A bold cancer therapy that uses the polio virus to attack a form of brain cancer has been so successful, it's been given "breakthrough status" from the Food and Drug Administration (FDA).

The status means hundreds of patients can receive the treatment, before testing is even completed, or the FDA has finally given its approval— a process that can normally take years.

Glioblastoma is usually fatal within just months of diagnosis, but Duke University researchers developed the treatment that has resulted in quick and complete recoveries among patients in clinical trials.

This creates a whole new virus — PVS-RIPO — which can only grow by feeding on the abnormalities found in diseased cells. As a result, it destroys cancer cells while ignoring healthy ones.

Cells in the polio virus have a natural receptor that can attach to almost all tumor cells. This lets PVS-RIPO break into the cancer cells, and once inside, it strips tumors of their protections against the immune system.

The process unleashes the full power of the immune system directly against now-defenseless cancer cells.

One patient diagnosed with Glioblastoma in 2011 and treated with the therapy saw her tumor shrink for 21 straight months until it disappeared. Three years later, she is completely cancer-free. She was one of the patients featured on a recent news report on 60 Minutes.

(WATCH the video below from 60 Minutes) — Photo: 60 Minutes