Regarding cardiac toxicities associated with osimertinib, a previous investigation reported the incidence of cardiac failure (1.6%), arterial fibrillation (1.2%), QT prolongation (1.3%), and cardiac failure (0.7%).[5] Trastuzumab, a monoclonal antibody against human epidermal growth factor receptor 2 (HER2), has been linked to the occurrence of cardiotoxicity. The gene discussed is ERBB2; the disease is heart failure.