Idit Sagiv-Barfi Delivers TEDx Talk on the Latest Cancer Vaccine

Idit Sagiv-Barfi, MD, PhD

Idit Sagiv-Barfi, PhD, an instructor of oncology, opens her TedxPaloAlto talk with this: “Our immune system is amazing. Not only does it have the ability to protect our bodies against harmful viruses and bacteria, it also protects our body against cancer.” She fills the remainder of the talk – "Cancer Vaccine: Seek, Destroy and Remember" – with evidence of exactly how the immune system can fight cancer. Specifically, she describes her own attempt to develop a cancer vaccine that teaches the body how to shrink and prevent tumors.

Cancer vaccines, says Sagiv-Barfi, start with the same idea as traditional vaccines, which “program our immune system to detect and recognize” a specific pathogen. They do this both by activating an antibody response that signals immune cells to come and destroy the pathogen and by generating memory cells that respond to future encounters with the pathogen by launching a stronger and faster response.

A key difference between cancer vaccines and pathogen vaccines, however, is timing. Sagiv-Barfi says, “The pathogen vaccine is given before the onset of the disease. Our therapeutic cancer vaccine is given after the tumor is detected.” Still, just like with the pathogen vaccine, “the most important thing is the generation of memory cells. But now the memory is not against the pathogen. It’s against the cancer.”

In this talk, Sagiv-Barfi describes how she and her colleagues found the right molecules to use in the vaccine and then tested them in different models: “When we combined CPG and anti-OX40 in the same syringe and injected it directly into one of the tumors not only did the treated tumor completely regress but also the non-treated tumor went away. The mice were completely cured.” Three months later, they injected those same mice with the original tumor cells to test further the vaccine. Sagiv-Barfi reports, “None of the mice developed tumors. They were all resistant to this cancer. They all had memory of this tumor.”

After testing additional models, Sagiv-Barfi says the research was able to more closely address what can happen with humans, where tumor cells are more heterogenous and develop spontaneously. As a result, the first clinical evaluating this particular immunotherapy (the combination of CPG and anti-OX40 in patients with non-Hodgkin lymphoma) is underway.