Researchers from Mass General Brigham and Dana-Farber Cancer Institute have developed a new treatment for glioblastoma, a highly aggressive brain cancer that often resists immunotherapy.
The therapy uses a genetically engineered herpes simplex virus that selectively infects and kills tumor cells while sparing healthy brain tissue. As it replicates, the virus destroys cancer cells and spreads through the tumor. It also stimulates the immune system by attracting cancer-fighting T cells into the tumor, turning a typically “cold” tumor into a “hot” one.
In a Phase 1 trial of 41 patients with recurrent glioblastoma, the treatment showed improved survival compared to historical outcomes. Researchers observed strong T cell infiltration in tumors, and patients lived longer when these immune cells were closer to cancer cells. The best responses were seen in patients with pre-existing immunity to the virus.
The findings suggest this approach could open new possibilities for immunotherapy in brain cancers, where treatment advances have been limited for decades.