New Hope In Immunotherapy

"By using two types of viruses, or multiple types of biological agents, you're really attacking the cancer in multiple ways at the same time. It doesn't give cancer cells a chance to escape. And so the chances of success are much higher."
"We found that when normal cells become cancerous, it's like they are making a deal with the devil. They acquire genetic mutations that allow them to grow very quickly, but these same mutations also make them more susceptible to viruses."
Dr. John Bell, senior scientist, The Ottawa Hospital

"We all know that cancer hides. It hides amongst our normal, healthy cells. It hides from our immune response."
"[New study findings hold] profound implications [for the treatment of cancer]. The potential is staggering."
Dr. David Stojdl, senior scientist, Children's Hospital of Eastern Ontario, Ottawa

"The idea behind this trial is to use the Adenovirus to prime the patient's immune system to recognize their cancer, and then use the Maraba virus to directly kill their cancer and further stimulate their immune system to prevent the cancer coming back."
"I'm very excited about this trial because I think it represents in many ways the future of cancer therapy."
Dr. Brian Lichty, associate professor, McMaster University, Hamilton

The three medical specialists, Drs. Bell, Stodjdl and Lichty once worked together fifteen years ago when they were all three at The Ottawa Hospital.  At that time they began their investigation into cancer-fighting viruses. Now, a clinical trial has been launched into the effectiveness of fighting advanced tumours of cancer patients with viruses. The trial is being led by The Ottawa Hospital and is featured as the first such trial in the world, deploying two viruses simultaneously as a biological assault on cancer cells.

The Maraba virus in modified form is to be used in combination with the Adenovirus which is derived from the common cold virus, while the Maraba virus has been isolated from Brazilian sandflies. For over a century scientists have attempted to harness the power of viruses which are highly-evolved infectious agents of ancient lineage, capable of abducting and destroying body cells.

Cancer cells are capable of wild replication, yet are oddly susceptible to infection. In recent years scientists have come to an understanding of how it is that viruses work on a molecular level. That understanding has enabled them to engineer viruses to make them safe for testing on humans. Those viruses are known to seek out and destroy hard-to-find cancer cells.

The Maraba virus has been genetically modified in laboratories in Ottawa with the capacity to sense the difference between tumour cells and normal cells, then proceed to attack the cancer cells with the aid of the body's own immune system. The clinical trial will run its course by November of 2017 with some 79 patients agreeing to take part. These are patients whose tumours have resisted conventional treatment. Some patients will be inoculated with one of the viruses while most are scheduled to receive both in two-week-apart dosages.

When the trial concludes, another year will be required to enable researchers to analyze all the extracted data and finally publish their findings. And if the trial manages to duplicate results realized by researchers using animal models, the field will be opened for new, more successfully advanced treatments for cancer patients. The clinical trial requires participation by patients with solid tumours particularly patients whose cancer cells express a specific protein, MAGE-A3, which leaves them vulnerable to the engineered viruses.

The clinical trial is funded by the Ontario Institute for Cancer research, with hospitals in Ottawa Toronto, Hamilton and Vancouver taking part. This race to develop genetically modified viruses is not confined or particularly unique to Canada. Scientists around the globe are involved in developing genetically modified viruses and other biological agents to target and kill cancer cells, in combination with actively engaging the body's own immune system.

This research field is called biotherapy, or immunotherapy, holding out promise of powerful new treatments more readily tolerated than conventional chemotherapy.

"I received excellent care from many doctors [dealing with her anal cancer diagnosed in 2012], nurses and support staff at The Ottawa Hospital, but despite this, I was told in 2013 that my cancer had spread to both of my lungs."
"In total, I had more than 30 rounds of chemotherapy and six weeks of radiation and while there may have been some temporary effect on my cancer, the cancer kept spreading."
"The cancer was, of course, very bad, but in some ways, the chemotherapy was even worse. I experienced severe nausea, I couldn't eat, I lost all my hair. I developed sores in my mouth, and my hands and feet went numb."
"Eventually, I knew I couldn't go on that way. So when Dr. Derek Jonker [principal investigator for the clinical trial] asked me if I wanted to try a new viral therapy for cancer, I was very intrigued. I was of course a bit nervous because he said this virus had never been tried in humans before, but I felt like this might be my last hope."
"...For the next couple of days [after viral infusion directly into the bloodstream], I felt like I had the flu, but it was nothing like chemotherapy. The symptoms of the virus were easily managed and short-lived. I received a second treatment of virus on June 5, and this time, I only had some mild nausea."
"It is too soon to say if this therapy has affected my cancer, but I am very glad that I had the opportunity to participate in this trial because I know that it may contribute to better therapies that could help other people."
Christina Monker, 75, former nurse, participant in virus clinical trial

Christina Monker, 75, who is one of the first patients to take part in a clinical trial that uses a combination of viruses to treat cancer, is photographed at the Ottawa Hospital Friday July 10, 2015.