Duke University reports a personalized mRNA vaccine triggers tumor regression in four of ten glioblastoma patients in a first-in-human Phase I trial.
Duke University researchers have reported encouraging results from the first-in-human trial of a personalized mRNA vaccine targeting glioblastoma multiforme, the most aggressive and lethal form of brain cancer. Published in Science Translational Medicine, the Phase I study demonstrated that the vaccine triggers robust anti-tumor immune responses, with four of ten patients experiencing measurable tumor regression.
Glioblastoma carries a median survival of just 15 months from diagnosis, and the five-year survival rate remains below 5% despite decades of research. Standard treatment involves surgery, radiation, and temozolomide chemotherapy, but recurrence is nearly universal.
The personalized vaccine is created by sequencing the genetic mutations unique to each patient's tumor. An mRNA construct encoding up to 20 tumor-specific neoantigens is then synthesized and encapsulated in lipid nanoparticles. When injected, the patient's immune cells translate the mRNA into proteins that train the immune system to recognize and attack the cancer.
Dr. Matthias Gromeier, who led the research, noted that the blood-brain barrier has historically made brain cancers particularly resistant to immunotherapy. However, the mRNA vaccine approach stimulates a systemic immune response that includes T cells capable of crossing the blood-brain barrier and infiltrating the tumor microenvironment.
Imaging studies showed that four patients experienced tumor shrinkage of 20% or more, sustained for at least six months. Two additional patients showed disease stabilization. All ten patients tolerated the vaccine well, with side effects limited to mild fever and fatigue typically lasting 24 to 48 hours.
Molecular analysis of post-vaccination tumor samples revealed extensive T cell infiltration, confirming that the immune response generated by the vaccine successfully targeted the brain tumor. The infiltrating T cells were specifically reactive against the neoantigens encoded in each patient's personalized vaccine.
A Phase II trial is being designed to test the vaccine in combination with immune checkpoint inhibitors, which may further enhance the anti-tumor response. The trial will enroll 100 patients across 15 cancer centers in the United States and Europe.
The approach represents a convergence of mRNA technology, tumor genomics, and immunology that could potentially be applied to other cancers with high mutation burdens. Researchers at several institutions are already adapting the platform for pancreatic and lung cancers.