FDA Approves First Immunotherapy Drug for Triple-Negative Breast Cancer


The U.S. Food and Drug Administration (FDA) has granted accelerated approval to the first immunotherapy treatment for breast cancer.

The treatment combines the drug atezolizumab (Tecentriq) with a form of chemotherapy.

This development is big news because the drug garnered the first positive phase 3 trial for an immunotherapy drug to treat breast cancer. The treatment was also first to show a substantial survival benefit for people with triple-negative breast cancer, one of the most aggressive forms of the disease.

Going forward, it opens the field to a large development program, Dr.Pete Schmid, PhD, one of the researchers from Queen Mary University of London, has said.

Tecentriq is the brand name of the immunotherapy drug atezolizumab. It has already been approved to treat specific types of urinary and lung cancers.

A study published last fall in the New England Journal of Medicine found that the therapy extended progression-free survival, which refers to a duration of time in which a person’s cancer doesn’t worsen.

Those who used the drug had a median progression-free survival of 7.4 months compared to 4.8 months for those who only received the chemotherapy with a placebo.

This is the first time immunotherapy has worked in such a difficult-to-treat cancer,” Schmid said in the statement.

Schmid said more research is needed to see if the drug could work on other types or earlier stages of breast cancer.

How it works

Atezolizumab is an antibody that attaches to a PD-L1, a protein in the cancer cells, explained Leisha Emens, PhD, a professor at the University of Pittsburgh Medical Center Hillman Cancer Center, who worked on the trial.

That protein is expressed almost exclusively with immune cells in a tumor. The drug binds to the PD-L1 protein and releases the immune cells in the tumor so they can fight the cancer. Chemotherapy is part of the treatment because it may decrease the burden of tumor the immune system has to fight and may boost the ability of the immune cells to attack the cancer.

With this approval, we now have a targeted agent for the treatment of triple-negative breast cancer, and this targeted agent engages the immune system.

People using this drug combination who respond to it may ultimately enjoy a longer response to the therapy due to activation of the immune system and the ability of the immune response to persis,” Emens said.

But this new drug comes with a hefty price tag, atezolizumab costs about $13,400 per month.

Dr. Amy Tiersten, a breast oncologist at the Dubin Breast Center at Tisch Cancer Institute at Mount Sinai in New York City, was thrilled about the drug’s approval and said it should be covered by insurance.

Why it got accelerated approval

The FDA’s accelerated approval is granted for certain drugs that treat serious conditions and fill an unmet need. The manufacturer of the drug is still required to conduct additional trials and is expected to submit more findings by September next year. Upon those results, the drug could garner traditional approval.

When breast cancer cell growth isn’t triggered by estrogen, progesterone, or human epidermal growth factor 2 (HER2), it’s known as triple-negative breast cancer. This type of breast cancer is considered aggressive with poor prognosis.

It doesn’t respond to hormonal cancer treatments that have helped improve survival rates for people with other forms of the disease. However, it does respond to chemotherapy, but cancer cells can develop a resistance to chemotherapy agents. The treatment can also be very difficult on the patient as it kills off healthy cells along with cancer cells.

Triple-negative breast cancer is most likely to affect Hispanic and African-American women, along with people who have the BRCA1 gene mutation. It can develop in women in their 40s and 50s.

Approximately 15 percent of breast cancers are triple-negative, the National Breast Cancer Foundation reports.

About one-fifth of people with triple negative breast cancer have the PD-L1 protein, which is what atezolizumab targets.