The Brazilian sandfly carries the Maraba virus. The Adenovirus is derived from the common cold. Three Canadian researchers have discovered that these viruses can be modified and combined to attack and kill cancer cells and stimulate an anti-cancer immune response. 

Based on the promising results of tests on mice, the researchers believe a therapy using the two viruses could fight cancer and have fewer side effects than conventional chemotherapy and radiation.

They have launched the world’s first clinical trial of the treatment. Funded by the Ontario Institute for Cancer Research, the trial will ultimately include around 75 patients at hospitals in Ottawa, Toronto, Hamilton, and Vancouver. All the patients have cancerous tumours that have not responded to conventional treatment. 

New hope for lung cancer

One of the first patients in the trial is Christina Monker. The 75 year-old was diagnosed with cancer in 2012, and the disease spread to both of her lungs despite six weeks of radiation therapy and multiple rounds of chemotherapy. She enrolled in the trial and started treatment in June.

Undoubtedly, there will be other patients in the trial with a similar experience. Lung cancer is the most commonly diagnosed cancer in Canada and is the leading cause of death for both men and women. In fact, deaths as a result of lung cancer will represent 27 percent of all cancer fatalities this year.

“The emergence of this biotherapy is offering real promise of curbing the disturbing growth rate for lung cancer”

The Ontario Lung Association is raising funds to support a follow-up trial that will begin in 2016 and focus specifically on lung cancer patients. The goal is to increase the number of lung cancer patients able to receive this novel therapy. 

“Without a doubt, the emergence of this biotherapy is offering real promise of curbing the disturbing growth rate [of lung cancer],” says Peter Glazier, Vice-President of Development at the Ontario Lung Association. “It offers those affected by this deadly disease the one thing that has been missing for far too long — hope.” 

Glazier adds that the trial could “truly revolutionize” the way lung cancer is treated.  After the first trial ends in November 2017, researchers will analyze the data and publish their findings. That could take up to a year.  The three doctors involved in this research — David Stojdl , John Bell, and Brian Lichty —  started investigating cancer-fighting viruses when they worked together at Ottawa Hospital 15 years ago.

Immunology holds great promise

For decades, scientists tried to harness the power of a virus, which infects and destroys cells, to attack cancer cells. But, it wasn’t possible until recently, when scientists came to understand how viruses work on a molecular level.

Researchers are now modifying viruses to kill cancer cells, and they are finding ways to trigger the body’s immune system to fight cancer.

The clinical trial uses both tactics

“The idea behind this trial is to use the Adenovirus to prime the patients’ immune systems to recognize their cancer. Then use the Maraba virus to directly kill their cancer and further stimulate their immune system to prevent the cancer from coming back,” says Dr. Lichty, now an Associate Professor at McMaster University. “We’re enthusiastic about the potential of this unique therapy.”

Immunotherapy, the prevention or treatment of disease with substances that stimulate the body’s immune response, is the most dynamic area of research in oncology. “There will likely be dramatic developments in this field in the next five years,” says Dr. Lichty.

The possibility of seeing new and powerful treatments that are easier to tolerate than chemotherapy offers hope to the millions of people affected by cancer.