High-dose vitamin B3 is showing early promise against glioblastoma, one of the most aggressive brain cancers. An ongoing trial found 82.3 percent of patients progression-free at six months.

The Phase I/II study is being run at the University of Calgary. It was published on June 22, 2026, in the Journal of Neuro-Oncology. The trial is led by Drs. Gloria Roldan Urgoiti and Wee Yong of the Hotchkiss Brain Institute.

Patients with newly diagnosed glioblastoma received controlled-release niacin alongside surgery, radiation and chemotherapy. The interim analysis covered 24 evaluable patients. The 82.3 percent progression-free rate beat the historical benchmark of 53.9 percent for standard care alone.

The result exceeded the trial’s prespecified threshold, so it will continue to its target of 48 patients. The rationale is immunological. Niacin appears to reactivate immune cells that the tumour had suppressed.

Blood samples showed niacin shifted the immune profile toward an anti-tumour state. Memory CD8-positive T cells and natural killer cells increased.

Researchers stress the findings are preliminary. But in a disease with median survival around 15 months, the early signal stands out.