Woman's cancer cured by measles virus overdose

Published May 22, 2014 1:51pm

A year ago, Stacy Erholtz found herself locked in a near-hopeless battle with cancer.

The 49-year-old mother, a resident of Pequot Lakes, Minnesota, USA, suffered from myeloma—a blood cancer that strikes the bone marrow with malignant blood plasma cells. With few options at hand and the clock steadily ticking, she signed up for an experimental virotherapy trial with doctors at the Mayo Clinic.

According to the clinic:

"Oncolytic virotherapy – using re-engineered viruses to fight cancer – has a history dating back to the 1950s. Thousands of cancer patients have been treated with oncolytic viruses from many different virus families (herpesviruses, poxviruses, common cold viruses, etc.). However, this study provides the first well-documented case of a patient with disseminated cancer having a complete remission at all disease sites after virus administration."

The doctors injected Erholtz with 100 billion units of an engineered measles virus (MV-NIS), enough for about 10 million doses of vaccine. At that point, she felt as if she had nothing to lose.

"My mindset was I didn't have any other options available, so why wouldn't I do it? I had to have failed all conventional treatment to do that trial. That actually happened last March," said Erholtz. She had tumors scattered all over her body, with one even growing large enough to damage her skull.

Thankfully, her gambit paid off: as the journal Mayo Clinic Proceedings reports, Stacy Erholtz has been completely cleared of cancer for six months.

Groundbreaking treatment

The cancer was not easy to endure, and her last, desperate bid to fight was no walk in the park, either. Erholtz suffered from a painful headache, shaking, vomiting, and a high fever immediately after her hour-long treatment.

However, Erholtz reported an improvement in her condition thirty-six hours after her treatment. Her tumors had begun to shrink, and completely disappeared as the weeks passed.

“This is the first study to establish the feasibility of systemic oncolytic virotherapy for disseminated cancer,” said Dr Stephen Russell, the paper's first author and co-developer of the therapy. “These patients were not responsive to other therapies and had experienced several recurrences of their disease.”

Dr Russell calls the procedure “a huge milestone.”

Since the 1950s, re-engineered viruses have been used in the fight against cancer through oncolytic virotherapy; however, this is the first instance where the patient experienced a complete and total remission of cancer in all disease sites after the treatment.

"We have known for some time viruses act like a vaccine,” explained Dr Russell. “If you inject a virus into a tumor you can provoke the immune system to destroy that cancer and other cancers. This is different, it puts the virus into bloodstream, it infects and destroys the cancer, debulks it, and then the immune system can come and mop up the residue."

Additionally, while the engineered virus had previously been tested in mice, the treatment marked the first time they tried it on human subjects.

“What this all tells us is something we never knew before – we never knew you could do this in people,” Dr Russell said. “It’s a very important landmark because now we know it can happen. It’s a game changer.”

“AndI think it will drive a development in the field.”

The catch

The treatment does have one apparent weakness, though: patients with immunity to the measles virus would most likely be immune to the engineered virus as well. This is why such a large dose was required for Erholtz; the doctors needed to be certain that the virus could get past her immune system to kill her cancer cells.

In addition, Erholtz had limited previous exposure to the virus, and her immune system was weakened to the point where it could not successfully fight it off.

One other patient who joined Erholtz during the first trial did not experience the same level of success, as her cancer resurfaced after nine months. Dr Russell believes that the treatment may not have worked as well on the other patient because her myeloma specifically targeted her leg muscles.

Still, Dr Russell and the rest of the team are preparing for “phase 2,” manufacturing more of the specially-engineered measles virus for further trials. "It's like a call to action. It's not just good for our virus. It's good for every virus everybody's developing as a cancer therapy. We know this can happen," said Dr Russell.

As for Erholtz – who is scheduled for an annual checkup in a month's time – her recovery has definitely put her in a cheerful and optimistic disposition.

“I think it's just remarkable. Who would have thought?” — TJD, GMA News

Tags: cancer, cancercure, medicine, virus, measles