Perjeta Regimen Improves Survival in HER2+ Early-Stage Breast Cancer

Treatment with Perjeta (pertuzumab), Herceptin (trastuzumab) and chemotherapy (Perjeta-based regimen) for one year as post-surgery treatment showed a statistically significant overall survival (OS) results in patients with HER2-positive early-stage breast cancer.

These results came from the phase 3 APHINITY study and were shared in a news release from Genentech.

“Early treatment of breast cancer can provide substantial patient benefit and also increases the chance for cure. For people with early-stage HER2-positive disease, the APHINITY results validate the sustained benefits of the Perjeta-based regimen,” Dr. Levi Garraway, Genentech’s chief medical officer and head of Global Product Development, said in the news release. “These long-term data reinforce the regimen’s value as a well-established standard-of-care treatment in the curative setting.”

Ten-year findings showed that 91.6% of patients who received the Perjeta-based regimen were still alive, compared with 89.8% of those who were treated with Herceptin, chemotherapy and placebo. Among individuals with lymph node-positive disease, there was a 21% drop in the risk of death. The benefit in invasive disease-free survival held steady over time, reinforcing earlier results from the APHINITY study. However, no similar benefit was observed in people without node involvement.

The treatment’s safety, including heart-related effects, matched what had been reported in earlier research, with no new concerns identified. According to safety information from the release, Perjeta can cause serious side effects, including heart problems, infusion-related reactions and severe allergic reactions. Common side effects include diarrhea, nausea, fatigue, hair loss, nerve damage and vomiting.

Full results will be shared in a late-breaking abstract on Thursday, May 15, at the 2025 European Society for Medical Oncology Breast Cancer Congress.

“After ten years, the APHINITY trial clearly shows a statistically significant and clinically meaningful improvement of the overall survival,” Professor Sibylle Loibl, APHINITY study chair, chair of the German Breast Group (GBG) and the chief executive officer of the GBG Forschungs GmbH, said in the news release. “Adding Perjeta to a standard adjuvant treatment is most beneficial for people with HER2-positive breast cancer with lymph node-positive disease who are at high risk of recurrence.”

The APHINITY study (Adjuvant Pertuzumab and Herceptin IN Initial TherapY in Breast Cancer) is a global phase 3 trial that enrolled 4,804 people with operable HER2-positive early-stage breast cancer. The randomized, double-blind study compared the use of Perjeta plus Herceptin and chemotherapy versus Herceptin and chemotherapy alone as adjuvant treatment, given after surgery.

The primary goal was to measure invasive disease-free survival, or the length of time a person lived without the return or spread of invasive breast cancer or death from any cause. Secondary goals included monitoring heart-related and overall safety, overall survival, and health-related quality of life.

“The international collaborations in APHINITY have facilitated important insights about HER2-positive breast cancer and are continuing to yield promising findings,” Liz Frank, independent research advocate, said in the news release. “Scientists and clinicians are working together with the broader goal of improving our understanding of HER2-positive breast cancer, improving the quality of life for people living with the disease and ultimately, helping them to live longer with no disease occurring.”

Perjeta is a prescription medication approved for use with Herceptin and chemotherapy to treat HER2-positive breast cancer. It is used both before surgery (neoadjuvant) for early-stage breast cancer and after surgery (adjuvant) for cases at high risk of recurrence. It is also approved for use with Herceptin and docetaxel in treating metastatic HER2-positive breast cancer in patients who have not received prior anti-HER2 therapy or chemotherapy.

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