Nav: Home

Immunotherapy drug effective for metastatic triple negative breast cancer

June 03, 2017

The immunotherapy drug pembrolizumab--already FDA-approved for other forms of cancer-has been found to be effective in patients with metastatic triple negative breast cancer, according to an international clinical trial led by NYU Langone's Perlmutter Cancer Center.

The trial investigated the drug in two separate cohorts of patients: Cohort A, which included 170 patients with heavily pretreated metastatic triple negative breast cancer (mTNBC) regardless of PD-L1 expression, and Cohort B, which included 52 patients with PD-L1-positive tumors who received it as first-line therapy.

In Cohort A, pembrolizumab shrunk tumors by more than 30 percent in eight of 170 patients, or five percent, and stabilized the disease in 35, or 21 percent, of those previously treated for mTNBC. Of the eight who experienced tumor reduction, all of them lived at least another year. The remaining patients in this cohort had a lower chance of survival.

In Cohort B--those who received pembrolizumab as first-line therapy--12 of 52 patients, or 23 percent, saw tumors shrink by more than 30 percent, while the disease was stabilized in nine of them, or 17 percent.

Sylvia Adams, MD, associate professor of medical oncology at Perlmutter Cancer Center and principal investigator of this study, presented the findings on June 3 in Chicago at the annual meeting of the American Society of Clinical Oncology. This multi-site trial was conducted at 17 medical centers across four continents.

Adams points out that Cohort A is the first phase II study of an immunotherapy for triple negative breast cancer to be reported and represents the largest cohort of patients with mTNBC treated with immunotherapy to date.

"Our results suggest that this treatment as a single agent is effective for mTNBC," Adams says. "Interestingly, we found that activity of pembrolizumab was seen in both PD-L1-positive and -negative tumors. These data are very encouraging, especially for a disease that is extremely aggressive and has limited treatment options when it metastasizes."

The goals of Cohort B, for which survival data are not yet complete, were, primarily, to prove pembrolizumab's safety and, secondarily, to explore its efficacy as a first-line treatment. Both goals appear to have been met.

"This research contributes to a larger body of knowledge that could help provide better outcomes to women with few treatment options," Adams adds. "The data also suggest that immunotherapy administered earlier in the disease course is more beneficial, as response rates are much greater in first- compared to second- or later lines of therapy."

Pembrolizumab, marketed under the name Keytruda, was well tolerated by both cohorts at a 200mg dose every three weeks, according to study results. Only 12 percent of patients in Cohort A experienced severe side effects and only eight percent experienced them in Cohort B. The most common side effects in both patient populations were fatigue and nausea. Although side effects led to discontinuation of treatment in seven patients from Cohort A, no patients in Cohort B discontinued treatment due to adverse side effects.

Triple negative breast cancer, which represents approximately 15 percent of all breast cancer diagnoses, is considered by many experts the most deadly form of the disease. Because it tests negatively for estrogen and progesterone receptors, it is unresponsive to hormonal therapies. Recurrence is common and often leads to metastases in other organs.

Currently, mTNBC is treated with chemotherapy, which is typically associated with significant toxicity and numerous side effects. Conversely, the side effects of pembrolizumab are much less frequent and more tolerable, says Adams.

Adams says more research is needed--such as identifying biomarkers, testing combination therapies and expanding clinical study to larger patient cohorts. Still, she is optimistic.

"Although only a small subset of women responded to the drug, within that subset pembrolizumab worked extremely well and responses were durable," Adams adds. "By causing fewer side effects and promoting longer life expectancy, pembrolizumab could help change the outcome of mTNBC."
-end-
Merck, the manufacturer of pembrolizumab, funded this clinical trial and provided Adams and her colleagues with research support.

NYU Langone Medical Center / New York University School of Medicine

Related Cancer Articles:

Radiotherapy for invasive breast cancer increases the risk of second primary lung cancer
East Asian female breast cancer patients receiving radiotherapy have a higher risk of developing second primary lung cancer.
Cancer genomics continued: Triple negative breast cancer and cancer immunotherapy
Continuing PLOS Medicine's special issue on cancer genomics, Christos Hatzis of Yale University, New Haven, Conn., USA and colleagues describe a new subtype of triple negative breast cancer that may be more amenable to treatment than other cases of this difficult-to-treat disease.
Metabolite that promotes cancer cell transformation and colorectal cancer spread identified
Osaka University researchers revealed that the metabolite D-2-hydroxyglurate (D-2HG) promotes epithelial-mesenchymal transition of colorectal cancer cells, leading them to develop features of lower adherence to neighboring cells, increased invasiveness, and greater likelihood of metastatic spread.
UH Cancer Center researcher finds new driver of an aggressive form of brain cancer
University of Hawai'i Cancer Center researchers have identified an essential driver of tumor cell invasion in glioblastoma, the most aggressive form of brain cancer that can occur at any age.
UH Cancer Center researchers develop algorithm to find precise cancer treatments
University of Hawai'i Cancer Center researchers developed a computational algorithm to analyze 'Big Data' obtained from tumor samples to better understand and treat cancer.
More Cancer News and Cancer Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Teaching For Better Humans
More than test scores or good grades — what do kids need to prepare them for the future? This hour, guest host Manoush Zomorodi and TED speakers explore how to help children grow into better humans, in and out of the classroom. Guests include educators Olympia Della Flora and Liz Kleinrock, psychologist Thomas Curran, and writer Jacqueline Woodson.
Now Playing: Science for the People

#534 Bacteria are Coming for Your OJ
What makes breakfast, breakfast? Well, according to every movie and TV show we've ever seen, a big glass of orange juice is basically required. But our morning grapefruit might be in danger. Why? Citrus greening, a bacteria carried by a bug, has infected 90% of the citrus groves in Florida. It's coming for your OJ. We'll talk with University of Maryland plant virologist Anne Simon about ways to stop the citrus killer, and with science writer and journalist Maryn McKenna about why throwing antibiotics at the problem is probably not the solution. Related links: A Review of the Citrus Greening...