The US Food and Drug Administration has granted a priority review to the combination of Perjeta and Herceptin to treat HER2-positive early breast cancer (EBC) after surgery.

Roche subsidiary Genentech’s supplemental Biologics License Application (sBLA) for the use of Perjeta (pertuzumab), Herceptin (trastuzumab) and Perjeta-based chemotherapy is based on the Phase III APHINITY study.

The international, randomized, double-blind trial looks at the efficacy and safety of Perjeta plus Herceptin and chemotherapy compared to Herceptin and chemotherapy as adjuvant therapy in 4,805 people with operable HER2-positive EBC.

Perjeta targets the HER2 receptor, which is prevalent on the outside of cancer cells in HER2-positive cancers. Its action is believed to complement that of Perjeta, since both drugs bind to different places in the HER2 receptor.

This dual action is thought to block HER signalling pathways more strongly, thus preventing the growth and survival of tumour cells.

Priority review designation is given to medicines the FDA believes have the potential to provide significant improvements in the treatment, prevention or diagnosis of a disease. The regulator is expected to make a decision by the end of January.

“Despite advances in the treatment of this disease, many people treated with the current standard of care still see their cancer return,” said Sandra Horning, Roche’s chief medical officer and head of Global Product Development.

APHINITY’s primary efficacy endpoint is invasive disease-free survival (iDFS) – which is defined as the time a patient is able to live without return of invasive breast cancer or death from any cause after adjuvant treatment.

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

In the US, the combination of Perjeta, Herceptin and docetaxel chemotherapy is currently available under accelerated approval for neoadjuvant treatment of HER2-positive, locally advanced, inflammatory, or early stage breast cancer.

The drug is also approved for use in combination with Herceptin and docetaxel for metastatic HER2-positive breast cancer. But there is no evidence that Perjeta treatment prior to surgery improves survival, and its safety in combination with doxorubicin-containing regimens has not been established.