Disappointing Phase III data for Kadcyla in Breast Cancer-Genentech/Roche

Genentech/Roche announced top-line results of the Phase III MARIANNE study evaluating three HER2-targeted regimens – Kadcyla (ado-trastuzumab emtansine) plus Perjeta (pertuzumab), Kadcyla alone, and Herceptin (trastuzumab) plus taxane chemotherapy – in people with previously untreated (first-line) advanced HER2-positive Breast Cancer. The study showed the three regimens helped people live without their disease worsening (PFS) for a similar amount of time, meeting its non-inferiority endpoint as assessed by an Independent Review Committee. However, neither Kadcyla-containing treatment arm significantly improved PFS compared to Herceptin plus chemotherapy. Adverse events observed in the two experimental arms of the study were generally consistent with those seen in previous studies of Kadcyla and/or Perjeta. Data from the MARIANNE study will be presented at an upcoming medical meeting. Roche and Genentech will discuss the data with health authorities.