Treating triple negative breast cancer with immunotherapy alongside chemotherapy can substantially reduce recurrences, preliminary results suggest.
A trial of the combination demonstrated “promising anti-tumour activity” in women aged 22-80, according to lead author Professor Peter Schmid from Queen Mary University of London and St Bartholomew’s Hospital.
Triple negative breast cancer occurs in around 15% of cases – around 7,500 women in the UK each year.
Prof Schmid said: “Triple-negative breast cancer is a particularly aggressive form of cancer with the potential to devastate lives.
“We have been desperately looking for better treatment options. These early results suggest that the addition of immunotherapy to chemotherapy leads to a substantial reduction in recurrences in this form of breast cancer.
“These are preliminary results, but they are very promising. If we prevent the cancer from coming back, we cure more patients, but we need longer-term data to confirm this.”
The trial took place in 124 sites across 21 countries between March 2017 and September 2018.
Some 784 patients received the immunotherapy drug pembrolizumab, before and after surgery, to remove the cancer, while 390 were given a placebo.
Both groups received cycles of chemotherapy to shrink the tumour.
The cancer was more likely to have disappeared in the patients who had immunotherapy as well as the chemotherapy when they underwent surgery
Some 64.8% of those who received immunotherapy showed no signs of cancer in their tissue, compared to 51.2% of those treated with the chemotherapy plus placebo.
Prof Schmid told PA news agency: “We know if the cancer is completely gone out of the breast, they have a much better long-term survival, the cure rates are much higher.
“Whereas in patients where there is still cancer visible at the time that we do the operation, they have a higher risk of recurrence.”
Early results also show a “favourable trend” in those patients staying cancer-free over the follow up period, which Prof Schmid said was “incredibly encouraging”.
Future analysis will track recurrences of the cancer in both groups over a longer period of time.
The findings were presented at the ESMO 2019 Congress in Barcelona, Spain.