Cancer Vaccine: Clinical Trials Induce Antibody Response

Susan Van Dusen

For breast cancer survivors, the possibility of their disease returning is a frightening reality. That’s why scientist Thomas Kieber-Emmons, Ph.D., has spent his career searching for ways to prevent recurrence and give patients a much-needed peace of mind.

His years of study have led to the development of a vaccine that is showing great potential not only to prevent the recurrence of breast cancer, but also to shrink tumors in other cancer patients.

The vaccine, which is a first of its type tested in humans, was shown to induce antibody responses that are toxic to breast cancer cells during a phase 1 clinical trial conducted with advanced-stage breast cancer patients at the UAMS Winthrop P. Rockefeller Cancer Institute.

The UAMS Cancer Institute and its affiliated Highlands Oncology Group in northwest Arkansas are the main facilities in Arkansas to offer phase 1 and phase 2 clinical trials, which are the early testing phases used by researchers to determine a new therapy’s safety, dosage and side effects. Before a drug can enter clinical trials the research must be approved by the FDA, which carefully monitors each phase of the trial to ensure sound scientific and ethical practices.

The trial of Kieber-Emmons’ vaccine was conducted exclusively with UAMS breast cancer patients, offering them access to a new therapy unavailable anywhere else in the world.

“The participants in our phase 1 trial had significant disease, including one whose cancer had metastasized to her brain. It looks like the vaccine in combination with her standard therapy had a positive impact in this patient in particular,” said Kieber-Emmons, professor of pathology in the UAMS College of Medicine.

The vaccine was shown to induce antibody responses that are toxic to breast cancer cells.
The phase 1 clinical trial, conducted at UAMS by Laura Hutchins, M.D., was primarily designed to evaluate how well patients tolerated the new vaccine, any adverse side effects and the effect on inducing immune responses that kill cancer cells in patients. A phase I trial enrolls a small number of patients, sometimes a dozen or fewer.

Kieber-Emmons’ collaborator on the study, Hutchins is professor in the Division of Hematology/Oncology in the UAMS College of Medicine and director of clinical research at the UAMS Cancer Institute.

Now in a phase 2 clinical trial, the vaccine is being tested in a greater number of patients at UAMS and Highlands to determine its effectiveness and safety. The vaccine is being tested in conjunction with chemotherapy in women with earlier stage disease to see if it helps trigger the tumor to shrink prior to surgery. A collaboration between UAMS and Highlands allows patients to receive the benefits of clinical trials while undergoing treatment close to home.

If it continues to show positive results, a phase 3 clinical trial will follow in which the vaccine will be used on hundreds or thousands of patients at multiple sites to compare its effectiveness with standard treatment. On average, it takes about eight years once a cancer drug has entered clinical trials for it to become FDA approved for widespread use.

In addition to its potential for breast cancer patients, the vaccine will be tested in inoperable lung cancer patients and plans are underway to test the vaccine in UAMS patients with melanoma and a type of brain cancer called glioblastoma.