In BOLERO-3, the addition of everolimus to trastuzumab and vinorelbine significantly prolonged PFS compared to trastuzumab and vinorelbine alone in patients with HER2+ advanced breast cancer progressing on prior trastuzumab and taxane (median PFS 7.0 months vs 5.78 months; hazard ratio = 0.78 (95% CI 0.65–0.95)); P = 0.0067) [15]. Here, ERBB2 is linked to breast cancer.