Phase III KATHERINE study of Kadcyla meets primary endpoint in HER2+ breast cancer.- Genentech/Roche.

Genentech/Roche announced the Phase III KATHERINE study met its primary endpoint, showing Kadcyla (ado-trastuzumab emtansine) as a single agent significantly reduced the risk of disease recurrence or death (invasive disease-free survival, iDFS) compared to Herceptin (trastuzumab) as an adjuvant (after surgery) treatment in people with HER2-positive early breast cancer (EBC) who have residual disease (pathological invasive residual disease in the breast and/or axillary nodes) present following neoadjuvant (before surgery) treatment. The safety profile of Kadcyla in the KATHERINE study was consistent with previous clinical trials and no new safety signals were identified.

The primary endpoint of the study is iDFS, which in this study is defined as the time from randomization to invasive breast cancer recurrence or death from any cause. Secondary endpoints include disease-free survival and overall survival. Full results will be submitted to health authorities around the world, and will be presented at the 2018 San Antonio Breast Cancer Symposium.

Comment: The KATHERINE trial investigated a population of people with HER2-positive EBC who did not achieve a pathological complete response to neoadjuvant treatment. This state of residual disease is associated with a worse prognosis.