Roche's T-DM1 shrinks tumors in Ph II study

Phase II study data presented at the American Society of Clinical Oncology meeting in Orlando, Florida, show that 25% of women with  advanced HER2-positive breast cancer experienced significant tumor  shrinkage with Swiss drug major Roche's antibody-drug conjugate  trastuzumab-DM1.

T-DM1 is made up of Roche's proven treatment Herceptin (trastuzumab), an  antibody that specifically targets HER2, and DM1, a chemotherapy agent.  Trastuzumab delivers DM1 to the tumor where it kills cells overproducing  HER2, which cause cancer. By combining both of these components, T-DM1  is able to specifically target cancer cells and maximize clinical  benefit while minimizing harmful side effects, Roche noted.

In the trial, 35% of patients either saw their tumors shrink, or their  disease stabilize for at least six months. When the HER2-status of  subjects was re-assessed in a central laboratory, the percentage of  patients who experienced such a clinical benefit rose to 44%.