Most traditional vaccines, like the flu shot, use inactivated or weakened viruses that once injected into the body stimulate an immune response that can later protect against infection. There are also protein vaccines, such as the Hepatitis B and HPV vaccines, that deliver the part of the virus that stimulates a protective antibody response. Developing these vaccines is a complicated process that requires much time and money. Vaccines based on Messenger RNA, or mRNA, do not have these problems. Instead of using the virus, they contain genetic material that instructs the body to develop defenses against future infection. These vaccines can be produced quicker and cheaper than traditional ones.
The success of the COVID-19 vaccine took mRNA technology from the laboratory to the spotlight, and Moffitt researchers are now preparing for a first-of-its-kind cancer vaccine trial this spring for head and neck cancer.
The study, which is part of a larger national trial, is headed by Kedar Kirtane, MD, a medical oncologist in Moffitt’s Head and Neck Oncology Program. It will determine the safety and efficacy of an mRNA vaccine for head and neck cancer patients with recurrent or metastatic disease in combination with pembrolizumab, a checkpoint inhibitor.
“We will take a tumor sample and sequence it to look for the unique cancer markers. Then we will create a vaccine to target them,” said Kirtane. “It really is as personalized as you can get.”
While there currently are two approved immunotherapy treatments for head and neck cancers, only about 20% of patients respond. Vaccine trials like this one will hopefully open the opportunity to satisfy a critical unmet need in this patient population.
“The biggest thing thus far that has made me happy about the COVID-19 vaccines is the safety,” Kirtane said. “RNA vaccines have been studied for a while, but we haven’t seen mass use of them. So, the fact there’s all this data suggesting safety really is the first big thing.”
Regardless of how they’re made, cancer experts believe vaccines could have a major impact on fighting the disease. The important thing is to keep studying them to determine if they need to be combined with other treatments and find the best timing for administration.