One of those trials is still taking patients on Long Island at Stony Brook's Cancer Center.
It includes a 41-year-old woman who, 6 years ago, had her first battle with breast cancer.
This is now her 3rd phase to try to keep cancer away.
If the trial works, this is a major advancement in fighting cancer.
Christina Amitrano is part of something that could save lives.
Stony Brook University Hospital is the only site on Long Island that's part of a worldwide phase 3 clinical trial called FLAMINGO-01, for a new breast cancer vaccine.
"If it's successful, then it will become the standard of care," Amitrano said.
When she was just 35, she was diagnosed with stage 2 triple-positive breast cancer.
"It's a very aggressive type of cancer, and the HER2-positive aspect of it, makes it more aggressive," Amitrano said.
There are many different clinical trials going on right now for breast cancer vaccines.
This particular vaccine for HER2-positive patients like Christina is from a company called Greenwich LifeSciences near Houston.
On their website, it says so far their trial shows an 80 percent or greater reduction in metastatic breast cancer recurrence over 5 years of follow-up.
That's compared to a reduction rate of no more than 50 percent from other approved products and no serious side effects.
Christina's oncologist says the idea is to harness the patient's immune response to fight cancer.
"So patients are injected with essentially a little piece of the HER2 protein with what's called an immune adjuvant, to sort of stimulate the immune system," Dr. Jules Cohen at Stony Brook Cancer Center said.
As for Christina, she doesn't yet know if she's received the vaccine or the placebo. What she does know is participation matters.
"Say, you know, 25 out of every 100 women recur for a given type of breast cancer..And, we reduce that from 25 to say 10 percent that means we've saved 15 lives for every hundred people that we treat," Cohen said.
To learn more, contact the Stony Brook Medicine Clinical Trials Office at (631) SB-TRIALS (631) 728-7425 or CancerClinicalTrials@stonybrookmedicine.edu.