Twenty Years On Seven Women with Metastatic Breast Cancer Still Alive After Experimental Vaccine
More than twenty years ago, seven women with metastatic breast cancer participated in a clinical trial at Duke University School of Medicine. They received an experimental immunotherapy at a moment when medicine offered very limited options for treating this advanced disease. Therapeutic possibilities for metastatic breast cancer were largely exhausted, and patients in this condition typically entered trials with little hope of long-term survival. The vaccine was an attempt to stimulate the immune system to recognize and control the tumor, without any guarantee of success.
In This Article:
The clinical trial
The vaccine was not a standard drug, but a personalized immunotherapy prepared from the patients’ own immune cells. It was designed to target HER2, a protein associated with aggressive forms of breast cancer. All seven women received the vaccine under a clinical protocol. At the moment of administration, physicians had no indication that the treatment would result in long-term disease control. The study was designed as an exploratory clinical trial, not as a potential standard of care. After completion of the protocol, the treatment was not continued, nor was the vaccine adopted into broader clinical use.
Years without attention
In the years that followed, the clinical trial largely disappeared from the focus of the medical community. There were no extended trial phases, no large follow-up programs, and no commercial development of the vaccine. The patients, however, continued with their lives. Some received additional therapies, some lived with chronic disease, but one fact remained unnoticed for years: none of the seven women died from their cancer.
The re-examination
Nearly two decades later, researchers at Duke Health revisited the data from the old clinical trial. The reason was simple and unusual: all seven women were still alive. In the context of metastatic breast cancer, such an outcome is exceptionally rare. This prompted the research team to investigate whether a shared biological mechanism could explain the long-term survival observed in all patients.
What the analyses revealed
When scientists examined the women’s immune systems, they found that even after more than twenty years, the patients still had active immune cells capable of recognizing HER2. Of particular interest were immune cells expressing the marker CD27, which is associated with long-lasting immune memory. These findings suggest that the vaccine may not have acted as a short-term treatment, but instead induced a durable change in how the immune system recognizes cancer. Researchers noted that this stable immune memory could have played a central role in controlling the disease over many years.
Why development did not continue
Despite this outcome, the vaccine was not further developed in the years that followed. Duke has not provided a single, definitive explanation for this. At the time, cancer vaccine approaches faced significant scientific, technical, and logistical limitations, and industry attention was focused on therapies that were easier to standardize and deploy. The fact that the outcome became evident only decades later further complicated efforts to establish a clear cause-and-effect relationship under the clinical standards of that period.
The questions being asked today
The fact that all seven women survived for more than 18–20 years has reopened questions about the role of vaccines in cancer treatment. Why was this clinical signal not followed by larger studies? Why did the vaccine remain confined to a single, small trial? And does modern oncology, with today’s immunotherapy tools, finally have the capacity to continue where this story stopped? This is not a story of a finished solution. It is a story of a result that does not fit expectations — and therefore demands answers.
