A Breakthrough in Cancer Prevention: New Vaccines Show Promise Against Aggressive Cancers

Scientists are making remarkable progress in developing vaccines that could prevent cancer from occurring in the first place. Two major clinical trials are testing innovative approaches to stop aggressive cancers—triple-negative breast cancer and lung cancer—by training the immune system to recognize and destroy abnormal cells before they become malignant.

How Do These Cancer Prevention Vaccines Work?

Unlike traditional vaccines that protect against infections, these experimental vaccines target proteins found on cancer cells. The triple-negative breast cancer vaccine focuses on a protein called α-lactalbumin, which appears in about 70% of these aggressive tumors but disappears from normal breast tissue after women stop breastfeeding. The lung cancer vaccine, called LungVax, targets "red flag" proteins called neoantigens that appear on cells undergoing cancer-causing changes.

"Triple-negative breast cancer remains one of the most challenging forms of the disease to treat effectively," said Dr. G. Thomas Budd of Cleveland Clinic's Cancer Institute, who led the breast cancer vaccine study.

What Are the Early Results Showing?

The Cleveland Clinic's Phase 1 trial of the breast cancer vaccine included 35 participants across three groups: women who had completed treatment for early-stage triple-negative breast cancer, cancer-free individuals with genetic mutations that increase breast cancer risk, and patients with residual cancer cells after treatment. The results were encouraging:

• Immune Response: 74% of all participants developed an immune response to the vaccine, suggesting their bodies learned to recognize the target protein
• Safety Profile: The vaccine was well-tolerated with only mild side effects, primarily skin inflammation at the injection site
• Maximum Dose: Researchers determined the highest safe dose for future trials

For context, triple-negative breast cancer affects only 10-15% of breast cancer cases but causes a disproportionately high number of deaths. It's twice as common in Black women and accounts for 70-80% of breast tumors in patients with BRCA1 gene mutations.

What Makes These Vaccines Different from Cancer Treatments?

These preventive vaccines represent a fundamentally different approach from existing cancer therapies. Instead of treating cancer after it develops, they aim to stop it from forming. The lung cancer vaccine, LungVax, uses technology similar to the Oxford/AstraZeneca COVID-19 vaccine to deliver genetic instructions that help the immune system identify abnormal cells.

"The purpose of LungVax is to get the immune system to recognize these abnormal cells early and destroy them before they start to change towards cancer," explained the research team. This approach could be particularly valuable for lung cancer, which remains the leading cause of cancer death in the UK, with only 1 in 10 people surviving 10 years or more after diagnosis.

The breast cancer vaccine trial included Chase Johnson, a 36-year-old from North Carolina who was diagnosed with triple-negative breast cancer in 2021. After completing intensive treatment including chemotherapy, surgery, and radiation, she enrolled in the trial to prevent recurrence. "I am literally doing anything possible to make sure this doesn't come back," Johnson said.

What Happens Next in These Trials?

Both vaccine programs are moving toward larger Phase 2 trials. The breast cancer vaccine's Phase 2 study is expected to begin late next year and will be the first to examine whether the vaccine actually reduces recurrence risk, not just immune response. The lung cancer vaccine trial, funded with up to £2.06 million, is expected to begin in summer 2026 and will focus on people at high risk, including those previously treated for early-stage lung cancer and participants in lung cancer screening programs.

"Whether this immune response will translate into reducing the risk of recurrence or preventing breast cancer, we don't know that yet," acknowledged Dr. Budd, emphasizing that these are still early-stage results. However, the foundation for these vaccines comes from years of research, including Cleveland Clinic's work on the α-lactalbumin protein and Cancer Research UK's TRACERx study, which has been mapping the genomic changes in lung cancer development since 2014.