Addition of pertuzumab to adjuvant regimen reduces recurrence risk in HER-2–positive breast cancer

The addition of pertuzumab to adjuvant trastuzumab and chemotherapy significantly extended invasive DFS among patients with HER-2–positive early breast cancer, according to phase 3 study results released by the agent’s manufacturer.

The international, double blind, placebo-controlled APHINITY study evaluated the safety and efficacy of adjuvant pertuzumab (Perjeta, Genentech) plus trastuzumab (Herceptin, Genentech) and chemotherapy compared with trastuzumab and chemotherapy alone.

The analysis included 4,805 people with operable HER-2–positive early-stage breast cancer.

Researchers randomly assigned half of the study participants to six to eight cycles of chemotherapy plus pertuzumab and trastuzumab, followed by pertuzumab and trastuzumab every 3 weeks for 1 year. The other half received six to eight cycles of chemotherapy plus placebo and trastuzumab, followed by placebo and trastuzumab every 3 weeks for 1 year.

The study met its primary endpoint, as the pertuzumab regimen conferred a statistically significant improvement in invasive DFS.

Secondary endpoints included cardiac and overall safety, OS, DFS and health-related quality of life. Complete data will be scheduled for presentation at a medical meeting later this year.

“These results from the positive APHINITY study represent an important addition to the body of data for pertuzumab in the treatment of people with HER-2–positive early breast cancer,” Sandra Horning, MD, chief medical officer and head of global product development at Genentech, said in a company-issued press release. “We look forward to discussing these adjuvant results with global regulatory authorities.”

The pertuzumab regimen exhibited a safety profile consistent with that observed in prior studies. Researchers identified no new safety signals.

“APHINITY provides yet another example of the importance of industry–academic collaborations and their value in advancing cancer care for people affected by this challenging disease,” study coordinator Gunter von Minckwitz, MD, of the Breast International Group, said in the press release.

The combination of pertuzumab, trastuzumab and docetaxel chemotherapy received accelerated approval for neoadjuvant treatment of patients with HER-2–positive, locally advanced, inflammatory or early stage breast cancer.