Adding Pertuzumab to Trastuzumab and Chemotherapy in HER2-Positive Breast Cancer
Among patients with HER2-positive, operable breast cancer, adding pertuzumab to adjuvant trastuzumab and chemotherapy significantly improved the rates of invasive disease–free survival, according to the results of the APHINITY trial. Gunter von Minckwitz, MD, President of the German Breast Group in Neu-Isenburg, Germany, presented these findings at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract LBA500) and published them in The New England Journal of Medicine.
“These are very early results, but given the absolute benefit from adding pertuzumab was modest, we should consider using it primarily in women with the highest risk—those with node-positive and hormone receptor–negative breast cancer,” said Dr. von Minckwitz in a recent interview with The ASCO Post.
The trial population included 4805 patients, with approximately half receiving chemotherapy, trastuzumab, and pertuzumab (pertuzumab group) and the other half receiving chemotherapy, trastuzumab, and placebo (placebo group). Of these patients, 63% had node-positive disease, and 36% had hormone receptor–negative disease.
Disease recurred in more patients in the placebo group than in the pertuzumab group (8.7% vs. 7.1%; P=.045). In the pertuzumab group, the 3-year rate of invasive disease–free survival was estimated at 94.1%, compared with 93.2% in the placebo group. There also seemed to be a slight benefit with the addition of pertuzumab in the higher-risk group of those with node-positive disease, although that was not the case in those with node-negative disease.
Grade 3 or higher diarrhea occurred almost exclusively during chemotherapy, and it was more common with pertuzumab than with placebo (9.8% vs. 3.7%).