Petosemtamab — Investigational Agent
Bispecific Antibody · Phase 3 · Merus N.V.
Mechanism of Action
Biclonics IgG1 bispecific antibody targeting EGFR and LGR5. It blocks EGFR-driven signaling while binding LGR5 (a marker of cancer stem cells), positioning the antibody to promote EGFR internalization/degradation on LGR5+ tumor cells. The ADCC-enhanced (afucosylated) Fc recruits immune effector cells for antibody-dependent cellular cytotoxicity, adding an immune-mediated mechanism.
Investigational Indications
- Recurrent/metastatic head and neck squamous cell carcinoma (HNSCC)
- Metastatic colorectal cancer (earlier cohorts)