A team of researchers at the University of Washington School of Medicine has been working on a vaccine to fight one of the deadliest cancers across the globe, i.e. breast cancer for the last 20 years.
Phase 1 of the trial
In their recently published study in the medical journal JAMA Oncology, they revealed that in their phase 1 clinical trial 80% of the 66 women with advanced-stage metastatic breast cancer that received the vaccine were still alive by the trial’s end. This is a massive success considering only half of the patients with similar stages of breast cancer survive after five years.
The study, published in JAMA Oncology, analyzed the efficacy of three different doses of a plasmid-based vaccine that encodes ERBB2-specific type 1 T cells into the intracellular domain (ICD). ERBB2-Specific type 1 T cells, previously known as HER2-specific type 1 T cells, are known to target HER2. HER2, human epithelial growth factor receptor 2, is found on the cell surface. In approximately 30% of breast cancers, HER2 is overproduced, making these cancers more aggressive and likely to recur.
According to the study in JAMA Oncology, “The vaccine was administered intradermally once a month with a soluble granulocyte–macrophage colony-stimulating factor as an adjuvant for three immunizations. Toxicity evaluations occurred at set intervals and yearly. Peripheral blood mononuclear cells were collected for evaluation of immunity.”
Patients were followed for a median follow-up of 10 years; however, follow-ups ranged from 3 to 13 years. Given the data, researchers determined that the vaccine was safe for patients. The vaccine’s side effects resembled the COVID vaccine, the most common being injection site pain or redness, fever, chills, and other flu-like symptoms.
In addition to being tolerable, the vaccine triggered a cytotoxic immune response as the researchers had anticipated.
How do vaccines compare to radiation and chemotherapy?
Vaccines are a more targeted way to treat breast cancer than radiation and chemotherapy. They focus on killing cancer cells without harming healthy ones.
By contrast, chemotherapy kills quickly dividing cells — both cancer cells and some healthy cells like hair and immune cells. That’s why it causes side effects like hair loss, infections, and mouth sores.
If the results from the new randomized controlled ongoing phase 2 trial of the vaccines are equally promising, it will be a strong signal for us to move forward to a definitive phase 3 trial making this new vaccine a groundbreaking discovery in the field of modern medicine.