In a phase 1 trial, patients with locally advanced or metastatic EGFR-mutated NSCLC with prior EGFR TKI therapy (N = 57) were treated with HER3-DXd 5.6 mg/kg IV Q3W and the ORR was 39% (95% CI, 26.0–52.4%). The gene discussed is EGFR; the disease is non-small cell lung carcinoma.