Poliovirus, the virus responsible for the deaths of hundreds of people and the crippling of Franklin D. Roosevelt, is being used to treat glioblastoma, the most common and one of the worst types of brain cancer.
After two decades of creating, studying, modifying, testing a version of the poliovirus, Dr. Matthias Gromeier finally reached his goal of using it to combat cancer. The investigational therapy, known as PVSRIPO, was put to use.
How it works: The modified version of the poliovirus is laced with rhinovirus (the virus that causes the common cold). This allows the poliovirus to enter healthy brain cells but not replicate, so it can’t hurt the cells. However, when the poliovirus enters the cancer cell, it is able to replicate (because cancer cells have a different biochemical makeup than regular cells) and kill the cancer cell like regular polio does to regular cells. Like this, the poliovirus targets and kills cancer cells while leaving regular, healthy cells unharmed.
“Eligible patients need to have small focally recurrent glioblastomas that have undergone current standard of care,” said Dr. Ricardo Komotar, director of surgical neurooncology at University of Miami School of Medicine.
Stephanie Lipscomb fit just that description.
Lipscomb was the first patient to enter the clinical trial. She was 20 years old when doctors discovered a glioblastoma – a brain tumor – the size of a tennis ball. She was told she would live five more years, at best.
Lipscomb and her family decided to have surgery to remove it, although they knew of the high resurgence rate for this type of cancer.
Two years later, the tumor reappeared. Lipscomb’s neuro-oncologist, Dr. Annick Desjardins proposed she join a clinical trial using the poliovirus to enter cancerous cells and kill them. The placement of Lipscomb’s tumor in the right frontal lobe made her an ideal candidate for the treatment; doctors wouldn’t have offered to tamper with other areas of the brain dealing with language and visual skills.
It took months for the virus to begin killing the cancerous cells, but in July 2013, Lipscomb received a brain scan and discovered her tumor was the size of a pea. Although the tumor shrunk, Desjardins reminded Lipscomb that there was a possibility of it growing again. Regardless of what the doctors said Lipscomb remained hopeful the tumor would not grow again.
As of now, 50% of participants in the trial have succumbed to their diseases, but in two patients suffering form glioblastoma, doctors cannot detect cancer three years after administering the poliovirus.
“I definitely see this number [amount of successful patients] improving as the clinical trial progresses and the technology improves,” said
Dr. Gromeier has been using the same poliovirus to “unlock” other types of cancer cells in the lab. These include melanoma, prostate, colorectal, and pancreas cancer. Animal and human trials are yet to be done but this continues to be a breakthrough in the world of medicine and the treatment of cancer.
Dr. Komotar of UM’s School or Medicine agrees “over time this technique will improve not only for brain cancer but also for other malignancies.”