ES104 is a bispecific antibody that simultaneously blocks Delta-like ligand 4/Notch (DLL4) and vascular endothelial growth factor A (VEGF-A) signaling pathways, which are critical to angiogenesis and tumor vascularization. Pre-clinical and early clinical data of ES104 show that blocking both pathways provides robust anti-tumor activity across several solid tumors, including colorectal, gastric, cholangiocarcinoma, pancreatic, and non-small cell lung cancer. Partial responses to ES104 as monotherapy have been observed in heavily pre-treated cancer patients, who were resistant to currently approved anti-VEGF therapies.


A Phase 1 monotherapy dose-escalation and expansion study for ES104 was completed in South Korea, and a Phase 1b and Phase 2 combination studies are ongoing. In October 2021 Center of Drug Evaluation (CDE) cleared Elpiscience’s IND application for ES104 to initiate a Phase 1 clinical trial in China. Greater China Rights for ES104 are held by Elpiscience.