Promising international trial could add more treatment options for triple negative breast cancer
Promising results from an international clinical trial using the immunotherapy drug nivolumab may increase the number of treatment options available for people with early-stage triple negative breast cancer (TNBC).
With addition of nivolumab to their chemotherapy, over half of patients involved in the Neo-N trial had no evidence of residual invasive cancer at the time of their surgery.
Lisa Martin from Waikato was one of these women, and she shared her story with New Zealand Herald. Two years ago, she was diagnosed with triple negative breast cancer, and rapidly joined the Neo-N clinical trial.
Like many women with TNBC, she was due to have her chemo before surgery. Neo-N added nivolumab to her chemo and halved the number of chemotherapy cycles she went through. When Lisa had her surgery, there was no evidence of residual invasive cancer in her breast and in the nodes removed from her armpit.
Around 11% of the breast cancers in New Zealand are triple negative, meaning that these cancers have no expression of the two hormone receptors and the HER2 receptor. This type of breast cancer usually has an aggressive clinical behaviour and is more likely to recur early. It doesn't have as many treatment options as the other types, nearly always requiring chemotherapy, and often affects younger women, like Lisa.
Immunotherapy drugs, where Keytruda (pembrolizumab) is the most well-known, are used to cure early stage TNBC. Breast Cancer Foundation NZ is pushing for Pharmac to fund an immunotherapy drug for TNBC. Right now, patients with TNBC either have to fund immunotherapy drugs themselves or go without.
Neo-N wanted to see if the addition of immunotherapy to a shorter chemotherapy regimen prior to surgery could achieve a high rate of complete resolution of invasive TNBC in the breast and armpit nodes at surgery. It used a regimen that would be an option for more patients, including elderly patients and patients with heart and vascular conditions. The trial looked at whether using nivolumab with chemotherapy was safe and effective in treating early stage triple negative breast cancer (stage I-II) as well as if adding the drug could compensate for giving less chemotherapy.
Coordinated by the Australia New Zealand Breast Cancer Trials group, Neo-N involved 108 patients with early stage triple negative breast cancer, four of them from New Zealand.
Patients received chemotherapy and immunotherapy before their operation, with the goal being that this combination would give the same outcomes but with less short- and long-term side effects.
The results, recently presented as a late-breaking abstract at the San Antonio Breast Cancer Symposium in the United States, found that over half of the patients with triple negative breast cancer had no evidence of cancer in the breast and armpit nodes at surgery following prior chemo and immunotherapy treatment.
Study co-chair and Waikato medical oncologist Dr Marion Kuper, who is also a member of Breast Cancer Foundation’s Medical Advisory Committee, says, “This new treatment has shown to be very effective at eradicating the cancer in patients with early stage triple negative breast cancer. Patients who have no residual invasive cancer in the breast and the armpit nodes at the time of surgery have a good prognosis. The chemotherapy regimen used in the Neo-N trial could also be given to elderly patients and to people with other pre-existing illnesses that put them at risk of getting heart damage from the more toxic chemotherapy they might otherwise receive.”
More research needs to be done before nivolumab becomes the standard of care in treating early-stage TNBC, but the initial results are promising.
The Neo-N trial is going to be extended with a third treatment arm, which includes two different immunotherapy drugs combined with this shorter chemotherapy regimen.