Cleveland Clinic Launches Trial Examining Preventive Vaccine for TNBC

G. Thomas Budd, MD

Cleveland Clinic has partnered with Anixa Biosciences, Inc. to open a phase 1 trial examining a vaccine aimed at preventing the development of triple-negative breast cancer (TNBC), according to a press release.¹

The study will determine the maximum-tolerated dose of the vaccine in patients with early-stage TNBC, as well as characterize and optimize the body’s immune response to it.

“We are hopeful that this research will lead to more advanced trials to determine the effectiveness of the vaccine against this highly aggressive type of breast cancer,” principal investigator G. Thomas Budd, MD, of Cleveland Clinic’s Taussig Cancer Institute, said in a press release. “Long term, we are hoping that this can be a true preventive vaccine that would be administered to healthy women to prevent them from developing triple-negative breast cancer, the form of breast cancer for which we have the least effective treatments.”

Because TNBC has biologic characteristics that often do not respond to hormonal or targeted therapies, the disease accounts for a disproportionally high number of breast cancer deaths, and there remains an urgent unmet need for more effective treatments. Moreover, TNBC is significantly more likely to occur in African American patients, and approximately 70% to 80% of tumors that occur in women with BRCA1 mutations in TNBC.

As such, the investigational vaccine under examination in the phase 1 clinical trial will target α-lactalbumin, a breast-specific lactation protein, which is not found post-lactation in normal, aging tissues, but is present in most TNBC. By activating the immune system against this protein, a preemptive immune protection against emerging breast tumors that express α-lactalbumin can be developed.

Additionally, the vaccine will contain an adjuvant that activates an innate immune response and allows the immune system to prevent the growth of these tumors.

“This vaccine approach represents a potential new way to control breast cancer,” Vincent Tuohy, PhD, the primary inventor of the vaccine and staff immunologist at Cleveland Clinic, said in a press release. “The long-term objective of this research is to determine if this vaccine can prevent breast cancer before it occurs, particularly the more aggressive forms of this disease that predominate in high-risk women.”

The study will enroll 18 to 24 patients who completed treatment for TNBC that are considered cancer-free but at high-risk for recurrence. Patients will receive 3 vaccinations every 2 weeks and be closely monitored for adverse effects and immune response. The estimated completion date is September 2022.

Subsequent research is anticipated to include healthy, cancer-free patients who are at high risk for developing breast cancer, and who have undergone voluntary bilateral mastectomy to lower their risk. These patients often harbor BRCA1/2 mutations or have a hereditary increased risk of developing breast cancer. 

Preclinical research demonstrating the safety and efficacy preventing breast tumors by activating the immune system against the α-lactalbumin protein in mice served as the basis of this phase 1 study. The research, which was published in Nature Medicine, found that a single vaccination could prevent breast tumors from developing in mouse models, as well as inhibit the growth of existing tumors.²

“This vaccine strategy has the potential to be applied to other tumor types. Our translational research program focuses on developing vaccines that prevent diseases we confront with age, like breast, ovarian and endometrial cancers,” Touhy said. “If successful, these vaccines have the potential to transform the way we control adult-onset cancers and enhance life expectancy in a manner similar to the impact that the childhood vaccination program has had.”

References

1. Cleveland Clinic Launches first-of-its-kind preventive breast cancer vaccine study. News release. Cleveland Clinic. October 26, 2021. Accessed November 29, 2021. https://cle.clinic/3HYcQcp
2. Jaini R, Kesaraju P, Johnson J, et al. An autoimmune-mediated strategy for prophylactic breast cancer vaccination. Nat Med. 2010;16(7):799–803. doi:10.1038/nm.2161