Stacy Erholtz, a 50-year-old mom from Pequot Lakes, MN had battled myeloma, a blood cancer that affects bone marrow and had few options left.
Although she had been through chemotherapy treatments and two stem cell transplants, it wasn’t enough. Scans soon showed she had tumors growing all over her body – one on her forehead, destroying a bone in her skull and pushing on her brain that her children named Evan. Cancer had also infiltrated her bone marrow.
As a result, doctors at the Mayo Clinic injected Erholtz with 100 billion units of the measles virus – enough to inoculate 10 million people – as part of a two-patient, proof of principle clinical trial. Her doctor said they were entering the unknown.
Five minutes into the hour-long process, Erholtz got a horrible headache. Two hours later, she began shaking and vomiting. Her temperature hit 105°, lead researcher on the case, Stephen Russell, told the Washington Post early Thursday morning.
“Thirty-six hours after the virus infusion was finished, she told me, ‘Evan has started shrinking,’” Russell said. Over the next several weeks, the tumor on her forehead disappeared completely and, over time, the other tumors in her body did, too.
Russell said he and his team had engineered the virus to make it more suitable for cancer therapy. And, after just one dose of it, Erholtz’s cancer went into remission. She has been completely cleared of the disease, Russell wrote in Mayo Clinic Proceedings. However this trial was successful on only one of the two patients.
Tanios Bekaii-Saab, a researcher at James Cancer Hospital and Solove Research Institute in Ohio, said the study must be confirmed in large randomized clinical trials — where many hopes get dashed, the Minneapolis Star Tribune reported.
“Unless we get to the third stage of development, we are cautiously optimistic,” he said. According to the clinic’s statement released Wednesday: In a proof of principle clinical trial, Mayo Clinic researchers have demonstrated that virotherapy — destroying cancer with a virus that infects and kills cancer cells but spares normal tissues — can be effective against the deadly cancer multiple myeloma. …
Using re-engineered viruses to fight cancer, oncolytic virotherapy, has a history dating back to the 1950s. Thousands of cancer patients have been treated with oncolytic viruses from many different virus families (herpes, pox, common cold, etc.). This study, however, provides the first well-documented case of a patient with disseminated cancer having a complete remission at all disease sites after virus administration.
“What this all tells us is something we never knew before – we never knew you could do this in people,” Russell said. “It’s a very important landmark because now we know it can happen. It’s a game changer. And I think it will drive a development in the field.”
The Star Tribune explained how it works: [Viruses] bind to tumors and use them as hosts to replicate their own genetic material; the cancer cells eventually explode and release the virus. Antiviral vaccines that have been rendered safe can produce the same effects and can also be modified to carry radioactive molecules to help destroy cancer cells without causing widespread damage to healthy cells around the tumors. The body’s immune system then attacks any remaining cancer that carries remnants of the vaccine’s genetic imprint.
Russell said the trial taught the medical researchers two things: “No. 1, you need a really big dose and No. 2, the patient needs to not have an antibody to the virus.”
Russell said the treatment worked in Erholtz, whose tumors were mostly in her bone marrow. However, it was unsuccessful in the other patient, whose tumors were mainly in her leg muscles, the Star-Tribune reported. He said more research is needed to know how the nature of the tumor affects the virus.
The next step for this method is another clinical trial, which is expected to launch by September, to see if the massive measles dose works on a large number of patients.