Oncothyreon, Array BioPharma Announce Initiation Of Phase 1b Trial Of ONT-380

(RTTNews) - Oncothyreon Inc. (ONTY) and Array BioPharma Inc. (ARRY) announced the initiation of a Phase 1b trial of ONT-380 or ARRY-380 in combination with Kadcyla (ado-trastuzumab emtansine or TDM-1) in patients with metastatic HER2+ breast cancer.

ONT-380 is an orally active, reversible and selective small-molecule HER2 inhibitor invented by Array and being developed by Oncothyreon in collaboration with Array.

The trial is a dose-escalation study in up to 48 patients who have been previously treated with Herceptin (trastuzumab) and a taxane for metastatic breast cancer. The primary objective is to determine the maximum-tolerated and/or recommended Phase 2 dose (MTD/RP2D) of ONT-380 in combination with the approved dose of Kadcyla.

Secondary objectives include an evaluation of the safety and preliminary anti-tumor activity of the combination. Following determination of the MTD/RP2D, the study includes an expansion arm at the MTD/RP2D as well as an optional second expansion arm in patients with central nervous system metastases.

"ONT-380 and Kadcyla are both directed at HER2, but with differing mechanisms of action.... "The strategy of combining two agents targeting HER2 has previously proven useful in HER2+ breast cancer, and we believe the combination of ONT-380 and Kadcyla is particularly relevant to evaluate as the treatment of metastatic HER2+ breast cancer continues to evolve," said Diana Hausman, M.D., Chief Medical Officer of Oncothyreon.