Genentech’s trastuzumab emtansine (T-DM1) has yielded positive results in a randomised Phase III study conducted in patients with HER2-positive metastatic breast cancer (mBC) who had previously received treatment with Herceptin (trastuzumab) and a taxane chemotherapy.

Trastuzumab emtansine is an antibody drug conjugate (ADC) designed to inhibit HER2 signalling and deliver the chemotherapy agent DM1 directly inside HER2-positive cancer cells.

Emilia (TDM4370g/BO21977), an international Phase III randomised open-label study, enrolled 991 people with HER2-positive mBC to compare trastuzumab emtansine alone to lapatinib in combination with Xeloda.

In the trial, the co-primary efficacy endpoints were progression-free survival (PFS), overall survival (OS), safety profile, one-year and two-year survival rates, PFS as assessed by investigator, overall response rate, duration of response and quality of life.

The study showed people who received trastuzumab emtansine considerably extended the survival time without their disease getting worse compared to those who received lapatinib plus xeloda.

Genentech Global Product Development chief medical officer and head Hal Barron said trastuzumab emtansine represents a new approach for the treatment of people with HER2-positive breast cancer.

"We are excited about the EMILIA results because trastuzumab emtansine is our first antibody-drug conjugate and it may help people who still need more treatment options for this aggressive disease. We will work to submit these data to regulatory authorities as quickly as possible," Barron added.

Following the positive results, the company intends to submit a Biologics Licence Application for trastuzumab emtansine to the US Food and Drug Administration (FDA) this year for HER2-positive mBC.

In addition to Emilia, the two ongoing Phase III studies, Marianne and Th3resa, are comparing trastuzumab emtansine regimens and trastuzumab emtansine alone in people with HER2-positive mBC who have not been previously treated for their metastatic disease and who have already received both Herceptin and lapatinib respectively.


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