ERBB2 and neoplasm: However, unlike ADCs or bispecific Tcell engagers that deliver cytotoxic payloads or recruit immune effectors,eTPD efficacy depends on the biological importance of the target itself.Effective targets are typically those essential for tumor growth orsurvival, such as mutant epidermal growth factor receptor (EGFR) withconstitutive autophosphorylation or humanepidermal growth factor receptor 2 (HER2) amplification.