In the search for a cure for breast cancer, a major breakthrough has finally come. Biotechnology company Anixa Biosciences, Inc. announced earlier this month that its breast cancer vaccine, which is being designed with the help of the Cleveland Clinic, has completed phase 1 of its clinical testing. It will be moving forward to the next stages of development, and if all goes to plan, doctors may soon be able to stop cancerous tumors from forming.

“The vaccine is designed to mobilize the patient’s immune system to find, recognize, and destroy breast cancer cells for primary prevention,” Amit Kumar, Ph.D, CEO of Anixa Biosciences, Inc., tells Vogue. “If a patient is vaccinated and [their] immune system is trained to destroy the cancer cells when the cancer appears, the vaccinated immune system will destroy the cells before they can grow into a cell tumor.”

The vaccine, which comes in a set of three shots given to patients two weeks apart, specifically targets alpha-lactalbumin, a milk protein that is produced during lactation. It is typically not found after lactation in normal breast tissue, but scientists have found that the protein is expressed in about 70% of triple-negative breast cancer (TNBC) cases. The hope, Rima Patel, MD, oncologist and assistant professor in the division of hematology and medical oncology at Mount Sinai, explains, is that the vaccine can train people’s immune system to recognize the protein as harmful and attack it before it turns into cancer.

“It is designed to alert the immune system to attack a breast tumor, before it can develop or recur, and prevent it from growing,” says Dr. Patel. “It has been studied in an early phase 1 clinical trial in 35 women who had a history of early-stage TNBC and are at high risk of recurrence, and in patients without a history of cancer but are at high risk of developing breast cancer due to a genetic predisposition or other factors. The study thus far showed that the vaccine is overall well tolerated and resulted in an immune response in most patients.”

Research in mice shows that the vaccine has been successful in activating the immune system against alpha-lactalbumin and preventing breast tumors in these small creatures. While the vaccine shows promise in humans, Dr. Kumar says they have to test larger numbers and with control groups in the next phases to show its efficacy and safety.