Jewish General Hospital | bacteria against cancer

In the basement of the Jewish General Hospital, a small room formerly dedicated to radiation oncology now houses an imposing machine, nicknamed the PolarTrak. It is here that patients will test an unprecedented therapy for the treatment of cancer from 2023.

Alice Girard-Bosse
The Press

This new research laboratory was inaugurated at the end of June by the Jewish General Hospital and the Quebec firm Starpax Biopharma. The concept ? Bacteria, on the surface of which drugs are attached, are injected directly into the tumor. These small organisms are guided by magnetic fields throughout its volume, in order to destroy it.

The first clinical studies planned on humans will focus on six types of cancer, namely cancers of the pancreas, prostate, head and neck, rectum, vulva and recurrence of breast cancer.

Make way for bacteria

The bacterium called Bn1-S is at the heart of this new technology. This organism, developed in the laboratory thanks to more than 800 mutations, is sensitive to magnetic fields, which makes it possible to control its trajectory with millimeter precision.

The bacteria are injected by endoscopy through the mouth, through the rectum or by injection through the skin: an intervention of about ten minutes. During the injection, the patient is positioned in the PolarTrack so that the tumor is at the point of convergence of the magnetic fields.

The magnetic fields then travel through the tumor, distributing the bacteria throughout its volume. The drug, which is on the back of the bacteria, is gradually released into the tumor. It therefore does not circulate in the blood system. Since toxic agents do not spread throughout the body, side effects caused by traditional treatments are greatly reduced.

Lack of oxygen

The bacteria, which do not need blood vessels to move around, are able to enter the hypoxic areas of the tumor, where the oxygen level is low. This ability is an undeniable advantage in overcoming cancer.

This is because cancerous tumors have lower oxygen levels compared to normal tissues. In this environment, cancer cells proliferate rapidly, consuming almost all the oxygen around them to form a barrier, called the hypoxic zone.

This environment is favorable to them, since it allows them to better resist drugs, standard treatments and attacks from the immune system.

However, Starpax bacteria manage to enter these hypoxic areas naturally, since the oxygen level is the same as that of their culture medium.

After 60 minutes, the bacteria die because the human body temperature is too high for them to survive. But the drugs that were on their surface continue their attempt to destroy the cancer cells.

Beginning of studies

So far, the technology has been tested in preclinical studies in animals, such as monkeys, mice, dogs and pigs. “We had a 100% remission ratio without side effects,” rejoices Mr. Gareau, who is eager to begin clinical studies. “We don’t expect failure,” he says.

The Ministry of Economy and Innovation has granted funding of up to $7 million for the establishment of the PolarTrak room.

“This new room at the Jewish General Hospital will make it possible to innovate thanks to avant-garde treatments, in addition to creating direct spinoffs on the dynamism of research in Quebec,” declared Pierre Fitzgibbon, Minister of the Economy and of Innovation and Minister responsible for Regional Economic Development, at his inauguration.