Retrospective univariate biomarker analysis from a randomized phase 2 trial of the fully-human monoclonal, ligand competitive anti-ErbB3 agent seribantumab in combination with paclitaxel in patients with advanced platinum-resistant or refractory ovarian cancer suggested that patients with detectable levels of HRG had a progression-free survival hazard ratio that favored the experimental arm, whereas undetectable HRG favored the control arm9. Here, ERBB3 is linked to ovarian cancer.