In part B, a total of 44 patients were assessed for eligibility (Supplementary Fig. 1a), and 20 patients with HR+/HER2- breast cancer and 17 patients with TNBC were enrolled in the study to receive a single dose of 5.6 mg/kg HER3-DXd (Fig. 1a). The gene discussed is ERBB3; the disease is breast cancer.