by Tom Wilemon
Vanderbilt-Ingram Cancer Center is launching a clinical trial that pairs an experimental vaccine with an established immunotherapy for recurrent, human papilloma virus (HPV)-related oropharyngeal cancer of the head and neck.
This novel vaccine, PVX7, is made by PapiVax Biotech Inc., and the immunotherapy is pembrolizumab made by Merck. The combination is intended to stimulate a greater anti-cancer immune response than either therapy used as a stand-alone treatment.
Michael Gibson, MD, PhD, associate professor of Medicine at Vanderbilt-Ingram, is the principal investigator.
“This therapeutic vaccine is designed to activate the immune system to recognize and kill the cancer cells, like pushing the gas pedal down. However, stepping on the gas is not the only thing needed to activate the immune system against cancer. Unfortunately, the cancer can also put the brakes on this immune response. To overcome this limitation, like releasing the parking brake, we combine vaccination with the immune checkpoint inhibitor pembrolizumab. By using both approaches — stepping on the gas and releasing the parking brake, the combination may more effectively target the immune system against the cancer,” Gibson said.
Vanderbilt-Ingram treats more people with head and neck cancers than any other cancer center in the United States and has a patient volume of more than 1,000 a year. That patient volume, combined with the expertise of Vanderbilt-Ingram Head and Neck Cancer Program members and investigators, led the vaccine developers to ask Gibson to lead the trial. It seeks to enroll 54 patients at Vanderbilt-Ingram and two other sites — the Rogel Cancer Center at the University of Michigan and the Mayo Clinic in Scottsdale, Arizona.
“HPV-related cancers are a subset of all head and neck cancers and are on the rise. Although most patients are cured with multi-modality care, a limited fraction of patients will recur,” Gibson said. “This group of patients, although uncommon, are targeted by our trial. We involved our colleagues at Mayo and Michigan because of their expertise and with the goal of improving accrual and getting an answer sooner.”
The objectives of this phase 2 clinical trial are to test the safety of the vaccine when combined with pembrolizumab as well as response rate, overall survival and safety. All participants will receive the combination therapy.
The experimental vaccine in the trial, PVX7, is intended as a therapeutic vaccine for established cancer. This is different than vaccines (such as Gardasil) that prevent cancer, Gibson noted. HPV preventive vaccines are 97% effective in preventing cervical cancer, according to the American College of Obstetricians and Gynecologists, but cannot be used to treat cancer.
For more information about this study, contact Cancer Care at Vanderbilt-Ingram Cancer Center (615-936-8422) or refer to ClinicalTrials.gov Identifier: NCT05799144.
