T cell therapy shows promise in treating aggressive brain cancer

A new phase 1 clinical trial has shown promising results for an immunotherapy in treating recurrent glioblastoma, a highly aggressive and fatal brain cancer. This treatment involves chimeric antigen receptor T (CAR-T) cell therapy, which modifies a patient's T cells to better recognize and destroy cancer cells. The trial, published in Nature Medicine, focuses on CAR-T cells trained to target a protein called B7-H3, which is prevalent in most glioblastomas.

Researchers tested three doses of the treatment in a small group of patients whose cancer was not responding to standard therapies. They found that participants tolerated the therapy well and identified a recommended dose for future research. More than half of the participants experienced stable or reduced tumor size for up to three years after treatment, including one patient who remained in complete remission.

B7-H3-targeting CAR-T cell therapy could provide new hope for patients with treatment-resistant recurrent glioblastomas who currently have few options. Lieping Chen, one of the study's co-principal investigators, expressed excitement about finding treatments for currently untreatable cancers. The study's collaborators included a neurosurgical team at Beijing Tiantan Hospital and a team from Tcelltech, a biotech company.

Glioblastoma is typically treated with surgery and chemotherapy, but the cancer often returns in an even more aggressive form. The median life expectancy for patients with recurrent glioblastoma is less than a year. Scientists have been exploring B7-H3 as a target for new cancer therapies since its discovery in 2001, though its prevalence in tumors remains unclear.

The trial involved biopsying tumors to ensure they expressed B7-H3, drawing blood from participants, and enriching their T cells. The modified T cells, called CAR-T cells, were introduced to recognize B7-H3 and attack cancer cells. Injecting the cells directly into the tumor site through a catheter helped bypass the blood-brain barrier, which often prevents other therapies from effectively treating glioblastomas.