An American researcher has come up with a cowpox-style virus that, in the laboratory, can kill every type of cancer and has shrunk tumors in mice. The treatment is called CF33 and is being developed in Australia by biotech company Imugene to treat the millions of humans afflicted with carcinomas.
Cowpox succeeded in preventing smallpox 200 years ago and is harmless in humans. Clinical trials have shown that combining cowpox with other viruses can kill cancer. The new treatment would inject the engineered virus directly into targeted tumors where the infectious viral cells multiply and force the unhealthy cells to burst open or rupture.
CF33 uses naturally occurring or genetically modified (GM) oncolytic viruses to infect and kill tumor cells. For more than 100 years, physicians have known that some viruses cause cancer cells to rupture and die without harming healthy cells – plus, they trigger a broader immune system response within the body.
The first oncolytic virus therapy was approved by the U.S. Food and Drug Administration (FDA) in October 2015. Talimogene laherparepvec (T-VEC) is used to treat metastatic melanoma that can’t be removed surgically.
Now, U.S. cancer expert Professor Yuman Fong is based at the City of Hope Comprehensive Cancer Center in Los Angeles, California but is in Australia now to organize clinical trials there and in other countries. His goal is to facilitate bringing his breakthrough therapy to the commercial market.
After targeted cancer cells explode from the viral treatment, the immune system goes the alert to seek and destroy other cancerous cells inside the body.
Prof. Fong explained why using viruses to cure cancer remained elusive and vexed researchers for so long:
“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. The problem was if you made the virus toxic enough to kill cancer you were worried it would also kill man.”
The American Cancer Society gives these facts about the potentially terminal illness which has been uncurable up to now and cost Americans an estimated $147.3 billion in 2017 to treat:
- In 2018, an estimated 1,735,350 new cases of cancer will be diagnosed in the United States and 609,640 people will die from the disease.
- The most common cancers (listed in descending order according to estimated new cases in 2018) are breast cancer, lung and bronchus cancer, prostate cancer, colon and rectum cancer, melanoma of the skin, bladder cancer, non-Hodgkin lymphoma, kidney and renal pelvis cancer, endometrial cancer, leukemia, pancreatic cancer, thyroid cancer, and liver cancer.
- Cancer mortality is higher among men than women (196.8 per 100,000 men and 139.6 per 100,000 women).
- Approximately 38.4% of men and women will be diagnosed with cancer at some point during their lifetimes (based on 2013–2015 data).
- In 2017, an estimated 15,270 children and adolescents ages 0 to 19 were diagnosed with cancer and 1,790 died of the disease.
Prof. Fong has targeted next year to test his new cancer cure on human patients diagnosed with triple-negative breast cancer, melanoma, lung cancer, bladder, gastric, and bowel cancers.
Successful drug testing on lab rodents is no guarantee that the treatment will work on people but Fong remains optimistic that this will be the case.
U.S. scientists were already using the virus, which causes the common cold, to treat brain cancer. In some patients, the cancer vanished for years before it returned; in others, tumors shrank significantly.
Similar therapeutic value was noticed by a form of the cold sore virus called Imlygic or T-Vec which was found to help the body’s immune system recognize and destroy tumors and melanoma cells in the body.
The virus used by Fong is called vaccinia, a genetically stable double-stranded DNA virus in the Poxviridae family. The active component of the vaccine that eradicated the serious infectious disease smallpox has treated millions of humans safely since viral oncolysis was demonstrated in a laboratory in 1922.
Fong’s cancer cure combines genomic sequences from multiple vaccinia strains to create a new safe, yet powerful, virus:
“CF33 has two genes, Human Sodium-Iodide Symporter (hNIS) to enable imaging to track the virus in vivo and mediate targeted radiotherapy, as well as anti PD-L1 to enable enhancement of anti-cancer immunotherapy.”
Advantages of treatments using oncolytic viruses include:
- Targets tumors
- Self amplifies
- Effective for primary, metastatic, and recurrent tumors
- Minimal side effects
- Stimulates immune system to recognize tumor
Cancer immunotherapy company Imugene has contracted to pay City of Hope license fees comprising an upfront payment, annual maintenance fees, development and commercial milestone payments, a royalty on net sales and sublicensing fees. Imugene has entered an agreement to acquire 100 percent of the unlisted company Vaxinia for an upfront cash payment of A$462,500 and the issue of Imugene shares valued at A$1.6m.
The CF33 licensing deal is subject to shareholder approval. The novel cancer cure will need to demonstrate superior effectiveness in clinical studies to attract a pharmaceutical partner.