For decades, a deadly type of childhood cancer has eluded the best tools of science. Now doctors have come up with an unusual treatment: releasing millions of copies of a virus directly into children’s brains to infect their tumors and stimulate an attack by the immune system.
A dozen children treated in this way lived more than twice as long as similar patients in the past, doctors said Saturday at a conference of the American Association for Cancer Research and the New England Journal of Medicine. .
Although most of them died due to their illness, there are a few who live in good condition several years after treatment, which is virtually unheard of in this situation.
“This is the first step, a critical step,” said the study’s leader, Dr. Gregory Friedman, a child cancer specialist at the University of Alabama at Birmingham.
“Our goal is to improve it,” probably by testing it when patients are first diagnosed or combining it with other therapies to boost the immune system, he said. Patients in the study were given an experimental approach after failing in other treatments.
The study included gliomas, which account for 8% to 10% of childhood brain tumors. They are usually treated with surgery, chemotherapy, or radiation therapy, but are often repeated. Once they do, the average survival is less than six months.
In these cases, the immune system has lost the ability to recognize and attack cancer, so scientists have been looking for ways to make the tumor a new target. They were targeted at the herpes virus, which causes cold sores and causes a strong immune system response. A suburban Philadelphia company called Treovir developed a treatment that genetically modified the virus to infect only cancer cells.
Using small tubes inserted into the tumors, doctors administered the altered virus to 12 patients aged 7 to 18 whose cancer had worsened after the usual treatments. Half also received a dose of radiation, which is believed to help spread the virus.
Eleven demonstrated in imaging tests or tissue samples that the treatment worked. The average survival was just over a year, more than double what had been seen in the past. Last June, the limit for analyzing these results, four were still alive at least 18 months after treatment.
The tests also showed high levels of specialized immune system cells in their tumors, suggesting that the treatment had recruited the body’s necessary help to attack the disease.
No serious safety issues were seen, although there were several complications related to the procedure and mild side effects, including nausea, vomiting, diarrhea, and fatigue.
Jake Kestler received treatment when he was 12 years old.
“It simply came to our notice then. He lived a year and four months later, “long enough to celebrate his mitzvah bar, go with his family to Hawaii and see a brother born,” said his father, Josh Kestler, a financial services executive in Livingston, New York. Jersey.
Jake died on April 11, 2019, but “we don’t regret” trying the treatment, said Kestler, who with his wife has created a foundation, Trail Blazers for Kids, to continue research.
“It’s a devastating disease for these patients and their families,” and early results suggest that virus treatment is helping, but it needs to be verified in a larger study, which doctors are planning, Dr. Antoni said. Ribas, a cancer specialist at the University of California, Los Angeles, and chair of the conference group.
Friedman said studies are also continuing in adults and that there are plans for other types of childhood brain tumors. U.S. government grants and several foundations paid for the study and several doctors have financial ties to Treovir.
Currently, only a similar antivirus therapy is approved in the United States: Imlygic, also a modified herpes virus, to treat melanoma, the most serious type of skin cancer.
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The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.