Patritumab Deruxtecan — Investigational Agent
Antibody-Drug Conjugate · Phase 3 · Daiichi Sankyo / AstraZeneca
Mechanism of Action
Anti-HER3 antibody-drug conjugate (ADC). Composed of a fully human anti-HER3 (ErbB3) monoclonal antibody (patritumab) conjugated to a topoisomerase I inhibitor payload (DXd — the same payload as trastuzumab deruxtecan and datopotamab deruxtecan) via a tetrapeptide-based cleavable linker. Drug-to-antibody ratio (DAR) is approximately 8, enabling high payload delivery per binding event. HER3 is broadly expressed in NSCLC, breast, colorectal, and other solid tumors. Upon internalization, the linker is cleaved by intracellular lysosomal enzymes, releasing DXd within the tumor cell. The…
Investigational Indications
- EGFR-mutated (exon 19 deletion or L858R) non-small cell lung cancer (NSCLC) after progression on osimertinib and platinum-based chemotherapy
- Metastatic HR+/HER2-low breast cancer (post-CDK4/6 inhibitor and endocrine therapy)
- Other HER3-expressing solid tumors (colorectal, gastric, bladder, salivary gland — exploratory)