Cancer Vaccines — Hope or Hype?
28 July, 2022You’ve had the COVID vaccine and been boosted. You’ve been vaccinated against measles, mumps and rubella. You’ve likely had a tetanus shot. You’re protected from chicken pox. Maybe you’re one of those people who gets a flu shot every fall. But have you been vaccinated for cancer?
Wait. What? There are vaccines for cancer?
We all have a basic understanding of how vaccines work. Weakened or dead germs, such as a virus or bacteria, are introduced into a healthy person’s body in order to invoke an immune response in the body enabling the immune system to ramp up its defenses and better protect the person from getting the disease or infection.
Cancer vaccines work in much the same way, except therapeutically instead of prophylactically, by either enabling the person’s immune system to attack cancer cells, or by preventing infection from viruses that are known to cause cancer.
Vaccines that Prevent Cancer
Some cancers are known to be caused by viruses. For example, some strains of the human papillomavirus, or HPV, have been linked to cervical, anal, throat, vaginal, vulvar, and penile cancers. In fact, according to the American Cancer Society, most cervical cancers are caused by infection with HPV. Vaccinating children and young adults against HPV helps protect against cervical cancer and the other 5 cancers HPV can cause.
Another virus known to cause cancer is Hepatitis B, or HBV. People who have chronic (long-term) infections with the Hepatitis B virus are at higher risk for liver cancer. Therefore, getting the vaccine to help prevent HBV infection may lower the risk of getting liver cancer.
These are two examples of preventative vaccines that target viruses known to cause certain cancers. They don’t target cancer cells directly because the cancer cells don’t yet exist in the body. But most cancers, including colorectal, lung, prostate, and breast cancers, are not thought to be caused by infections. Though many groups are looking towards very early detection of cancer and an attractive way to prevent non-viral cancers would also be some type of preventive vaccine.
Vaccines that Treat Cancer
Cancer treatment vaccines are different from preventative vaccines that work against viruses known to cause cancer. Cancer treatment vaccines are designed to trigger the immune system to mount an attack against cancer cells in the body.
Cancer vaccines of this type have one of the longest histories in the field of Immunotherapy, going back to the days when the field now known as Immuno-Oncology was known as Tumor Immunology. The field has driven, and benefitted from, advances around target/antigen identification (such as most recently neoantigens), adjuvants, and an array of immunization platforms, including peptides, Oncolytic Viruses, and lately, mRNA. But what has really enabled the field to be reenergized over the past decade has been the approval of the checkpoint inhibitors, unlocking the immunosuppressive tumor microenvironment (TME), and allowing immune cells to see and react to exogenous (and/or endogenous) antigens. And yet, while the experimental models continue to demonstrate great preclinical proof of concept, the translation in clinical trials into patient benefit, not just immune responses, has been modest at best.
To date there is really only one true cancer vaccine approved by the FDA.
- Provenge, approved a decade ago, is an immunotherapy used to treat advanced prostate cancer. Provenge is a cellular immunotherapy that is customized to each individual by using his own immune cells to target a key protein expressed on prostate cancer cells.
This then begs the question: Why has the field not progressed as fast and as far as many insiders might have hoped? And why have the responses in animal models not been able to be similarly demonstrated in human cancer patients?
To take a deep dive into this field, ShareVault invited Jeff Bockman, PhD, EVP, Oncology Practice Head of Lumanity BioConsulting, to present a webinar on August 25, 2022. Dr. Bockman and Dr. Lisa Butterfield, PhD, Adjunct Professor at UCSF, will explore the fascinating world of therapeutic cancer vaccines, what the hurdles are, and what the future holds. Lisa and Jeff will explore the current science, what’s going on in the clinic, and what stumbling blocks impede progress, and how researchers, Oncologists and industry professionals can best obviate these stumbling blocks in order to finally see cancer vaccines realize their true potential.