New trial data from Roche shows that Perjeta, a new monoclonal antibody, significantly increases survival rates in patients with advanced HER2-positive breast cancer.

The Swiss pharmaceutical firm demonstrated at the San Antonio Breast Cancer Symposium that the risk of death was reduced by 34% in women treated with Perjeta and Herceptin plus chemotherapy, compared to patients treated with Herceptin and chemotherapy.

Data from the Phase III CLEOPATRA study shows that after one year of the trial, 94% of patients in the Perjeta arm were still alive, compared with 89% in the Herceptin group.

Dr. David Miles, consultant medical oncologist at the Mount Vernon Cancer Centre in the UK, said, "These results are really impressive, they show a rare magnitude of survival benefit for metastatic HER2-positive breast cancer patients."

"The strategy of using two HER2-targeted drugs with complementary mechanisms of action not only controls this aggressive disease, but also demonstrates that Perjeta will actually extend the lives of more patients while maintaining a quality of life comparable to Herceptin and chemotherapy in relation to the frequency of side effects."

Perjeta is the first in a new class of HER2 dimerisation inhibitors, which work to block cancer cell growth and survival signals.

By combining the drug with Herceptin, a more comprehensive blockade of HER2 is created, which leads to inhibited cell growth and cell death, said Roche.

Perjeta was granted approval by US health regulators in June. Roche is awaiting a decision from European regulators.

Image: Aerial view of Roche Basel from south with river Rhine, Switzerland. Image courtesy of Roche.