Trastuzumab-DM1 (T-DM1) consists of our DM1 cell-killing agent attached to the HER2-binding antibody, trastuzumab, developed by Genentech (a wholly owned member of the Roche Group).

T-DM1 is in global development by Genentech and Roche for the treatment of HER2+ metastatic breast cancer (MBC). Additionally, Genentech has disclosed that trials to evaluate T-DM1 for early stage HER2+ breast cancer (adjuvant use) are being considered.

Development for 3rd-line Treatment of HER2+ MBC

Positive clinical data were reported from the Phase II evaluating T-DM1 for 3rd-line* treatment of HER2+ MBC at the San Antonio Breast Cancer Symposium in December 2009, and Genentech noted its plans to discuss next steps with the FDA. This is consistent with previous statements made by Genentech, which had said that if the findings from this trial were compelling, it would discuss an earlier approval pathway with the FDA.

Additional data from this study are expected to be presented at an upcoming medical meeting.

Development for 2nd-line Treatment of HER2+ MBC

Patient enrollment is reported to be on track in the Phase III trial (EMILIA) evaluating T-DM1 for 2nd-line** use. This 580-patient randomized trial began in February 2009 and compares T-DM1 – used as a single agent – to Tykerbâ (lapatinib) plus Xelodaâ (capecitabine).

Development for 1st-line Treatment of HER2+ MBC

Patient enrollment has completed in a Phase II trial evaluating T-DM1 for this use, and interim data from this trial are expected to be submitted for presentation at a medical meeting in 2010. This trial compares T-DM1, given as a single agent, to Herceptinâ (trastuzumab) plus Taxotereâ (docetaxel).

A Phase III 1st-line trial is targeted to begin in mid-2010.

Information on these and other T-DM1 clinical trials can be found at ClinicalTrials.gov.

*Patients must have had prior treatment with at least two lines of anti-HER2 therapy in the metastatic setting, and must have received an anthracycline, a taxane, trastuzumab, lapatinib and capecitabine in the neoadjuvant, adjuvant, locally advanced or metastatic setting.
**Patients must have received prior treatment that included both a taxane (alone or in combination with another agent) and trastuzumab in the adjuvant, locally advanced or metastatic setting.

Tykerbâ is a registered trademark of GlaxoSmithKline plc.
Xelodaâ is a registered trademark of Roche.
Herceptinâ is a registered trademark of Genentech, a wholly owned member of the Roche Group.
Taxotereâ is a registered trademark of sanofi-aventis.