An Australian immuno-oncology company, Imugene Ltd, announced that it is about to enter the clinical stages of developing a cowpox-based oncolytic virus technology that could be used to treat and help kill virtually any type of cancer in the human body.
There could be hope for millions of people around the world and a ground-breaking revolution in cancer research. Using a virus to treat a disease might sound like something out of a zombie-apocalypse movie, but it’s been done before and history is about to repeat itself.
In 1796, English physician Edward Jenner discovered that milkmaids who had been exposed to cowpox never got sick with smallpox. He took a fluid sample from a cowpox blister to inoculate a child at a time when smallpox was a plague in Europe. The child was then inoculated with a smallpox sample and he never got sick with the disease. The cowpox matter produced antibodies that destroyed the smallpox virus and made the immune system resistant to the deadly strains.
Cowpox in humans is a self-limited disease with an extremely low mortality rate, and there have only ever been two reported deaths associated with cowpox. Smallpox, on the other hand, was deadly, highly contagious and could wipe out half a town within weeks. The smallpox vaccine was the first successful vaccine to be developed, based on cowpox.
Penetrate – Replicate – Explode
The oncolytic (cancer-killing) virus was developed by a world-renowned oncologist and scientific founder of Imugene, professor Yuman Fong at the City of Hope Comprehensive Cancer Center in Los Angeles, California. Oncolytic viruses are a group of naturally-occurring, self-replicating viruses that can penetrate a cancer cell and cause it to explode. This technology is astounding and highly impressive.
Fong and his team developed a genetically modified oncolytic virus, CF33 based on cowpox. Imugene has acquired Vaxinia Pty Ltd and a globally exclusive license to develop CF33. CF33 is a chimeric vaccinia developed by the combination of several strains of the cowpox virus to produce a safer and more effective virus. CF33 strains have a short life-cycle and they multiply quickly from cell to cell. However, the scientists explain that the vaccinia strains do not penetrate the host’s genome or cause a genetic mutation
Trials have shown that CF33 can destroy almost any cancer type in a petri dish (in vitro). There have been promising results in mice as well, demonstrating tumor suppression without harming the host. As for human trials, which are set to begin soon, they are targeting patients suffering from melanoma, invasive ductal carcinoma (IDC), lung cancer, triple-negative breast cancer, bowel cancer, gastric cancer, and several other types. The treatment is said to work in two ways: targeted destruction of cancer cells and activation of the immune system to improve chances of survival.
“There was evidence that viruses could kill cancer from the early 1900s when people vaccinated against rabies had their cancer disappear, they went into remission,” said Fong to The News. “The problem was if you made the virus toxic enough to kill cancer you were worried it would also kill man.”
However, Fong is positive that the treatment would not be fatal or harmful to human beings and the future looks promising for successful clinical trials.
Clinicals are set to begin in 2020
The first phase of clinical trials has been scheduled to commence next year in the United States. 30 volunteering cancer patients with advanced solid tumors will pioneer the human phase of the treatment. The research team working on the virus is fairly certain of clinical success, but until the trials are completed and internationally vetted, no one can say for sure. The treatment is still a long way from being commercially available – but there’s hope.
According to Professor Sanchia Aranda, chief of Cancer Council Australia, cancer cells have a high tendency to mutate and evolve rapidly upon attack.
“When it is tested in a human we will see whether the immune system mounts a defense against the virus and knocks it off before it gets to the cancer or there could be nasty side effects,” she said. “Cancer cells are very clever, they are true Darwinians that mutate to survive and there is a likelihood they will evolve to become resistant to the virus as they do now to become resistant to chemotherapy and immunotherapy.”
Cancer has been treated for decades with chemotherapy, surgery, radiotherapy, cryoablation, and hormone therapy. These methods are usually straining on the patient and result in a low quality of life through the course of treatment. The CF33 virus technology, a form of immunotherapy, promises a less devastating treatment course for cancer patients and would hopefully improve clinical response and survival rates.