Immunotherapy assists your immune system in identifying cancer cells as a threat to your body. Most initial cancer starts are recognized and eliminated by the immune system, and you will never even know they existed. But sometimes a cancer will persist and become clinically recognizable as a result of mutations during the development of the disease that allow it to evade immune surveillance. This allows the cancer to spread and go undetected.
The vaccine technology, licensed exclusively by Perseus, has gone through completed Phase I FDA clinical trials for the treatment of melanoma, renal cell carcinoma and neuroblastoma.
There have been encouraging results in clinical tests on human patients as shown in this chart.
The American Cancer Society has said that personalized therapies like the PCI vaccine "hold some promise as they take into account the complex molecular composition of gene expression profiles of individual tumors."
ACS Cancer Facts and Figures, 2012, p.33
Here are some resources where you can learn more about immunotherapy's role in cancer treatment: