The human epidermal growth factor receptor 2 (HER2) is a
prominent target for tumor targeting since the malignant growth of
carcinomas from multiple tissues is linked to the overexpression
of this receptor tyrosine kinase.
Patients do already benefit from several anti-HER2 drugs like the
monoclonal antibodies trastuzumab (Herceptin®) and pertuzumab
(Perjeta®), which have been shown in vitro to act only as a
cytostatic agent, but not as a cytotoxic agent.
The mainly cytostatic mode of action might promote acquired
resistance towards the antibody treatment.
New HER2-binders employing alternative mechanisms to abolish
HER2-dependent signaling and causing cytotoxic effects could
expand and complement existing anti-HER2 therapies.