Huadong Medicine Co., Ltd. (000963.SZ) announced that on March 10, 2026, its wholly-owned subsidiary, Hangzhou Zhongmei Huadong Pharmaceutical Co., Ltd., received notification from the U.S. Food and Drug Administration (FDA) that the Investigational New Drug application for injectable HDM2024 has been approved. The clearance allows the initiation of a Phase I clinical trial in the United States for the treatment of advanced solid tumors. Injectable HDM2024 is a novel Class 1 biologic drug wholly developed by Zhongmei Huadong and owned globally by the company. It is a new bispecific antibody-drug conjugate (Bs-ADC) targeting both Epidermal Growth Factor Receptor 1 (EGFR/HER1) and Human Epidermal Receptor 3 (HER3). The drug candidate consists of a bispecific antibody targeting EGFR/HER3, a cleavable linker, and a DNA topoisomerase I inhibitor cytotoxic payload. HDM2024 simultaneously blocks the EGFR/HER3 signaling pathways, effectively inhibiting tumor cell proliferation signals while delivering a cytotoxic payload into tumor cells to exert anti-tumor effects. Preclinical studies have demonstrated that HDM2024 exhibits potent anti-tumor activity in various solid tumor models with different target expression levels, showing promising druggability and a favorable safety profile.