One intravenous dose of the measles vaccine enough to inoculate 10 million people from the disease seems to have treated 50-year-old Stacy Erholtz’s otherwise untreatable cancer, according to a case report published Wednesday in the journal Mayo Clinic Proceedings.
Erholtz, of Pequot Lakes, Minn., was enrolled in a clinical trial nearly a year ago at Mayo Clinic in a last ditch effort to treat a form of blood cancer in the bone marrow called multiple myeloma. She went into complete remission after receiving just one dose of the measles vaccine, the researchers report.
Erholtz was one of two subjects who took part in the experiment. The second patient, a 65-year-old woman, did not achieve the same results. However, the researchers said Erholtz’s case provides “proof of concept’’ that a single, large dose of intravenous viral therapy can kill cancer by overwhelming its natural defenses, while keeping surrounding healthy cells intact, Dr. Stephen Russell, a professor of molecular medicine who spearheaded the research at Mayo said in a public statement.
Even in the second patient, the researchers found that the vaccine fought some of the tumor cells.
The multiple myeloma has not recurred in the 11 months since Erholtz underwent the experimental treatment. However, a spokesperson for Mayo Clinic told Boston.com that she has had a tumor recurrence under the skin of her forehead unrelated to her initial diagnosis which was treated with localized radiation.
The research is a “benchmark to strive for and improve upon,’’ according to an accompanying editorial written by Dr. John C. Bell of the Centre for Innovative Cancer Research in Ottawa.
Researchers have long known that modified viruses have the potential to destroy cancer cells. The measles vaccine strain used in the trial was originally derived by a Mayo Clinic scientist in 1990. However, this study is the first to document the vaccine’s success in completely eliminating widespread tumors in a patient with advanced incurable cancer.
“The choice of MV [measles virus] as a therapeutic agent for myeloma was not happenstance, but rather the result of several years of thoughtful biological experimentation and rational virus engineering,’’ Bell wrote in the editorial.
Patients with multiple myeloma were chosen for the trial because they have a weakened immune system, so their bodies could not fight off the virus in the vaccine as it attacked the cancer cells, according to the researchers.
The treatment has only seemed to have an effect on only one patient and does not prove a cure for cancer.
The researchers now plan to launch a new phase of the trial in September that will explore the treatment method in a larger number of patients.