Of the 722 patients in the study, the majority of patients had HER2-negative disease (90%), with a small number of patients with unknown (8%) or confirmed HER2-positive status (2%), who had previously been treated with or were considered unsuitable for trastuzumab therapy.
Jälkimmäiseen ryhmään kuuluvia potilaita oli aikaisemmin hoidettu trastutsumabilla tai trastutsumabihoito ei soveltunut heille.