Scientists at the Mayo Clinic are starting a second round of human clinical trials to test if an engineered strain of measles virus is an effective cancer treatment. The trial follows a successful first round of tests where a woman went into complete remission after a massive dose of the virus eradicated cancer in her body. Ben Gruber reports.
Stacy Erholtz has been cancer free for more than a year. She has a doctor armed with an experimental virus to thank for it. SOUNDBITE (English) STACY ERHOLTZ, CANCER SURVIVOR AND TRIAL PARTICIPANT, SAYING: "I have just not felt this good in so long, I don't remember feeling so well." In 2004 Stacy was diagnosed with multiple myeloma, a blood cancer that forms in plasma cells. Despite multiple treatments, like chemotherapy and stem cell transplants, her cancer always returned. But Stacy's failure to respond to conventional treatment made her the perfect candidate for an experimental one - oncolytic viral therapy - a treatment that uses a virus to hunt down and kill cancer in the body. In myeloma patients, Dr. Stephen Russell saw a window of opportunity. SOUNDBITE (English) DR. STEPHEN RUSSELL, PROFESSOR OF MOLECULAR MEDICINE, MAYO CLINIC, SAYING: "This particular form of cancer, multiple myeloma, is associated with the loss of antibodies against viral infections you've previously had. So many of the patients who have myeloma who have had a great deal of previous therapy and have run out of options, they have no detectable measles antibody in their blood." And with no antibodies, Russell's weaponized virus can target and kill cancer cells in the body, a process which in turn kick-starts the immune system to also attack the cancer. In initial trials, the virus proved ineffective and that's when the doctors upped the dose - significantly. SOUNDBITE (English) STACY ERHOLTZ, CANCER SURVIVOR AND TRIAL PARTICIPANT, SAYING: "They didn't put it in relatable terms which was beautiful for me. I said don't do that - people don't need to know that they are getting enough measles to vaccinate 10 million people." Stacey's initial response to this dose was a dangerously high fever and extreme vomiting. But by the next morning a golf ball sized tumour that had protruded from her forehead started shrinking. Within 36 hours... it was gone. SOUNDBITE (English) DR. STEPHEN RUSSELL, PROFESSOR OF MOLECULAR MEDICINE, MAYO CLINIC, SAYING: "Over the next few weeks everything disappeared. We couldn't find any myeloma in her bone borrow. The repeat CT scans gradually over the next few months became fainter and fainter until we couldn't see anything. " (SOUNDBITE) (English) STACY ERHOLTZ, CANCER SURVIVOR AND TRIAL PARTICIPANT, SAYING: "I was lit up like a Christmas tree and then the colours just started to fade to black..I am clean and clear. No sign of cancer. " A second phase human clinical trial his now underway at the Mayo Clinic. Dr. Russell says engineered viruses will eventually change the way all types of cancers are treated. The job now is to find the most efficient path to allow killer bugs to tackle a killer disease.