukemia

PRESS RELEASE: PRINCESS MÁXIMA CENTER FOR PEDIATRIC ONCOLOGY

EMBARGO: WEDNESDAY, APRIL 26, 2023 AT 17:00 ET

Immunotherapy treatment is safe and effective for babies with leukemia, according to new clinical trial results published in the New England Journal of Medicine. Immunotherapy with blinatumomab leads to a strongly improved survival rate – from 66% to 93% – for children with an aggressive form of acute lymphoblastic leukemia (ALL). They also had fewer side effects from the treatment. Based on the results, blinatumomab will now become standard treatment worldwide for babies with this aggressive form of leukemia.

Three quarters of babies with acute lymphoblastic leukemia (ALL) – three babies a year in the Netherlands – have a particular fault in the DNA of their leukemia cells. This so-called KMT2A rearrangement leads to an aggressive form of ALL with a poor prognosis. Despite intensifying chemotherapy, the prognosis for these babies has not improved in recent decades.

Intensive chemotherapy works very well for half of the babies. But in the other half of the children, the disease returned within two years, or children died from the disease or sometimes from the side effects of the therapy. 90% of recurrences – when the cancer comes back – occur during the two-year course of therapy.

Immunotherapy with the drug blinatumomab is already offered to some adults and older children with ALL. It was still unclear whether this treatment is also well tolerated and effective in babies. Blinatumomab binds to leukemia cells on one side and to immune cells on the other side. This connects the immune cells to the leukemia cells and clears them up.

International clinical trial

Researchers at the Princess Máxima Center for pediatric oncology in the Netherlands led an international clinical trial looking at the safety and effectiveness of blinatumomab in babies with ALL. Between 2018 and 2021, 30 children in 9 countries were treated with blinatumomab. This was added to the existing chemotherapy treatment, the so-called Interfant-06 protocol. The team compared the outcomes with those of 214 children who had been treated in previous years with the Interfant-06 standard therapy: the same treatment, without blinatumomab.

Significant improvement

The survival rate of babies who received one month of immunotherapy in addition to chemotherapy was significantly higher: 93% of them were still alive two years after diagnosis, compared with 66% of children who had only been treated with chemotherapy in the past. This brings the survival of the babies with a KMT2A rearrangement in their leukemia cells to the level of the average survival of older children with this form of blood cancer.

Two years after diagnosis, 18% of babies treated with blinatumomab saw their cancer come back, or died from their disease. This also indicates a strong improvement compared with babies treated within the Interfant-06 protocol, without immunotherapy. In that group, 51% had a recurrence or death during the two-year treatment with chemotherapy.

The results of the international clinical trial were published today (Wednesday) in the prestigious New England Journal of Medicine. The study was funded by the Princess Máxima Center Foundation and the pharmaceutical company Amgen.

Dr. Inge van der Sluis, pediatric oncologist and clinical pharmacologist at the Princess Máxima Center for pediatric oncology, led the clinical study. She says:

‘It’s fantastic to see that we have made such progress for babies with ALL: the addition of immunotherapy to chemotherapy leads to much better survival and fewer side effects. We were already familiar with this immunotherapy from studies in other patient groups. This is the first time that we tested blinatumomab as a first-line treatment, and for the first time in such young children.

‘This was a small study, but with a clear enough result that all babies with this form of leukemia are now receiving immunotherapy as part of standard treatment. We want to confirm the effect of blinatumomab in a larger study with more children. We also want to see whether babies benefit from two courses of blinatumomab and a reduction in chemotherapy, in order to improve their quality of life even further.’

Prof. dr. Rob Pieters, medical director and pediatric oncologist at the Princess Máxima Center for pediatric oncology, leads the research group that carried out the study. He says:

‘The survival of children with acute lymphoblastic leukemia has risen to more than 90% in recent decades, but the cure rate for babies has lagged behind. These young children are much more likely to have an aggressive form of the disease. That's why in 1999 we founded a large international collaboration of more than 25 countries, looking for improvements in treatment.

‘Babies with leukemia often have a recurrence early in treatment. That’s why it was important to give the immunotherapy right at the start of the treatment. It’s wonderful to see that this is yielding such a good result, and that we are implementing the addition of immunotherapy into worldwide standard treatment straight away.’

- ENDS -

Notes to editor

For more information about this message and/or about the Princess Máxima Center for pediatric oncology, please contact one of our press officers via email: pers@prinsesmaximacentrum.nl.

Juul Zwinkels, communication advisor research: +31 (0)6-50 17 31 83.

Maud Burgers, sr. corporate communication & marketing advisor: +31 (0)6-22 94 88 04.

About acute lymphoblastic leukemia and blinatumomab in babies

On average, acute lymphoblastic leukemia is diagnosed in four babies per year in the Netherlands. Three of them, so 75%, have the aggressive KMT2A variant. This form occurs in only 2% of older children with ALL.

Blinatumomab has been included in the current international treatment protocol for infants with KMT2A leukemia, Interfant-21, based on early results from this study. This protocol has been used in the Netherlands since December 2021 and will soon be implemented in 27 countries worldwide.

About the Princess Máxima Center for pediatric oncology

When a child is seriously ill from cancer, only one thing matters: a cure.

Every year, 600 children in the Netherlands are diagnosed with cancer. Sadly, one in four of these children dies. That is why in the Princess Máxima Center for pediatric oncology, we work together with passion and without limits every day to improve the survival rate and quality of life of children with cancer. Now, and in the long term. Because children have their whole lives ahead of them.

The Princess Máxima Center is no ordinary hospital, but a research hospital. All children with cancer in the Netherlands are treated here, and it’s where all research into childhood cancer in the country takes place. This makes the Princess Máxima Center the largest pediatric cancer center in Europe. More than 900 healthcare professionals and 450 scientists work closely with Dutch and international hospitals to find better treatments and new perspectives for a cure.

In this way, we offer children today the best possible care, and we take important steps to improve survival for children who cannot not yet be cured.