A Minnesota woman’s blood cancer has gone into complete remission after she was given a high dose of the measles vaccine during a clinical trial. This breakthrough trial proves the “proof of concept” theory, validating that a single massive dose of intravenous viral therapy can kill cancer.

Stacy Erholtz was out of traditional treatment options when she chose to take part of an experimental treatment at the Mayo Clinic. When Erhotlz was injected with enough measles vaccine to inoculate 10 million people, something incredible happened. Her blood cancer went into complete remission, changing from life-threatening to “undetectable” before her doctors’ eyes.

“It’s a landmark. We’ve known for a long time that we can give a virus intravenously and destroy metastic cancer in mice. Nobody’s shown that you can do that in people before,” said Dr. Stephen Russell, lead researcher of the project, the Star Tribune Health reported. “Without trying to hype it too much, it is a very significant discovery,” Dr. John C. Bell for the Centre for Innovative Cancer Research in Ottawa added to the online publication.

How It Works

Scientists know that viruses can kill cancer, at least in animals. The Star Tribune explains how a virus can bind to tumors and uses them as hosts to replicate their own genetic material. This will cause the cancer cells to eventually explode and release the virus. Safe antivirals have been developed to do just this. They are able to carry radioactive molecules to help destroy cancer cells without causing damage to healthy cells that surround the tumors. The immune system will then get rid of any remaining cancer that carries the vaccine’s genetic imprint. There are two approaches to vaccine cancer treatment: Inject the virus directly into tumors to get past their defenses or inject it into the bloodstream and hope it will seek out tumors and overwhelm them. The latter was the method researchers used in Erholtz’s trial.

Certain viruses can be used to target particular areas of the body. For example, pneumonia and influenza damage the lungs, while hepatitis affects the liver. “We have a virus that can do that selectively to a tumor without at the same time causing damage to normal tissues in the body,” Russell added to the Star Tribune.

Why It Works Now

What sets Erholtz success story from the many failed clinical trials is unprecedented large amount of the measles vaccine that she was injected with. The normal dose of vaccine contains 10,000 infectious units of the virus. In this trial, patients were given one million infectious units and these were gradually increased until the volunteers were eventually injected with 100 billion infectious units. Unfortunately, the second volunteer in the study did not have as much success as Erholtz. Researchers believe that this failure may have been largely due to the dosage amount. “I think if we had been able to give bigger dose, we might have got a better outcome in that second patient,” Russell explained. Unfortunately the procedure cannot be repeated on the same patient twice because once the vaccine has been delivered, the immune system will recognize it and attack it before it has time to reach the tumors.

Future Looks Bright

It is likely that this method will one day become the standard for treatment of cancers such as myeloma or pancreatic cancer within the next three to four years, Dr. Tanios Bekaii-Saab, a researcher at the James Cancer Hospital and Solove Research Institute in Ohio predicted to the Star Tribune. Still, at the moment, although Erhotlz successful trial is exciting, the study must be confirmed in large randomized clinical trials before it becomes a standardized treatment option. Unless we get to the third stage of development, we are only cautiously optimistic,” Saab explained.

Trials that use vaccines to treat cancer are going on throughout the United States, such as the NeuVax clinical trial that plans to use similar methods to create preventive strategies for patients at risk for breast cancer recurrence. Another similar study run by the Providence Cancer Center will use dangerous bacteria instead of viruses to treat glioblastoma, a common type of brain cancer.