Breast Cancer Drug Combination Increases Disease-Free Survival

Adding pertuzumab (Perjeta) to a breast cancer treatment regimen reduced recurrent disease.

Roche recently announced positive results from the phase 3 APHINITY clinical trial, which showed a combination therapy increased invasive disease-free survival in patients with breast cancer.

The study accomplished its primary endpoint, and demonstrated that pertuzumab (Perjeta), trastuzumab (Herceptin), and chemotherapy (pertuzumab-based regimen) significantly reduced the risk of recurrent invasive disease or death, compared with trastuzumab and chemotherapy alone, according to a press release.

Secondary endpoints include cardiovascular safety, overall survival, disease-free survival, and health-related quality of life.

Included in the study were 4805 patients with operable HER2-positive early breast cancer who were randomized to receive adjuvant treatment with pertuzumab, trastuzumab, and chemotherapy or trastuzumab plus chemotherapy.

Patients either received 6 to 8 cycles of a chemotherapy regimen including pertuzumab and trastuzumab, followed by treatment with pertuzumab and trastuzumab every 3 weeks for 1 year; or 6 to 8 cycles of a chemotherapy regimen including placebo and trastuzumab, followed by treatment with placebo and trastuzumab every 3 weeks for 1 year.

After the end of adjuvant chemotherapy, patients were administered radiotherapy or endocrine therapy, Roche reported.

The addition of pertuzumab was seen to improve overall survival, with no new safety concerns arising. The safety profile of pertuzumab was observed to be in line with previous findings, according to the press release.

“These results from the positive APHINITY study represent an important addition to the body of data for Perjeta in the treatment of people with HER2-positive early breast cancer,” said Sandra Horning, MD, chief medical officer and head of Global Product Development at Roche. “We look forward to discussing these adjuvant results with global regulatory authorities.”

HER2-positive breast cancer is particularly aggressive, affecting 1 in 5 patients diagnosed with the disease. This subtype of breast cancer is associated with poor prognosis if untreated, according to Roche. Regardless of therapeutic advances, 1 in 3 patients treated with the trastuzumab-chemotherapy regimen will experience recurrent disease that can become advanced or metastasize.

Additional treatment options are needed to improve outcomes, and focusing on early stage disease could reduce the risk of recurrent disease and mortality, according to Roche.

Currently, the combination of pertuzumab, trastuzumab, and chemotherapy is indicated as a neoadjuvant treatment for patients in more than 75 countries, and is believed to provide a more comprehensive inhibition of HER signaling pathways, according to the release. In the United States, the combination treatment was granted fast track designation.

Roche plans to present these data to regulatory authorities, including the FDA, to receive full approval for the treatment.

“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,” said study coordinator from the Breast International Group Gunter von Minckwitz, MD.