Genentech, a member of the Roche Group, has reported that its Phase III EMILIA study of trastuzumab emtansine in people with HER2-positive metastatic breast cancer (mBC) who had previously received Herceptin (trastuzumab) and taxane chemotherapy has met co-primary efficacy endpoints of overall survival and progression-free survival.

Trastuzumab emtansine (T-DM1), which is comprised of the antibody trastuzumab and the chemotherapy DM1, is designed to target and inhibit HER2 signalling and deliver DM1 directly inside HER2-positive cancer cells.

The randomised, open-label study showed that T-DM1 significantly extended the lives (improved overall survival) of people with HER2-positive mBC, compared to the combination of lapatinib and Xeloda (capecitabine).

Genentech global product development head and chief medical officer Dr Hal Barron said the people treated with trastuzumab emtansine survived significantly longer than those who received a standard option for this cancer.

"We believe that antibody-drug conjugates have the potential to change the future treatment of cancer, and we look forward to working with regulatory authorities in the hope of bringing another potential treatment option to people with HER2-positive metastatic breast cancer," Barron said.

On the basis of updated overall survival results, people in the lapatinib and Xeloda arm of the study will be offered the option to receive trastuzumab emtansine, according to the company.

Genentech has submitted a biologics licence application (BLA) for trastuzumab emtansine to the FDA, and Roche is expected to submit a marketing authorisation application to the European Medicines Agency.

While the company seeks regulatory approval, Genentech plans to open an Expanded Access Program (EAP) in the US to provide some HER2-positive mBC sufferers access to trastuzumab emtansine.

Photo: Building 32 at Genentech’s San Fransisco headquarters. The company’s Phase III cancer drug trial has met its co-primary endpoints. Image: Courtesy of Coolcaesar.