Washington: A new experimental vaccine drastically extends the life of patients with the most deadly type of brain tumour, glioblastoma (GBM), according to a small-scale US study published Monday.
The vaccine targets an aggressive cancer gene called EGFRvIII that fuels glioblastomas, researchers said, adding that in their study of 18 patients, survival was extended from an expected 15 months to 26 months.
The study published in the Journal of Clinical Oncology also said the vaccinated patients benefited from a longer "progression-free survival period, 14.2 months, compared to 6.3 months for those who did not receive the vaccine".
Results of the study showed the vaccine "eliminated all of the cancer cells carrying this marker in all but one of our study participants," said study author Darell Bigner of the Preston Robert Tisch Brain Tumour Centre at Duke University in Durham, North Carolina.
In total, 35 patients participated in the study, including 17 patients with GBM who were in a control group and did not receive the vaccine.
All of the participants received surgery, radiation and the chemotherapy drug temozolomide, and then patients in the vaccine group "began receiving injections one month after completing radiation and stayed on the vaccine as long as it appeared to be working," said the study.
Researchers found the vaccine stimulated an immune response in approximately half the patients vaccinated.
Glioblastoma is the most common form of brain cancer with roughly 10,000 new cases arising in the United States each year, and the forecast for diagnosed patients is grim -- they live on average just over one year after the first diagnosis.
The data suggest that these responses are linked to increased survival time, "but the numbers are so small that we can not conclude this with any degree of certainty," said co-author Amy Heimberger, of MD Anderson Cancer Centre at the University of Texas in Houston, and she urged further studies.