Women with an aggressive type of breast cancer lived longer if they received immunotherapy plus chemotherapy, rather than chemo alone, a major study has found.
The results are expected to change the standard of care for women like those in the clinical trial, who had advanced cases of “triple-negative” breast cancer. That form of the disease often resists standard therapies, and survival rates are poor. It is twice as common in African-American women as in white women, and more likely to occur in younger women.
Researchers said the new study was a long-awaited breakthrough for immunotherapy in breast cancer. These findings may lead to the first approval by the U.S. Food and Drug Administration for an immunotherapy drug to treat breast cancer. But the approval would likely be limited to a certain type of aggressive cancer.
Although triple-negative tumours occur in only about 15% of patients with invasive breast cancer in the U.S. (or nearly 40,000 each year), they account for a disproportionate share of deaths, as many as 30 to 40%.
The term triple-negative refers to the tumours’ lack of sensitivity to the hormones estrogen and progesterone, and their lack of a protein called HER2, which is a target of treatment.
The immunotherapy in the study was atezolizumab (brand name Tecentriq), which belongs to a class of drugs called checkpoint inhibitors; the chemotherapy was nab-paclitaxel (Abraxane). The findings were published on Saturday in The New England Journal of Medicine , and were to be presented at a meeting of the European Society for Medical Oncology, in Munich.
The study included 902 patients treated at 246 medical centres in 41 countries. Genentech, which is part of Roche, has already submitted the data to the FDA for approval.
Treatment, side effects
Checkpoint inhibitors like atezolizumab work by helping T-cells — a type of white blood cell that is part of the immune system — recognize cancer and attack it. Research that led to these drugs won this year’s Nobel Prize in medicine.
The drugs generally work for fewer than half of patients, but can bring lasting recoveries even to people who were severely ill. Side effects can be dangerous, even life-threatening, and treatment costs over $100,000 a year.NY Times