Dr Daniel George on the Challenge of Cancer Vaccines

Although Daniel George, MD, of the Duke Cancer Institute, sees value in cancer vaccines and expects they will start showing more benefit to patients, he acknowledges that a barrier to widespread use of cancer vaccines is that they don't show an immediate response.

Transcript

What is your outlook on cancer vaccines, and what do you think has been a barrier to preventing widespread use?

So immunotherapy is exciting because of the checkpoint inhibitors, but let's not forget that there is absolutely more to the immune system than PD-1, PD-L1 target. And I personally believe that cancer vaccines will show more and more benefit in the future in patients. In prostate cancer we have the sipuleucel-T strategy, which is a cancer vaccine of sorts, where we're activating autologous antigen-presenting cells to stimulate the immune system. And I do see a role for both stimulating the immune system as well as releasing checkpoints in combination or in sequence in the future.

I think one of the problems has been that with vaccines they take time to work. And because of that we don't typically see an immediate response. And in oncology, we're kind of trained to a culture of looking for a response to agents to guide our practice, whether it be chemotherapy, hormonal therapy, or even now checkpoint inhibitors. So I do see that as somewhat of a stumbling block in being able to show the value.

Ultimately, vaccines should show an improvement in overall survival, of disease-free survival in the adjuvant setting, or what have you. So I do look forward to them in the future, but I think they're going to take longer, slower trials to show their benefit.