HealthDay News — Women with advanced, triple-negative breast cancers who responded to the immunotherapy atezolizumab (Tecentriq) gained a significant survival benefit, according to a study presented at the annual meeting of the American Association for Cancer Research, held from April 1 to 5 in Washington, D.C.
The trial included 112 patients who were treated with atezolizumab, an anti-PD-L1 immunotherapy. Nineteen of the 112 study participants got atezolizumab as their first line of therapy; the other 93 had already received at least two lines of prior treatment.
Overall, the response rate to the drug was low – just 11 of 112 patients. However, results were significant for the minority of patients who did respond, Peter Schmid, MD, PhD, director of the Breast Centre at St. Bartholomew’s Hospital and Barts Cancer Institute in London, said in a news release from the American Association for Cancer Research. “The most significant finding is the difference in the overall survival between patients who responded to atezolizumab and patients who did not respond,” he said. “While all responders were alive after one year, the one-year survival rate for nonresponders was only 38 percent.”
“Another noteworthy finding is that metastatic triple-negative breast cancer patients treated with atezolizumab had a prolonged median duration of response of 21 months, which is substantially longer than what has been seen with any other treatment to date for this patient population,” Schmid added. Side effects were relatively low. According to the researchers, 11% of patients had serious side effects, and only 3% of the women stopped using atezolizumab due to side effects.
The study was funded by Genentech, the manufacturer of atezolizumab.