One of the deadliest viruses could be the cure in fighting brain tumors. Researchers have tested a genetically modified poliovirus on a small study and found the outcome to be better than expected.
An Enemy Becomes An Ally
The modified poliovirus that was given to the test subjects helped their bodies attack cancer, the doctors stated. The test was the first human trial. The doctors noted that the poliovirus didn't help the majority of the patients and it did not improve median survival. The participants who claimed to have a long-lasting benefit, about 21 percent, were still alive 3 years later, compared to the 4 percent in another group of brain tumor patients.
Glioblastoma is the most common malignant brain tumor. The researchers from Duke University decided to use the modified poliovirus due to the virus' ability to infect the nervous system. In the study, the researchers removed one of the virus' genes to prevent it from causing a person to have polio and replaced it with a harmless virus — Rhinovirus.
Rhinovirus causes a common cold to occur. The modified virus was then infused directly into the patient's brain where the tumor was. The researchers did this by using a tube that was inserted into a hole in the brain.
The researchers stated that the engineered virus is able to infect and kill brain tumors cells, as well as trigger the patient's immune system so that it can attack the tumors. The test was conducted between 2012 and 2017 on 61 patients whose tumors had recurred after prior treatments.
The overall median length of survival was 12.5 months for the patients who were treated with the virus. This was compared to 11.3-month survival rate for a group of similar patients that were treated in the past.
Two years after the treatment, the researchers noted that two group's survival rate began to get better. The researchers noted that two patients survived for more than six years, and one patient has survived for more than five years.
"We're extraordinarily encouraged by what we see with this data. It's phenomenal," Mitchel Berger, who is the chairman of neurosurgery at the University of California, San Francisco and director of its center for brain tumors, stated.
The results were published in the New England Journal of Medicine and will be presented at a conference in Norway on Tuesday, June 26.