ERBB2 and breast cancer: This randomised, double-blind study compared pharmacokinetics, efficacy, safety and immunogenicity of PF-05280014 (potential trastuzumab biosimilar) and trastuzumab reference product (Herceptin) sourced from the European Union (trastuzumab-EU) as neoadjuvant treatment for operable human epidermal growth factor receptor 2 (HER2)-positive breast cancer.