BASEL, Switzerland—The end of September has also heralded the final set of survival results from Roche’s CLEOPATRA study of Perjeta (pertuzumab) as a combination therapy for patients with breast cancer. The study demonstrated that combining Perjeta with Herceptin (trastuzumab) and docetaxel chemotherapy served to extend overall survival of patients with previously untreated HER2-positive metastatic breast cancer by 15.7 months compared to just Herceptin and chemotherapy (56.5 months vs. 40.8 months). Risk of death was reduced by 32 percent for patients receiving the Perjeta regimen compared to those who did not. The study saw a median progression-free survival of 18.7 months for people receiving the Perjeta combination, compared to 12.4 months for those being treated with just Herceptin and chemotherapy.
The CLEOPATRA study was an international, Phase 3, randomized, double-blind, placebo-controlled study. The trial sought to compare the Perjeta, Herceptin and docetaxel chemotherapy regimen with placebo, Herceptin and chemotherapy in 808 people with previously untreated HER2-positive metastatic breast cancer, or with HER2-positive metastatic breast cancer that had returned after prior therapy in the adjuvant or neoadjuvant setting. The study’s primary endpoint was progression-free survival, with secondary endpoints consisting of overall survival and safety profile.
Perjeta’s safety profile was consistent with results previously noted in the CLEOPATRA study, including the drug’s long-term cardiac safety, and no new safety signals were observed. The most common adverse events in the Perjeta arm of the trial were diarrhea, rash, mucosal inflammation, headache, upper respiratory tract infection, itching, low white blood cell count with fever, dry skin and muscle spasms.
“Adding Perjeta to treatment with Herceptin and chemotherapy resulted in the longest survival observed to date in a clinical study of people with HER2-positive metastatic breast cancer," said Sandra Horning, M.D., chief medical officer and head of Global Product Development at Roche. “The median survival of nearly five years for people who received the Perjeta regimen is 15.7 months longer than for people who received Herceptin and chemotherapy alone, a magnitude of improvement we rarely see in clinical trials in advanced cancer.”
Perjeta targets the HER2 receptor and is designed to prevent it from pairing with other HER receptors (EGFR/HER1, HER3 and HER4) on the surface of cells, which is thought to factor into tumor growth and survival. In addition, it is thought that binding Perjeta to HER2 may instruct the immune system to target and destroy the cancer cells. The benefit of Perjeta and Herceptin being administered together is that since the drugs bind to the HER2 receptor in different places, it offers a more comprehensive blocking of HER signaling pathways.
The therapeutic combination of Perjeta, Herceptin and docetaxel chemotherapy is approved in the United States and the European Union for people who have not received previous treatment for this cancer subtype. It has also received accelerated approval from the U.S. Food and Drug Administration as a neoadjuvant treatment (use before surgery) for HER2-positive early breast cancer, and approval is being sought to update its Marketing Authorization to include that indication in the European Union as well.
SOURCE: Roche press release
