Pertuzumab Plus Standard Treatment in HER2-Positive Early Breast Cancer
Posted: Tuesday, January 14, 2020
Data from a 6-year analysis of the phase III APHINITY trial, presented at the 2019 San Antonio Breast Cancer Symposium (SABCS; Abstract GS1-04), demonstrated that adding pertuzumab to trastuzumab plus chemotherapy continued to lower the odds of disease recurrence and death in patients with HER2-positive early breast cancer. Martine Piccart, MD, PhD, of Institut Jules Bordet, Brussels, and colleagues found that fewer deaths occurred in patients treated with pertuzumab, although a survival benefit was not deemed statistically significant.
“The evidence is now even stronger than adding pertuzumab to the previous standard of care reduces the risk of disease recurrence for patients with HER2-positive breast cancer,” Dr. Piccart said in an American Association for Cancer Research press release. “A longer follow-up is needed to see any significant survival benefit.”
In this trial, the investigators randomly assigned patients with operable HER2-positive early breast cancer to receive standard adjuvant chemotherapy plus trastuzumab with the addition of pertuzumab (2,400 patients) or a placebo (2,405 patients).
The investigators observed fewer deaths for those treated with pertuzumab than with a placebo (125 vs. 147 deaths, respectively). The 6-year overall survival for patients treated with pertuzumab was 94.8%, compared with 93.9% for those in the placebo group. An updated analysis measuring invasive disease–free survival from 508 events in the intent-to-treat population revealed that patients taking pertuzumab had a 6-year invasive disease–free survival of 90.6%, compared with 87.8% for those in the placebo arm.
Patients in the node-positive population continued to “derive clear benefit” from the addition of pertuzumab. With longer treatment, the authors also noted a treatment benefit for those with hormone receptor–positive disease. An additional primary cardiac event (heart failure) was reported in the pertuzumab arm of the trial, and one additional patient in both groups experienced a secondary cardiac event.
Disclosure: For full disclosures of the study authors, visit abstractsonline.com.